Merge branch 'main' into vb/update-get-state

2026-09-07 10:17:50 +02:00 · 2024-08-12 10:26:56 -04:00
parent a7d48465da 4e643baaa6
commit c9d6a41d75
186 changed files with 25683 additions and 15750 deletions
@@ -36,7 +36,10 @@
            working-directory: [
                "libs/langgraph",
                "libs/sdk-py",
-                "libs/cli"
+                "libs/cli",
+                "libs/checkpoint",
+                "libs/checkpoint-sqlite",
+                "libs/checkpoint-postgres"
            ]
        uses: ./.github/workflows/_lint.yml
        with:
@@ -50,7 +53,10 @@
          matrix:
            working-directory: [
                "libs/langgraph",
-                "libs/cli"
+                "libs/cli",
+                "libs/checkpoint",
+                "libs/checkpoint-sqlite",
+                "libs/checkpoint-postgres"
            ]
        uses: ./.github/workflows/_test.yml
        with:
@@ -6,7 +6,7 @@ on:
      working-directory:
        required: true
        type: string
-        default: 'libs/langgraph'
+        default: "libs/langgraph"

 env:
  PYTHON_VERSION: "3.11"
@@ -104,7 +104,7 @@ jobs:
            REGEX="^$SHORT_PKG_NAME==\\d+\\.\\d+\\.\\d+((a|b|rc)\\d+)?\$"
          fi
          echo $REGEX
-          PREV_TAG=$(git tag --sort=-creatordate | grep -P $REGEX | head -1)
+          PREV_TAG=$(git tag --sort=-creatordate | grep -P $REGEX | head -1 || echo "")
          echo $PREV_TAG
          if [ "$TAG" == "$PREV_TAG" ]; then
            echo "No new version to release"
@@ -137,8 +137,7 @@ jobs:
      - build
      - release-notes
    permissions: write-all
-    uses:
-      ./.github/workflows/_test_release.yml
+    uses: ./.github/workflows/_test_release.yml
    with:
      working-directory: ${{ inputs.working-directory }}
    secrets: inherit
@@ -198,9 +197,15 @@ jobs:
              "$PKG_NAME==$VERSION" \
          )

-          # Replace all dashes in the package name with underscores,
-          # since that's how Python imports packages with dashes in the name.
-          IMPORT_NAME="$(echo "$PKG_NAME" | sed s/-/_/g)"
+          if [[ "$PKG_NAME" == *checkpoint* ]]; then
+            # since checkpoint packages are namespace packages, import them with . convention
+            # i.e. import langgraph.checkpoint or langgraph.checkpoint.sqlite
+            IMPORT_NAME="$(echo "$PKG_NAME" | sed s/-/./g)"
+          else
+            # Replace all dashes in the package name with underscores,
+            # since that's how Python imports packages with dashes in the name.
+            IMPORT_NAME="$(echo "$PKG_NAME" | sed s/-/_/g)"
+          fi

          poetry run python -c "import $IMPORT_NAME; print(dir($IMPORT_NAME))"

@@ -0,0 +1,28 @@
+name: Check File Size
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+  workflow_dispatch:
+
+jobs:
+  file-size-check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Get changed files
+        id: changed-files
+        uses: tj-actions/changed-files@v44
+      - name: Filter by size
+        run: |
+          large_added_files=$(find ${{ steps.changed-files.outputs.added_files }} -maxdepth 0 -size +1M)
+          if [ -n "$large_added_files" ]; then
+            echo "Large files added: $large_added_files"
+            echo "# Large files added:" >> $GITHUB_STEP_SUMMARY
+            echo "$large_added_files" >> $GITHUB_STEP_SUMMARY
+            exit 1
+          fi
@@ -3,7 +3,6 @@
 ![Version](https://img.shields.io/pypi/v/langgraph)
 [![Downloads](https://static.pepy.tech/badge/langgraph/month)](https://pepy.tech/project/langgraph)
 [![Open Issues](https://img.shields.io/github/issues-raw/langchain-ai/langgraph)](https://github.com/langchain-ai/langgraph/issues)
-[![](https://dcbadge.vercel.app/api/server/6adMQxSpJS?compact=true&style=flat)](https://discord.com/channels/1038097195422978059/1170024642245832774)
 [![Docs](https://img.shields.io/badge/docs-latest-blue)](https://langchain-ai.github.io/langgraph/)

 ⚡ Building language agents as graphs ⚡
@@ -11,9 +10,6 @@
 > [!NOTE]
 > Looking for the JS version? Click [here](https://github.com/langchain-ai/langgraphjs) ([JS docs](https://langchain-ai.github.io/langgraphjs/)).

-> [!TIP]
-> Looking to deploy your LangGraph application? [Join the waitlist](https://www.langchain.com/langgraph-cloud-beta) for [LangGraph Cloud](https://langchain-ai.github.io/langgraph/cloud/), our managed service for deploying and hosting LangGraph applications.
-
 ## Overview

 [LangGraph](https://langchain-ai.github.io/langgraph/) is a library for building stateful, multi-actor applications with LLMs, used to create agent and multi-agent workflows. Compared to other LLM frameworks, it offers these core benefits: cycles, controllability, and persistence. LangGraph allows you to define flows that involve cycles, essential for most agentic architectures, differentiating it from DAG-based solutions. As a very low-level framework, it provides fine-grained control over both the flow and state of your application, crucial for creating reliable agents. Additionally, LangGraph includes built-in persistence, enabling advanced human-in-the-loop and memory features.
@@ -62,7 +58,7 @@ from typing import Annotated, Literal, TypedDict
 from langchain_core.messages import HumanMessage
 from langchain_anthropic import ChatAnthropic
 from langchain_core.tools import tool
-from langgraph.checkpoint import MemorySaver
+from langgraph.checkpoint.memory import MemorySaver
 from langgraph.graph import END, StateGraph, MessagesState
 from langgraph.prebuilt import ToolNode

@@ -43,6 +43,7 @@ _MANUAL = {
        "tool-calling.ipynb",
        "tool-calling-errors.ipynb",
        "pass-config-to-tools.ipynb",
+        "many-tools.ipynb",
        "dynamic-returning-direct.ipynb",
        "managing-agent-steps.ipynb",
        "respond-in-format.ipynb",
@@ -58,6 +59,7 @@ _MANUAL = {
        "human_in_the_loop/time-travel.ipynb",
        "human_in_the_loop/edit-graph-state.ipynb",
        "human_in_the_loop/wait-user-input.ipynb",
+        "human_in_the_loop/review-tool-calls.ipynb",
        "node-retries.ipynb",
    ],
    "tutorials": [
@@ -12,6 +12,10 @@ An assistant is a configured instance of a [`CompiledGraph`][compiledgraph]. It

 The LangGraph Cloud API provides several endpoints for creating and managing assistants. See the <a href="../reference/api/api_ref.html#tag/assistantscreate" target="_blank">API reference</a> for more details.

+#### Configuring Assistants
+
+You can save custom assistants from the same graph to set different default prompts, models, and other configurations without changing a line of code in your graph. This allows you the ability to quickly test out different configurations without having to rewrite your graph every time, and also give users the flexibility to select different configurations when using your LangGraph application. See <a href="https://langchain-ai.github.io/langgraph/cloud/how-tos/cloud_examples/configuration_cloud/">this</a> how-to for information on how to configure a deployed graph. 
+
 ### Threads

 A thread contains the accumulated state of a group of runs. If a run is executed on a thread, then the [state][state] of the underlying graph of the assistant will be persisted to the thread. A thread's current and historical state can be retrieved. To persist state, a thread must be created prior to executing a run.
@@ -0,0 +1,146 @@
+# Rebuild Graph at Runtime
+
+You might need to rebuild your graph with a different configuration for a new run. For example, you might need to use a different graph state or graph structure depending on the config. This guide shows how you can do this.
+
+!!! note "Note"
+    In most cases, customizing behavior based on the config should be handled by a single graph where each node can read a config and change its behavior based on it
+
+## Prerequisites
+
+Make sure to check out [this how-to guide](./setup.md) on setting up your app for deployment first.
+
+## Define graphs
+
+Let's say you have an app with a simple graph that calls an LLM and returns the response to the user. The app file directory looks like the following:
+
+```
+my-app/
+|-- requirements.txt
+|-- .env
+|-- openai_agent.py     # code for your graph
+```
+
+where the graph is defined in `openai_agent.py`. 
+
+### No rebuild
+
+In the standard LangGraph API configuration, the server uses the compiled graph instance that's defined at the top level of `openai_agent.py`, which looks like the following:
+
+```python
+from langchain_openai import ChatOpenAI
+from langgraph.graph import END, MessageGraph
+
+model = ChatOpenAI(temperature=0)
+
+graph_workflow = MessageGraph()
+
+graph_workflow.add_node("agent", model)
+graph_workflow.add_edge("agent", END)
+graph_workflow.set_entry_point("agent")
+
+agent = graph_workflow.compile()
+```
+
+To make the server aware of your graph, you need to specify a path to the variable that contains the `CompiledStateGraph` instance in your LangGraph API configuration (`langgraph.json`), e.g.:
+
+```
+{
+    "dependencies": ["."],
+    "graphs": {
+        "openai_agent": "./openai_agent.py:agent",
+    },
+    "env": "./.env"
+}
+```
+
+### Rebuild
+
+To make your graph rebuild on each new run with custom configuration, you need to rewrite `openai_agent.py` to instead provide a _function_ that takes a config and returns a graph (or compiled graph) instance. Let's say we want to return our existing graph for user ID '1', and a tool-calling agent for other users. We can modify `openai_agent.py` as follows:
+
+```python
+from typing import Annotated, TypedDict
+from langchain_openai import ChatOpenAI
+from langgraph.graph import END, MessageGraph
+from langgraph.graph.state import StateGraph
+from langgraph.graph.message import add_messages
+from langgraph.prebuilt import ToolNode
+from langchain_core.tools import tool
+from langchain_core.messages import BaseMessage
+from langchain_core.runnables import RunnableConfig
+
+
+class State(TypedDict):
+    messages: Annotated[list[BaseMessage], add_messages]
+
+
+model = ChatOpenAI(temperature=0)
+
+def make_default_graph():
+    """Make a simple LLM agent"""
+    graph_workflow = StateGraph(State)
+    def call_model(state):
+        return {"messages": [model.invoke(state["messages"])]}
+
+    graph_workflow.add_node("agent", call_model)
+    graph_workflow.add_edge("agent", END)
+    graph_workflow.set_entry_point("agent")
+
+    agent = graph_workflow.compile()
+    return agent
+
+
+def make_alternative_graph():
+    """Make a tool-calling agent"""
+
+    @tool
+    def add(a: float, b: float):
+        """Adds two numbers."""
+        return a + b
+
+    tool_node = ToolNode([add])
+    model_with_tools = model.bind_tools([add])
+    def call_model(state):
+        return {"messages": [model_with_tools.invoke(state["messages"])]}
+
+    def should_continue(state: State):
+        if state["messages"][-1].tool_calls:
+            return "tools"
+        else:
+            return END
+
+    graph_workflow = StateGraph(State)
+
+    graph_workflow.add_node("agent", call_model)
+    graph_workflow.add_node("tools", tool_node)
+    graph_workflow.add_edge("tools", "agent")
+    graph_workflow.set_entry_point("agent")
+    graph_workflow.add_conditional_edges("agent", should_continue)
+
+    agent = graph_workflow.compile()
+    return agent
+
+
+# this is the graph making function that will decide which graph to
+# build based on the provided config
+def make_graph(config: RunnableConfig):
+    user_id = config.get("configurable", {}).get("user_id")
+    # route to different graph state / structure based on the user ID
+    if user_id == "1":
+        return make_default_graph()
+    else:
+        return make_alternative_graph()
+```
+
+Finally, you need to specify the path to your graph-making function (`make_graph`) in `langgraph.json`:
+
+```
+{
+    "dependencies": ["."],
+    "graphs": {
+        "openai_agent": "./openai_agent.py:make_graph",
+    },
+    "env": "./.env"
+}
+```
+
+See more info on LangGraph API configuration file [here](../reference/cli.md#configuration-file)
@@ -1,16 +1,31 @@
 # How to Set Up a LangGraph Application for Deployment

-A LangGraph application must be configured with a [LangGraph API configuration file](../reference/cli.md#configuration-file) in order to be deployed to LangGraph Cloud (or to be self-hosted). This how-to guide discusses the basic steps to setup a LangGraph application for deployment using `requirements.txt` to specify project dependencies. If you prefer using poetry for dependency management, check out [this how-to guide](./setup_pyproject.md) on using `pyproject.toml` for LangGraph Cloud.
+A LangGraph application must be configured with a [LangGraph API configuration file](../reference/cli.md#configuration-file) in order to be deployed to LangGraph Cloud (or to be self-hosted). This how-to guide discusses the basic steps to setup a LangGraph application for deployment using `requirements.txt` to specify project dependencies. 
+
+This walkthrough is based on [this repository](https://github.com/langchain-ai/langgraph-example), which you can play around with to learn more about how to setup your LangGraph application for deployment.
+
+!!! tip "Setup with pyproject.toml"
+    If you prefer using poetry for dependency management, check out [this how-to guide](./setup_pyproject.md) on using `pyproject.toml` for LangGraph Cloud.
+
+!!! tip "Setup with a Monorepo"
+    If you are interested in deploying a graph located inside a monorepo, take a look at [this](https://github.com/langchain-ai/langgraph-example-monorepo) repository for an example of how to do so.
+

 The final repo structure will look something like this:

 ```bash
 my-app/
-|-- requirements.txt    # package dependencies
-|-- .env                # environment variables
-|-- openai_agent.py     # code for an agent
-|-- anthropic_agent.py  # code for another agent
-|-- langgraph.json      # configuration file for LangGraph
+├── my_agent # all project code lies within here
+│   ├── utils # utilities for your graph
+│   │   ├── __init__.py
+│   │   ├── tools.py # tools for your graph
+│   │   ├── nodes.py # node functions for you graph
+│   │   └── state.py # state definition of your graph
+│   ├── requirements.txt # package dependencies
+│   ├── __init__.py
+│   └── agent.py # code for constructing your graph
+├── .env # environment variables
+└── langgraph.json # configuration file for LangGraph
 ```

 After each step, an example file directory is provided to demonstrate how code can be organized.
@@ -21,13 +36,11 @@ Dependencies can optionally be specified in one of the following files: `pyproje

 The dependencies below will be included in the image, you can also use them in your code, as long as with a compatible version range:
 ```
-langgraph>=0.1.7
-langchain-core>=0.2.7
-orjson>=3.10.1
-langsmith>=0.1.50
-httpx>=0.27.0
-langchain-core>=0.2.8
+langgraph>=0.2.0,<0.3.0
+langchain-core>=0.2.27,<0.3.0
 langsmith>=0.1.63
+orjson>=3.10.1
+httpx>=0.27.0
 tenacity>=8.3.0
 uvicorn>=0.29.0
 sse-starlette>=2.1.0
@@ -35,18 +48,24 @@ uvloop>=0.19.0
 httptools>=0.6.1
 jsonschema-rs>=0.18.0
 croniter>=1.0.1
+structlog>=24.4.0
 ```

 Example `requirements.txt` file:
 ```
 langgraph
+langchain_anthropic
+tavily-python
+langchain_community
 langchain_openai
+
 ```

 Example file directory:
-```
+```bash
 my-app/
-|-- requirements.txt    # Python packages required for your graph
+├── my_agent # all project code lies within here
+│   └── requirements.txt # package dependencies
 ```

 ## Specify Environment Variables
@@ -61,42 +80,66 @@ OPENAI_API_KEY=key
 ```

 Example file directory:
-```
+
+```bash
 my-app/
-|-- requirements.txt
-|-- .env                # file with environment variables
+├── my_agent # all project code lies within here
+│   └── requirements.txt # package dependencies
+└── .env # environment variables
 ```

 ## Define Graphs

 Implement your graphs! Graphs can be defined in a single file or multiple files. Make note of the variable names of each [CompiledGraph][compiledgraph] to be included in the LangGraph application. The variable names will be used later when creating the [LangGraph API configuration file](../reference/cli.md#configuration-file).

-Example `openai_agent.py` file:
+Example `agent.py` file, which shows how to import from other modules you define (code for the modules is not shown here, please see [this repo](https://github.com/langchain-ai/langgraph-example) to see their implementation):
+
+
 ```python
-from langchain_openai import ChatOpenAI
-from langgraph.graph import END, MessageGraph
+# my_agent/agent.py
+from typing import TypedDict, Literal

-model = ChatOpenAI(temperature=0)
+from langgraph.graph import StateGraph, END
+from my_agent.utils.nodes import call_model, should_continue, tool_node # import nodes
+from my_agent.utils.state import AgentState # import state

-graph_workflow = MessageGraph()
+# Define the config
+class GraphConfig(TypedDict):
+    model_name: Literal["anthropic", "openai"]

-graph_workflow.add_node("agent", model)
-graph_workflow.add_edge("agent", END)
-graph_workflow.set_entry_point("agent")
+workflow = StateGraph(AgentState, config_schema=GraphConfig)
+workflow.add_node("agent", call_model)
+workflow.add_node("action", tool_node)
+workflow.set_entry_point("agent")
+workflow.add_conditional_edges(
+    "agent",
+    should_continue,
+    {
+        "continue": "action",
+        "end": END,
+    },
+)
+workflow.add_edge("action", "agent")

-agent = graph_workflow.compile()
+graph = workflow.compile()
 ```

 !!! warning "Assign `CompiledGraph` to Variable"
-    The build process for LangGraph Cloud requires that the `CompiledGraph` object be assigned to a variable at the top-level of a Python module.
+    The build process for LangGraph Cloud requires that the `CompiledGraph` object be assigned to a variable at the top-level of a Python module (alternatively, you can provide [a function that creates a graph](./graph_rebuild.md)).

 Example file directory:
-```
+```bash
 my-app/
-|-- requirements.txt
-|-- .env
-|-- openai_agent.py     # code for your graph
-|-- anthropic_agent.py  # code for your graph
+├── my_agent # all project code lies within here
+│   ├── utils # utilities for your graph
+│   │   ├── __init__.py
+│   │   ├── tools.py # tools for your graph
+│   │   ├── nodes.py # node functions for you graph
+│   │   └── state.py # state definition of your graph
+│   ├── requirements.txt # package dependencies
+│   ├── __init__.py
+│   └── agent.py # code for constructing your graph
+└── .env # environment variables
 ```

 ## Create LangGraph API Config
@@ -106,14 +149,11 @@ Create a [LangGraph API configuration file](../reference/cli.md#configuration-fi
 Example `langgraph.json` file:
 ```json
 {
-    "dependencies": [
-        "."
-    ],
-    "graphs": {
-        "openai_agent": "./openai_agent.py:agent",
-        "anthropic_agent": "./anthropic_agent.py:agent"
-    },
-    "env": "./.env"
+  "dependencies": ["./my_agent"],
+  "graphs": {
+    "agent": "./my_agent/agent.py:graph"
+  },
+  "env": ".env"
 }
 ```

@@ -126,17 +166,19 @@ Example file directory:

 ```bash
 my-app/
-|-- requirements.txt
-|-- .env
-|-- openai_agent.py
-|-- anthropic_agent.py
-|-- langgraph.json      # configuration file for LangGraph
+├── my_agent # all project code lies within here
+│   ├── utils # utilities for your graph
+│   │   ├── __init__.py
+│   │   ├── tools.py # tools for your graph
+│   │   ├── nodes.py # node functions for you graph
+│   │   └── state.py # state definition of your graph
+│   ├── requirements.txt # package dependencies
+│   ├── __init__.py
+│   └── agent.py # code for constructing your graph
+├── .env # environment variables
+└── langgraph.json # configuration file for LangGraph
 ```

-## Upload to GitHub
-
-To deploy the LangGraph application to LangGraph Cloud, the code must be uploaded to a GitHub repository.
-
 ## Next

-After you setup your repo, it's time to [deploy your app](./cloud.md).
+After you setup your project and place it in a github repo, it's time to [deploy your app](./cloud.md).
@@ -1,16 +1,29 @@
 # How to Set Up a LangGraph Application for Deployment

-A LangGraph application must be configured with a [LangGraph API configuration file](../reference/cli.md#configuration-file) in order to be deployed to LangGraph Cloud (or to be self-hosted). This how-to guide discusses the basic steps to setup a LangGraph application for deployment using `pyproject.toml` to define your package's dependencies. If you prefer using `requirements.txt` for dependency management, check out [this how-to guide](./setup.md).
+A LangGraph application must be configured with a [LangGraph API configuration file](../reference/cli.md#configuration-file) in order to be deployed to LangGraph Cloud (or to be self-hosted). This how-to guide discusses the basic steps to setup a LangGraph application for deployment using `pyproject.toml` to define your package's dependencies. 
+
+This walkthrough is based on [this repository](https://github.com/langchain-ai/langgraph-example), which you can play around with to learn more about how to setup your LangGraph application for deployment.
+
+!!! tip "Setup with requirements.txt"
+  If you prefer using `requirements.txt` for dependency management, check out [this how-to guide](./setup.md).
+
+!!! tip "Setup with a Monorepo"
+    If you are interested in deploying a graph located inside a monorepo, take a look at [this](https://github.com/langchain-ai/langgraph-example-monorepo) repository for an example of how to do so.

 The final repo structure will look something like this:

 ```bash
 my-app/
 ├── my_agent # all project code lies within here
+│   ├── utils # utilities for your graph
+│   │   ├── __init__.py
+│   │   ├── tools.py # tools for your graph
+│   │   ├── nodes.py # node functions for you graph
+│   │   └── state.py # state definition of your graph
 │   ├── __init__.py
-│   └── agent.py # code for your graph
-│-- .env # environment variables
-│-- langgraph.json  # configuration file for LangGraph
+│   └── agent.py # code for constructing your graph
+├── .env # environment variables
+├── langgraph.json  # configuration file for LangGraph
 └── pyproject.toml # dependencies for your project
 ```

@@ -22,13 +35,11 @@ Dependencies can optionally be specified in one of the following files: `pyproje

 The dependencies below will be included in the image, you can also use them in your code, as long as with a compatible version range:
 ```
-langgraph>=0.1.7
-langchain-core>=0.2.7
-orjson>=3.10.1
-langsmith>=0.1.50
-httpx>=0.27.0
-langchain-core>=0.2.8
+langgraph>=0.2.0,<0.3.0
+langchain-core>=0.2.27,<0.3.0
 langsmith>=0.1.63
+orjson>=3.10.1
+httpx>=0.27.0
 tenacity>=8.3.0
 uvicorn>=0.29.0
 sse-starlette>=2.1.0
@@ -36,6 +47,7 @@ uvloop>=0.19.0
 httptools>=0.6.1
 jsonschema-rs>=0.18.0
 croniter>=1.0.1
+structlog>=24.4.0
 ```

 Example `pyproject.toml` file:
@@ -51,7 +63,7 @@ readme = "README.md"

 [tool.poetry.dependencies]
 python = ">=3.9.0,<3.13"
-langgraph = "^0.1.7"
+langgraph = "^0.2.0"
 langchain-fireworks = "^0.1.3"


@@ -64,9 +76,6 @@ Example file directory:

 ```bash
 my-app/
-├── my_agent
-│   ├── __init__.py
-│   └── agent.py
 └── pyproject.toml   # Python packages required for your graph
 ```

@@ -86,10 +95,7 @@ Example file directory:

 ```bash
 my-app/
-├── my_agent
-│   ├── __init__.py
-│   └── agent.py
-|-- .env             # file with environment variables
+├── .env             # file with environment variables
 └── pyproject.toml
 ```

@@ -97,26 +103,35 @@ my-app/

 Implement your graphs! Graphs can be defined in a single file or multiple files. Make note of the variable names of each [CompiledGraph][compiledgraph] to be included in the LangGraph application. The variable names will be used later when creating the [LangGraph API configuration file](../reference/cli.md#configuration-file).

-Example `agent.py` file:
+Example `agent.py` file, which shows how to import from other modules you define (code for the modules is not shown here, please see [this repo](https://github.com/langchain-ai/langgraph-example-pyproject) to see their implementation):

 ```python
 # my_agent/agent.py
-from langchain_fireworks import ChatFireworks
-from langgraph.graph import END, StateGraph, add_messages
-from typing_extensions import TypedDict, Annotated
+from typing import TypedDict, Literal

-model = ChatFireworks(model="accounts/fireworks/models/firefunction-v2", temperature=0)
+from langgraph.graph import StateGraph, END
+from my_agent.utils.nodes import call_model, should_continue, tool_node # import nodes
+from my_agent.utils.state import AgentState # import state

-class State(TypedDict):
-    messages: Annotated[list, add_messages]
+# Define the config
+class GraphConfig(TypedDict):
+    model_name: Literal["anthropic", "openai"]

-graph_workflow = StateGraph(State)
+workflow = StateGraph(AgentState, config_schema=GraphConfig)
+workflow.add_node("agent", call_model)
+workflow.add_node("action", tool_node)
+workflow.set_entry_point("agent")
+workflow.add_conditional_edges(
+    "agent",
+    should_continue,
+    {
+        "continue": "action",
+        "end": END,
+    },
+)
+workflow.add_edge("action", "agent")

-graph_workflow.add_node("agent", model)
-graph_workflow.add_edge("agent", END)
-graph_workflow.set_entry_point("agent")
-
-agent = graph_workflow.compile()
+graph = workflow.compile()
 ```

 !!! warning "Assign `CompiledGraph` to Variable"
@@ -126,10 +141,15 @@ Example file directory:

 ```bash
 my-app/
-├── my_agent
+├── my_agent # all project code lies within here
+│   ├── utils # utilities for your graph
+│   │   ├── __init__.py
+│   │   ├── tools.py # tools for your graph
+│   │   ├── nodes.py # node functions for you graph
+│   │   └── state.py # state definition of your graph
 │   ├── __init__.py
-│   └── agent.py # code for your graph
-|-- .env
+│   └── agent.py # code for constructing your graph
+├── .env
 └── pyproject.toml
 ```

@@ -143,9 +163,9 @@ Example `langgraph.json` file:
 {
  "dependencies": ["."],
  "graphs": {
-    "my_fantastic_agent": "./my_agent/agent.py:agent"
+    "agent": "./my_agent/agent.py:graph"
  },
-  "env": "./.env"
+  "env": ".env"
 }
 ```

@@ -158,18 +178,19 @@ Example file directory:

 ```bash
 my-app/
-├── my_agent
+├── my_agent # all project code lies within here
+│   ├── utils # utilities for your graph
+│   │   ├── __init__.py
+│   │   ├── tools.py # tools for your graph
+│   │   ├── nodes.py # node functions for you graph
+│   │   └── state.py # state definition of your graph
 │   ├── __init__.py
-│   └── agent.py # code for your graph
-│-- .env
-│-- langgraph.json      # configuration file for LangGraph
-└── pyproject.toml
+│   └── agent.py # code for constructing your graph
+├── .env # environment variables
+├── langgraph.json  # configuration file for LangGraph
+└── pyproject.toml # dependencies for your project
 ```

-## Upload to GitHub
-
-To deploy the LangGraph application to LangGraph Cloud, the code must be uploaded to a GitHub repository.
-
 ## Next

-After you setup your repo, it's time to [deploy your app](./cloud.md).
+After you setup your project and place it in a github repo, it's time to [deploy your app](./cloud.md).
@@ -1,13 +1,15 @@
 # Invoke Assistant

-The LangGraph Studio lets you test different configurations and inputs to your graph. The UI allows you to see exactly how your 
+The LangGraph Studio lets you test different configurations and inputs to your graph. It also provides a nice visualization of your graph during execution so it is easy to see which nodes are being run and what the outputs of each individual node are.

 1. The LangGraph Studio UI displays a visualization of the selected assistant.
-    1. In the top-right dropdown menu of the left-hand pane, select an assistant.
+    1. In the top-left dropdown menu of the left-hand pane, select an assistant.
    1. In the bottom of the left-hand pane, edit the `Input` and `Configure` the assistant.
    1. Select `Submit` to invoke the selected assistant.
 1. View output of the invocation in the right-hand pane.

-The following GIF shows these exact steps being carried out:
+The following video shows these exact steps being carried out:

-![Using LangGraph Studio](./img/studio_input.gif)
+<video controls allowfullscreen="true" poster="../img/studio_input_poster.png">
+    <source src="../img/studio_input.mp4" type="video/mp4">
+</video>
@@ -9,6 +9,8 @@ Starting from the <a href="https://smith.langchain.com/" target="_blank">LangSmi
 1. In the top-right corner, select `Open LangGraph Studio`.
 1. [Invoke an assistant](./invoke_studio.md) or [view an existing thread](./threads_studio.md).

-The following GIF shows these exact steps being carried out:
+The following video shows these exact steps being carried out:

-![Using LangGraph Studio](./img/studio_usage.gif)
+<video controls allowfullscreen="true" poster="../img/studio_usage_poster.png">
+    <source src="../img/studio_usage.mp4" type="video/mp4">
+</video>
@@ -6,14 +6,18 @@
 1. View the state of the thread (i.e. the output) in the right-hand pane.
 1. To create a new thread, select `+ New Thread`.

-The following GIF shows these exact steps being carried out:
+The following video shows these exact steps being carried out:

-![Using LangGraph Studio](./img/studio_threads.gif)
+<video controls="true" allowfullscreen="true" poster="../img/studio_threads_poster.png">
+    <source src="../img/studio_threads.mp4" type="video/mp4">
+</video>

 ## Edit Thread State

 The LangGraph Studio UI contains features for editing thread state. Explore these features in the right-hand pane. Select the `Edit` icon, modify the desired state, and then select `Fork` to invoke the assistant with the updated state.

-The following GIF shows how to edit a thread in the studio:
+The following video shows how to edit a thread in the studio:

-![Using LangGraph Studio](./img/studio_forks.gif)
+<video controls allowfullscreen="true" poster="../img/studio_forks_poster.png">
+    <source src="../img/studio_forks.mp4" type="video/mp4">
+</video>
@@ -6,13 +6,14 @@
    - We are actively contributing improvements back to LangGraph informed by our work on LangGraph Cloud.
    - You can always deploy LangGraph applications on your own infrastructure using the open-source LangGraph project.

-!!! danger "Important"
-    LangGraph Cloud is a closed source, paid product in an invite-only stage. We are currently focused on providing high bandwidth support to make our select early customers successful. If you are interested in applying for access, please fill out [this form](https://www.langchain.com/langgraph-cloud-beta).
-
 !!! warning "Under Construction"
    LangGraph Cloud documentation is under construction. Contents may change until general availability.

-![GIF](./how-tos/img/studio_input.gif)
+
+<video controls preload="auto" allowfullscreen="true" poster="how-tos/img/studio_forks_poster.png">
+    <source src="how-tos/img/studio_forks.mp4" type="video/mp4">
+</video>
+

 ## Overview

@@ -13,7 +13,7 @@ The LangGraph CLI requires a JSON configuration file with the following keys:
 | Key | Description |
 | --- | ----------- |
 | `dependencies` | **Required**. Array of dependencies for LangGraph Cloud API server. Dependencies can be one of the following: (1) `"."`, which will look for local Python packages, (2) `pyproject.toml`, `setup.py` or `requirements.txt` in the app directory `"./local_package"`, or (3) a package name. |
-| `graphs` | **Required**. Mapping from graph ID to path where the compiled graph is defined. Example: `./your_package/your_file.py:variable`, where `variable` is an instance of `langgraph.graph.graph.CompiledGraph`. |
+| `graphs` | **Required**. Mapping from graph ID to path where the compiled graph or a function that makes a graph is defined. Example: <ul><li>`./your_package/your_file.py:variable`, where `variable` is an instance of `langgraph.graph.state.CompiledStateGraph`</li><li>`./your_package/your_file.py:make_graph`, where `make_graph` is a function that takes a config dictionary (`langchain_core.runnables.RunnableConfig`) and creates an instance of `langgraph.graph.state.StateGraph` / `langgraph.graph.state.CompiledStateGraph`.</li></ul> |
 | `env` | Path to `.env` file or a mapping from environment variable to its value. |
 | `python_version` | `3.11` or `3.12`. Defaults to `3.11`. |
 | `pip_config_file`| Path to `pip` config file. |
@@ -49,7 +49,7 @@ Example:
        "."
    ],
    "graphs": {
-        "my_graph_id": "./your_package/your_file.py:variable"
+        "my_graph_id": "./your_package/your_file.py:make_graph"
    },
    "env": {
        "OPENAI_API_KEY": "secret-key"
@@ -56,6 +56,25 @@ This is a pretty advanced interaction pattern. In this interaction pattern, the

 See [this guide](../how-tos/human_in_the_loop/time-travel.ipynb) for how to do this in LangGraph.

+## Review Tool Calls
+
+This is a specific type of human-in-the-loop interaction but it's worth calling out because it is so common. A lot of agent decisions are made via tool calling, so having a clear UX for reviewing tool calls is handy.
+
+A tool call consists of:
+- The name of the tool to call
+- Arguments to pass to the tool
+
+Note that these tool calls can obviously be used for actually calling functions, but they can also be used for other purposes, like to route the agent in a specific direction.
+You will want to review the tool call for both of these use cases.
+
+When reviewing tool calls, there are few actions you may want to take.
+
+1. Approve the tool call (and let the agent continue on its way)
+2. Manually change the tool call, either the tool name or the tool arguments (and let the agent continue on its way after that)
+3. Leave feedback on the tool call. This differs from (2) in that you are not changing the tool call directly, but rather leaving natural language feedback suggesting the LLM call it differently (or call a different tool). You could do this by either adding a `ToolMessage` and having the feedback be the result of the tool call, or by adding a `ToolMessage` (that simulates an error) and then a `HumanMessage` (with the feedback).
+
+See [this guide](../how-tos/human_in_the_loop/review-tool-calls.ipynb) for how to do this in LangGraph.
+
 ## Map-Reduce

 A common pattern in agents is to generate a list of objects, do some work on each of those objects, and then combine the results. This is very similar to the common [map-reduce](https://en.wikipedia.org/wiki/MapReduce) operation. This can be tricky for a few reasons. First, it can be tough to define a structured graph ahead of time because the length of the list of objects may be unknown. Second, in order to do this map-reduce you need multiple versions of the state to exist... but the graph shares a common shared state, so how can this be?
@@ -20,7 +20,7 @@ Low Level Concepts
 - [State](low_level.md#state)
    - [Schema](low_level.md#schema)
    - [Reducers](low_level.md#reducers)
-    - [MessageState](low_level.md#messagestate)
+    - [MessageState](low_level.md#working-with-messages-in-graph-state)
 - [Nodes](low_level.md#nodes)
    - [`START` node](low_level.md#start-node)
    - [`END` node](low_level.md#end-node)
@@ -49,9 +49,14 @@ The main documented way to specify the schema of a graph is by using `TypedDict`
 By default, the graph will have the same input and output schemas. If you want to change this, you can also specify explicit input and output schemas directly. This is useful when you have a lot of keys, and some are explicitly for input and others for output. See the [notebook here](../how-tos/input_output_schema.ipynb) for how to use.

 By default, all nodes in the graph will share the same state. This means that they will read and write to the same state channels. It is possible to have nodes write to private state channels inside the graph for internal node communication - see [this notebook](../how-tos/pass_private_state.ipynb) for how to do that.
+
 ### Reducers

-Reducers are key to understanding how updates from nodes are applied to the `State`. Each key in the `State` has its own independent reducer function. If no reducer function is explicitly specified then it is assumed that all updates to that key should override it. Let's take a look at a few examples to understand them better.
+Reducers are key to understanding how updates from nodes are applied to the `State`. Each key in the `State` has its own independent reducer function. If no reducer function is explicitly specified then it is assumed that all updates to that key should override it. There are a few different types of reducers, starting with the default type of reducer:
+
+#### Default Reducer
+
+These two examples show how to use the default reducer:

 **Example A:**

@@ -78,22 +83,48 @@ class State(TypedDict):

 In this example, we've used the `Annotated` type to specify a reducer function (`operator.add`) for the second key (`bar`). Note that the first key remains unchanged. Let's assume the input to the graph is `{"foo": 1, "bar": ["hi"]}`. Let's then assume the first `Node` returns `{"foo": 2}`. This is treated as an update to the state. Notice that the `Node` does not need to return the whole `State` schema - just an update. After applying this update, the `State` would then be `{"foo": 2, "bar": ["hi"]}`. If the second node returns `{"bar": ["bye"]}` then the `State` would then be `{"foo": 2, "bar": ["hi", "bye"]}`. Notice here that the `bar` key is updated by adding the two lists together.

-### MessageState
+#### Context Reducer

-`MessageState` is one of the few opinionated components in LangGraph. `MessageState` is a special state designed to make it easy to use a list of messages as a key in your state. Specifically, `MessageState` is defined as:
+You can use `Context` channels to define shared resources (such as database connections) that are managed outside of your graph's nodes and excluded from checkpointing. The context manager provided to the Context channel is entered before the first step of the graph execution and exited after the last step, allowing you to set up and clean up resources for the duration of the graph invocation. Read this [how to](https://langchain-ai.github.io/langgraph/how-tos/state-context-key) to see an example of using the `Context` channel in your graph.
+
+### Working with Messages in Graph State
+
+#### Why use messages?
+
+Most modern LLM providers have a chat model interface that accepts a list of messages as input. LangChain's [`ChatModel`](https://python.langchain.com/v0.2/docs/concepts/#chat-models) in particular accepts a list of `Message` objects as inputs. These messages come in a variety of forms such as `HumanMessage` (user input) or `AIMessage` (LLM response). To read more about what message objects are, please refer to [this](https://python.langchain.com/v0.2/docs/concepts/#messages) conceptual guide.
+
+#### Using Messages in your Graph
+
+In many cases, it is helpful to store prior conversation history as a list of messages in your graph state. To do so, we can add a key (channel) to the graph state that stores a list of `Message` objects and annotate it with a reducer function (see `messages` key in the example below). The reducer function is vital to telling the graph how to update the list of `Message` objects in the state with each state update (for example, when a node sends an update). If you don't specify a reducer, every state update will overwrite the list of messages with the most recently provided value. If you wanted to simply append messages to the existing list, you could use `operator.add` as a reducer.
+
+However, you might also want to manually update messages in your graph state (e.g. human-in-the-loop). If you were to use `operator.add`, the manual state updates you send to the graph would be appended to the existing list of messages, instead of updating existing messages. To avoid that, you need a reducer that can keep track of message IDs and overwrite existing messages, if updated. To achieve this, you can use the prebuilt `add_messages` function. For brand new messages, it will simply append to existing list, but it will also handle the updates for existing messages correctly.
+
+#### Serialization
+
+In addition to keeping track of message IDs, the `add_messages` function will also try to deserialize messages into LangChain `Message` objects whenever a state update is received on the `messages` channel. See more information on LangChain serialization/deserialization [here](https://python.langchain.com/v0.2/docs/how_to/serialization/). This allows sending graph inputs / state updates in the following format:
+
+```python
+# this is supported
+{"messages": [HumanMessage(content="message")]}
+
+# and this is also supported
+{"messages": [{"type": "human", "content": "message"}]}
+```
+
+Since the state updates are always deserialized into LangChain `Messages` when using `add_messages`, you should use dot notation to access message attributes, like `state["messages"][-1].content`. Below is an example of a graph that uses `add_messages` as it's reducer function.

 ```python
 from langchain_core.messages import AnyMessage
 from langgraph.graph.message import add_messages
 from typing import Annotated, TypedDict

-class MessagesState(TypedDict):
+class GraphState(TypedDict):
    messages: Annotated[list[AnyMessage], add_messages]
 ```

-What this is doing is creating a `TypedDict` with a single key: `messages`. This is a list of `Message` objects, with `add_messages` as a reducer. `add_messages` basically adds messages to the existing list (it also does some nice extra things, like convert from OpenAI message format to the standard LangChain message format, handle updates based on message IDs, etc).
+#### MessagesState

-We often see a list of messages being a key component of state, so this prebuilt state is intended to make it easy to use messages. Typically, there is more state to track than just messages, so we see people subclass this state and add more fields, like:
+Since having a list of messages in your state is so common, there exists a prebuilt state called `MessagesState` which makes it easy to use messages. `MessagesState` is defined with a single `messages` key which is a list of `AnyMessage` objects and uses the `add_messages` reducer. Typically, there is more state to track than just messages, so we see people subclass this state and add more fields, like:

 ```python
 from langgraph.graph import MessagesState
@@ -25,7 +25,7 @@ LangGraph makes it easy to persist state across graph runs. The guide below show
 - [How to manage conversation history](memory/manage-conversation-history.ipynb)
 - [How to delete messages](memory/delete-messages.ipynb)
 - [How to add summary conversation memory](memory/add-summary-conversation-history.ipynb)
- [How to create a custom checkpointer using Postgres](persistence_postgres.ipynb)
+- [How to use Postgres checkpointer for persistence](persistence_postgres.ipynb)
 - [How to create a custom checkpointer using MongoDB](persistence_mongodb.ipynb)
 - [How to create a custom checkpointer using Redis](persistence_redis.ipynb)

@@ -38,6 +38,7 @@ These guides cover common examples of that.
 - [How to edit graph state](human_in_the_loop/edit-graph-state.ipynb)
 - [How to wait for user input](human_in_the_loop/wait-user-input.ipynb)
 - [How to view and update past graph state](human_in_the_loop/time-travel.ipynb)
+- [Review tool calls](human_in_the_loop/review-tool-calls.ipynb)

 ## Streaming

@@ -60,6 +61,14 @@ These guides show how to use different streaming modes.
 - [How to handle tool calling errors](tool-calling-errors.ipynb)
 - [How to pass graph state to tools](pass-run-time-values-to-tools.ipynb)
 - [How to pass config to tools](pass-config-to-tools.ipynb)
+- [How to handle large numbers of tools](many-tools.ipynb)
+
+## State Management
+
+- [Use Pydantic model as state](state-model.ipynb)
+- [Use a context object in state](state-context-key.ipynb)
+- [Have a separate input and output schema](input_output_schema.ipynb)
+- [Pass private state between nodes inside the graph](pass_private_state.ipynb)

 ## Other

@@ -7,6 +7,8 @@ You can [compile][langgraph.graph.MessageGraph.compile] any LangGraph workflow w
 - Resilience for long-running, error-prone agents
 - Time travel retry and branch from a previous checkpoint

+Key checkpointer interfaces and primitives are defined in [`langgraph_checkpoint`](https://github.com/langchain-ai/langgraph/tree/main/libs/checkpoint) library.
+
 ### Checkpoint

 ::: langgraph.checkpoint.base.Checkpoint
@@ -21,7 +23,7 @@ You can [compile][langgraph.graph.MessageGraph.compile] any LangGraph workflow w

 ### SerializerProtocol

-::: langgraph.checkpoint.SerializerProtocol
+::: langgraph.checkpoint.base.SerializerProtocol

 ## Implementations

@@ -33,9 +35,20 @@ LangGraph also natively provides the following checkpoint implementations.

 ### AsyncSqliteSaver

-::: langgraph.checkpoint.aiosqlite.AsyncSqliteSaver
+::: langgraph.checkpoint.sqlite.aio.AsyncSqliteSaver

 ### SqliteSaver

 ::: langgraph.checkpoint.sqlite.SqliteSaver
+
+### AsyncPostgresSaver
+
+::: langgraph.checkpoint.postgres.aio.AsyncPostgresSaver
+
+### PostgresSaver
+
+::: langgraph.checkpoint.postgres.PostgresSaver
+handler: python
+
+
 handler: python
@@ -134,7 +134,7 @@ nav:
          - Manage conversation history: how-tos/memory/manage-conversation-history.ipynb
          - Delete messages: how-tos/memory/delete-messages.ipynb
          - Add summary of the conversation history: how-tos/memory/add-summary-conversation-history.ipynb
-          - Create custom checkpointer using Postgres: how-tos/persistence_postgres.ipynb
+          - Use Postgres checkpointer for persistence: how-tos/persistence_postgres.ipynb
          - Create custom checkpointer using MongoDB: how-tos/persistence_mongodb.ipynb
          - Create custom checkpointer using Redis: how-tos/persistence_redis.ipynb
      - Human-in-the-loop:
@@ -142,6 +142,7 @@ nav:
          - Wait for user input: how-tos/human_in_the_loop/wait-user-input.ipynb
          - View and update past graph state: how-tos/human_in_the_loop/time-travel.ipynb
          - Edit graph state: how-tos/human_in_the_loop/edit-graph-state.ipynb
+          - Review tool calls: how-tos/human_in_the_loop/review-tool-calls.ipynb
      - Streaming:
          - Stream full state: how-tos/stream-values.ipynb
          - Stream state updates: how-tos/stream-updates.ipynb
@@ -157,6 +158,7 @@ nav:
          - Handle tool calling errors: how-tos/tool-calling-errors.ipynb
          - Pass graph state to tools: how-tos/pass-run-time-values-to-tools.ipynb
          - Pass config to tools: how-tos/pass-config-to-tools.ipynb
+          - Handle many tools: how-tos/many-tools.ipynb
      - State Management:
          - Use Pydantic model as state: how-tos/state-model.ipynb
          - Use a context object in state: how-tos/state-context-key.ipynb
@@ -189,10 +191,12 @@ nav:
          - Quick Start: "cloud/quick_start.md"
      - How-to Guides: 
          - "cloud/how-tos/index.md"
-          - Deployment:
+          - Setup:
              - Setup App: "cloud/deployment/setup.md"
              - Setup App (pyproject.toml): "cloud/deployment/setup_pyproject.md"
+              - Rebuild Graph at Runtime: "cloud/deployment/graph_rebuild.md"
              - Test App Locally: "cloud/deployment/test_locally.md"
+          - Deployment:
              - Deploy to Cloud: "cloud/deployment/cloud.md"
              - Self-Host: "cloud/deployment/self_hosted.md"
          - Streaming:
@@ -32,7 +32,10 @@
    "scrolled": true
   },
   "outputs": [],
-   "source": ["%%capture --no-stderr\n%pip install -U langgraph langchain-community langchain-openai scikit-learn"]
+   "source": [
+    "%%capture --no-stderr\n",
+    "%pip install -U langgraph langchain-community langchain-openai scikit-learn"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -48,7 +51,15 @@
   "id": "3d1ef253-6b0c-4481-868c-e1fe84f2c8ff",
   "metadata": {},
   "outputs": [],
-   "source": ["import requests\n\nurl = \"https://storage.googleapis.com/benchmarks-artifacts/chinook/Chinook.db\"\nresponse = requests.get(url)\n\nwith open(\"Chinook.db\", \"wb\") as file:\n    file.write(response.content)"]
+   "source": [
+    "import requests\n",
+    "\n",
+    "url = \"https://storage.googleapis.com/benchmarks-artifacts/chinook/Chinook.db\"\n",
+    "response = requests.get(url)\n",
+    "\n",
+    "with open(\"Chinook.db\", \"wb\") as file:\n",
+    "    file.write(response.content)"
+   ]
  },
  {
   "cell_type": "code",
@@ -77,7 +88,12 @@
     "output_type": "execute_result"
    }
   ],
-   "source": ["from langchain_community.utilities import SQLDatabase\n\ndb = SQLDatabase.from_uri(\"sqlite:///Chinook.db\")\ndb.get_usable_table_names()"]
+   "source": [
+    "from langchain_community.utilities import SQLDatabase\n",
+    "\n",
+    "db = SQLDatabase.from_uri(\"sqlite:///Chinook.db\")\n",
+    "db.get_usable_table_names()"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -96,7 +112,11 @@
   "id": "d9ea4e80-30e6-4d46-b480-35f0be2fb055",
   "metadata": {},
   "outputs": [],
-   "source": ["from langchain_openai import ChatOpenAI\n\nmodel = ChatOpenAI(temperature=0, streaming=True, model=\"gpt-4o\")"]
+   "source": [
+    "from langchain_openai import ChatOpenAI\n",
+    "\n",
+    "model = ChatOpenAI(temperature=0, streaming=True, model=\"gpt-4o\")"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -118,7 +138,9 @@
   "id": "ea958e9f-ab1f-49b5-bd85-16332055297c",
   "metadata": {},
   "outputs": [],
-   "source": ["from langchain_core.messages import HumanMessage, SystemMessage"]
+   "source": [
+    "from langchain_core.messages import HumanMessage, SystemMessage"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -137,7 +159,12 @@
   "id": "975b039a",
   "metadata": {},
   "outputs": [],
-   "source": ["# This tool is given to the agent to look up information about a customer\ndef get_customer_info(customer_id: int):\n    \"\"\"Look up customer info given their ID. ALWAYS make sure you have the customer ID before invoking this.\"\"\"\n    return db.run(f\"SELECT * FROM Customer WHERE CustomerID = {customer_id};\")"]
+   "source": [
+    "# This tool is given to the agent to look up information about a customer\n",
+    "def get_customer_info(customer_id: int):\n",
+    "    \"\"\"Look up customer info given their ID. ALWAYS make sure you have the customer ID before invoking this.\"\"\"\n",
+    "    return db.run(f\"SELECT * FROM Customer WHERE CustomerID = {customer_id};\")"
+   ]
  },
  {
   "cell_type": "code",
@@ -145,7 +172,20 @@
   "id": "1d5fa446",
   "metadata": {},
   "outputs": [],
-   "source": ["customer_prompt = \"\"\"Your job is to help a user update their profile.\n\nYou only have certain tools you can use. These tools require specific input. If you don't know the required input, then ask the user for it.\n\nIf you are unable to help the user, you can \"\"\"\n\n\ndef get_customer_messages(messages):\n    return [SystemMessage(content=customer_prompt)] + messages\n\n\ncustomer_chain = get_customer_messages | model.bind_tools([get_customer_info])"]
+   "source": [
+    "customer_prompt = \"\"\"Your job is to help a user update their profile.\n",
+    "\n",
+    "You only have certain tools you can use. These tools require specific input. If you don't know the required input, then ask the user for it.\n",
+    "\n",
+    "If you are unable to help the user, you can \"\"\"\n",
+    "\n",
+    "\n",
+    "def get_customer_messages(messages):\n",
+    "    return [SystemMessage(content=customer_prompt)] + messages\n",
+    "\n",
+    "\n",
+    "customer_chain = get_customer_messages | model.bind_tools([get_customer_info])"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -166,7 +206,19 @@
   "id": "a8604a3b-b484-4b2b-a914-4236cb98c524",
   "metadata": {},
   "outputs": [],
-   "source": ["from langchain_community.vectorstores import SKLearnVectorStore\nfrom langchain_openai import OpenAIEmbeddings\n\nartists = db._execute(\"select * from Artist\")\nsongs = db._execute(\"select * from Track\")\nartist_retriever = SKLearnVectorStore.from_texts(\n    [a[\"Name\"] for a in artists], OpenAIEmbeddings(), metadatas=artists\n).as_retriever()\nsong_retriever = SKLearnVectorStore.from_texts(\n    [a[\"Name\"] for a in songs], OpenAIEmbeddings(), metadatas=songs\n).as_retriever()"]
+   "source": [
+    "from langchain_community.vectorstores import SKLearnVectorStore\n",
+    "from langchain_openai import OpenAIEmbeddings\n",
+    "\n",
+    "artists = db._execute(\"select * from Artist\")\n",
+    "songs = db._execute(\"select * from Track\")\n",
+    "artist_retriever = SKLearnVectorStore.from_texts(\n",
+    "    [a[\"Name\"] for a in artists], OpenAIEmbeddings(), metadatas=artists\n",
+    ").as_retriever()\n",
+    "song_retriever = SKLearnVectorStore.from_texts(\n",
+    "    [a[\"Name\"] for a in songs], OpenAIEmbeddings(), metadatas=songs\n",
+    ").as_retriever()"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -182,7 +234,16 @@
   "id": "0a2a2b74",
   "metadata": {},
   "outputs": [],
-   "source": ["def get_albums_by_artist(artist):\n    \"\"\"Get albums by an artist (or similar artists).\"\"\"\n    docs = artist_retriever.get_relevant_documents(artist)\n    artist_ids = \", \".join([str(d.metadata[\"ArtistId\"]) for d in docs])\n    return db.run(\n        f\"SELECT Title, Name FROM Album LEFT JOIN Artist ON Album.ArtistId = Artist.ArtistId WHERE Album.ArtistId in ({artist_ids});\",\n        include_columns=True,\n    )"]
+   "source": [
+    "def get_albums_by_artist(artist):\n",
+    "    \"\"\"Get albums by an artist (or similar artists).\"\"\"\n",
+    "    docs = artist_retriever.get_relevant_documents(artist)\n",
+    "    artist_ids = \", \".join([str(d.metadata[\"ArtistId\"]) for d in docs])\n",
+    "    return db.run(\n",
+    "        f\"SELECT Title, Name FROM Album LEFT JOIN Artist ON Album.ArtistId = Artist.ArtistId WHERE Album.ArtistId in ({artist_ids});\",\n",
+    "        include_columns=True,\n",
+    "    )"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -198,7 +259,16 @@
   "id": "da533f50",
   "metadata": {},
   "outputs": [],
-   "source": ["def get_tracks_by_artist(artist):\n    \"\"\"Get songs by an artist (or similar artists).\"\"\"\n    docs = artist_retriever.invoke(artist)\n    artist_ids = \", \".join([str(d.metadata[\"ArtistId\"]) for d in docs])\n    return db.run(\n        f\"SELECT Track.Name as SongName, Artist.Name as ArtistName FROM Album LEFT JOIN Artist ON Album.ArtistId = Artist.ArtistId LEFT JOIN Track ON Track.AlbumId = Album.AlbumId WHERE Album.ArtistId in ({artist_ids});\",\n        include_columns=True,\n    )"]
+   "source": [
+    "def get_tracks_by_artist(artist):\n",
+    "    \"\"\"Get songs by an artist (or similar artists).\"\"\"\n",
+    "    docs = artist_retriever.invoke(artist)\n",
+    "    artist_ids = \", \".join([str(d.metadata[\"ArtistId\"]) for d in docs])\n",
+    "    return db.run(\n",
+    "        f\"SELECT Track.Name as SongName, Artist.Name as ArtistName FROM Album LEFT JOIN Artist ON Album.ArtistId = Artist.ArtistId LEFT JOIN Track ON Track.AlbumId = Album.AlbumId WHERE Album.ArtistId in ({artist_ids});\",\n",
+    "        include_columns=True,\n",
+    "    )"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -214,7 +284,11 @@
   "id": "b3c07010",
   "metadata": {},
   "outputs": [],
-   "source": ["def check_for_songs(song_title):\n    \"\"\"Check if a song exists by its name.\"\"\"\n    return song_retriever.invoke(song_title)"]
+   "source": [
+    "def check_for_songs(song_title):\n",
+    "    \"\"\"Check if a song exists by its name.\"\"\"\n",
+    "    return song_retriever.invoke(song_title)"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -230,7 +304,23 @@
   "id": "72a14d5c",
   "metadata": {},
   "outputs": [],
-   "source": ["song_system_message = \"\"\"Your job is to help a customer find any songs they are looking for. \n\nYou only have certain tools you can use. If a customer asks you to look something up that you don't know how, politely tell them what you can help with.\n\nWhen looking up artists and songs, sometimes the artist/song will not be found. In that case, the tools will return information \\\non similar songs and artists. This is intentional, it is not the tool messing up.\"\"\"\n\n\ndef get_song_messages(messages):\n    return [SystemMessage(content=song_system_message)] + messages\n\n\nsong_recc_chain = get_song_messages | model.bind_tools(\n    [get_albums_by_artist, get_tracks_by_artist, check_for_songs]\n)"]
+   "source": [
+    "song_system_message = \"\"\"Your job is to help a customer find any songs they are looking for. \n",
+    "\n",
+    "You only have certain tools you can use. If a customer asks you to look something up that you don't know how, politely tell them what you can help with.\n",
+    "\n",
+    "When looking up artists and songs, sometimes the artist/song will not be found. In that case, the tools will return information \\\n",
+    "on similar songs and artists. This is intentional, it is not the tool messing up.\"\"\"\n",
+    "\n",
+    "\n",
+    "def get_song_messages(messages):\n",
+    "    return [SystemMessage(content=song_system_message)] + messages\n",
+    "\n",
+    "\n",
+    "song_recc_chain = get_song_messages | model.bind_tools(\n",
+    "    [get_albums_by_artist, get_tracks_by_artist, check_for_songs]\n",
+    ")"
+   ]
  },
  {
   "cell_type": "code",
@@ -249,7 +339,10 @@
     "output_type": "execute_result"
    }
   ],
-   "source": ["msgs = [HumanMessage(content=\"hi! can you help me find songs by amy whinehouse?\")]\nsong_recc_chain.invoke(msgs)"]
+   "source": [
+    "msgs = [HumanMessage(content=\"hi! can you help me find songs by amy whinehouse?\")]\n",
+    "song_recc_chain.invoke(msgs)"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -267,7 +360,32 @@
   "id": "73e74268",
   "metadata": {},
   "outputs": [],
-   "source": ["from langchain_core.messages import AIMessage, HumanMessage, SystemMessage\nfrom langchain_core.pydantic_v1 import BaseModel, Field\n\n\nclass Router(BaseModel):\n    \"\"\"Call this if you are able to route the user to the appropriate representative.\"\"\"\n\n    choice: str = Field(description=\"should be one of: music, customer\")\n\n\nsystem_message = \"\"\"Your job is to help as a customer service representative for a music store.\n\nYou should interact politely with customers to try to figure out how you can help. You can help in a few ways:\n\n- Updating user information: if a customer wants to update the information in the user database. Call the router with `customer`\n- Recommending music: if a customer wants to find some music or information about music. Call the router with `music`\n\nIf the user is asking or wants to ask about updating or accessing their information, send them to that route.\nIf the user is asking or wants to ask about music, send them to that route.\nOtherwise, respond.\"\"\"\n\n\ndef get_messages(messages):\n    return [SystemMessage(content=system_message)] + messages"]
+   "source": [
+    "from langchain_core.messages import AIMessage, HumanMessage, SystemMessage\n",
+    "from langchain_core.pydantic_v1 import BaseModel, Field\n",
+    "\n",
+    "\n",
+    "class Router(BaseModel):\n",
+    "    \"\"\"Call this if you are able to route the user to the appropriate representative.\"\"\"\n",
+    "\n",
+    "    choice: str = Field(description=\"should be one of: music, customer\")\n",
+    "\n",
+    "\n",
+    "system_message = \"\"\"Your job is to help as a customer service representative for a music store.\n",
+    "\n",
+    "You should interact politely with customers to try to figure out how you can help. You can help in a few ways:\n",
+    "\n",
+    "- Updating user information: if a customer wants to update the information in the user database. Call the router with `customer`\n",
+    "- Recommending music: if a customer wants to find some music or information about music. Call the router with `music`\n",
+    "\n",
+    "If the user is asking or wants to ask about updating or accessing their information, send them to that route.\n",
+    "If the user is asking or wants to ask about music, send them to that route.\n",
+    "Otherwise, respond.\"\"\"\n",
+    "\n",
+    "\n",
+    "def get_messages(messages):\n",
+    "    return [SystemMessage(content=system_message)] + messages"
+   ]
  },
  {
   "cell_type": "code",
@@ -275,7 +393,9 @@
   "id": "ddf27314",
   "metadata": {},
   "outputs": [],
-   "source": ["chain = get_messages | model.bind_tools([Router])"]
+   "source": [
+    "chain = get_messages | model.bind_tools([Router])"
+   ]
  },
  {
   "cell_type": "code",
@@ -294,7 +414,10 @@
     "output_type": "execute_result"
    }
   ],
-   "source": ["msgs = [HumanMessage(content=\"hi! can you help me find a good song?\")]\nchain.invoke(msgs)"]
+   "source": [
+    "msgs = [HumanMessage(content=\"hi! can you help me find a good song?\")]\n",
+    "chain.invoke(msgs)"
+   ]
  },
  {
   "cell_type": "code",
@@ -313,7 +436,10 @@
     "output_type": "execute_result"
    }
   ],
-   "source": ["msgs = [HumanMessage(content=\"hi! what's the email you have for me?\")]\nchain.invoke(msgs)"]
+   "source": [
+    "msgs = [HumanMessage(content=\"hi! what's the email you have for me?\")]\n",
+    "chain.invoke(msgs)"
+   ]
  },
  {
   "cell_type": "code",
@@ -321,7 +447,15 @@
   "id": "bd6ddd8b-7500-46a7-811d-3bcb937bda51",
   "metadata": {},
   "outputs": [],
-   "source": ["from langchain_core.messages import AIMessage\n\n\ndef add_name(message, name):\n    _dict = message.dict()\n    _dict[\"name\"] = name\n    return AIMessage(**_dict)"]
+   "source": [
+    "from langchain_core.messages import AIMessage\n",
+    "\n",
+    "\n",
+    "def add_name(message, name):\n",
+    "    _dict = message.dict()\n",
+    "    _dict[\"name\"] = name\n",
+    "    return AIMessage(**_dict)"
+   ]
  },
  {
   "cell_type": "code",
@@ -329,7 +463,45 @@
   "id": "27494de5-8345-4c23-bc0e-81e0dd5d47d8",
   "metadata": {},
   "outputs": [],
-   "source": ["import json\n\nfrom langgraph.graph import END, START\n\n\ndef _get_last_ai_message(messages):\n    for m in messages[::-1]:\n        if isinstance(m, AIMessage):\n            return m\n    return None\n\n\ndef _is_tool_call(msg):\n    return hasattr(msg, \"additional_kwargs\") and \"tool_calls\" in msg.additional_kwargs\n\n\ndef _route(messages):\n    last_message = messages[-1]\n    if isinstance(last_message, AIMessage):\n        if not last_message.tool_calls:\n            return END\n        else:\n            if last_message.name == \"general\":\n                if len(last_message.tool_calls) > 1:\n                    raise ValueError(\"Too many tools\")\n                return last_message.tool_calls[0][\"args\"][\"choice\"]\n            else:\n                return \"tools\"\n    last_m = _get_last_ai_message(messages)\n    if last_m is None:\n        return \"general\"\n    if last_m.name == \"music\":\n        return \"music\"\n    elif last_m.name == \"customer\":\n        return \"customer\"\n    else:\n        return \"general\""]
+   "source": [
+    "import json\n",
+    "\n",
+    "from langgraph.graph import END, START\n",
+    "\n",
+    "\n",
+    "def _get_last_ai_message(messages):\n",
+    "    for m in messages[::-1]:\n",
+    "        if isinstance(m, AIMessage):\n",
+    "            return m\n",
+    "    return None\n",
+    "\n",
+    "\n",
+    "def _is_tool_call(msg):\n",
+    "    return hasattr(msg, \"additional_kwargs\") and \"tool_calls\" in msg.additional_kwargs\n",
+    "\n",
+    "\n",
+    "def _route(messages):\n",
+    "    last_message = messages[-1]\n",
+    "    if isinstance(last_message, AIMessage):\n",
+    "        if not last_message.tool_calls:\n",
+    "            return END\n",
+    "        else:\n",
+    "            if last_message.name == \"general\":\n",
+    "                if len(last_message.tool_calls) > 1:\n",
+    "                    raise ValueError(\"Too many tools\")\n",
+    "                return last_message.tool_calls[0][\"args\"][\"choice\"]\n",
+    "            else:\n",
+    "                return \"tools\"\n",
+    "    last_m = _get_last_ai_message(messages)\n",
+    "    if last_m is None:\n",
+    "        return \"general\"\n",
+    "    if last_m.name == \"music\":\n",
+    "        return \"music\"\n",
+    "    elif last_m.name == \"customer\":\n",
+    "        return \"customer\"\n",
+    "    else:\n",
+    "        return \"general\""
+   ]
  },
  {
   "cell_type": "code",
@@ -337,7 +509,12 @@
   "id": "8aec704a-46fe-4fb3-bdee-11c3bbffc370",
   "metadata": {},
   "outputs": [],
-   "source": ["from langgraph.prebuilt import ToolNode\n\ntools = [get_albums_by_artist, get_tracks_by_artist, check_for_songs, get_customer_info]\ntool_node = ToolNode(tools)"]
+   "source": [
+    "from langgraph.prebuilt import ToolNode\n",
+    "\n",
+    "tools = [get_albums_by_artist, get_tracks_by_artist, check_for_songs, get_customer_info]\n",
+    "tool_node = ToolNode(tools)"
+   ]
  },
  {
   "cell_type": "code",
@@ -345,7 +522,16 @@
   "id": "4d5b75c6-73e0-4922-a765-a15be63f869e",
   "metadata": {},
   "outputs": [],
-   "source": ["def _filter_out_routes(messages):\n    ms = []\n    for m in messages:\n        if _is_tool_call(m):\n            if m.name == \"general\":\n                continue\n        ms.append(m)\n    return ms"]
+   "source": [
+    "def _filter_out_routes(messages):\n",
+    "    ms = []\n",
+    "    for m in messages:\n",
+    "        if _is_tool_call(m):\n",
+    "            if m.name == \"general\":\n",
+    "                continue\n",
+    "        ms.append(m)\n",
+    "    return ms"
+   ]
  },
  {
   "cell_type": "code",
@@ -353,7 +539,13 @@
   "id": "fd4dbf98-dbb3-411a-bad6-2bb334072aaf",
   "metadata": {},
   "outputs": [],
-   "source": ["from functools import partial\n\ngeneral_node = _filter_out_routes | chain | partial(add_name, name=\"general\")\nmusic_node = _filter_out_routes | song_recc_chain | partial(add_name, name=\"music\")\ncustomer_node = _filter_out_routes | customer_chain | partial(add_name, name=\"customer\")"]
+   "source": [
+    "from functools import partial\n",
+    "\n",
+    "general_node = _filter_out_routes | chain | partial(add_name, name=\"general\")\n",
+    "music_node = _filter_out_routes | song_recc_chain | partial(add_name, name=\"music\")\n",
+    "customer_node = _filter_out_routes | customer_chain | partial(add_name, name=\"customer\")"
+   ]
  },
  {
   "cell_type": "code",
@@ -361,7 +553,33 @@
   "id": "dcade924",
   "metadata": {},
   "outputs": [],
-   "source": ["from langgraph.checkpoint.sqlite import SqliteSaver\n\nfrom langgraph.graph import MessageGraph\n\nmemory = SqliteSaver.from_conn_string(\":memory:\")\ngraph = MessageGraph()\nnodes = {\n    \"general\": \"general\",\n    \"music\": \"music\",\n    END: END,\n    \"tools\": \"tools\",\n    \"customer\": \"customer\",\n}\n# Define a new graph\nworkflow = MessageGraph()\nworkflow.add_node(\"general\", general_node)\nworkflow.add_node(\"music\", music_node)\nworkflow.add_node(\"customer\", customer_node)\nworkflow.add_node(\"tools\", tool_node)\nworkflow.add_conditional_edges(\"general\", _route, nodes)\nworkflow.add_conditional_edges(\"tools\", _route, nodes)\nworkflow.add_conditional_edges(\"music\", _route, nodes)\nworkflow.add_conditional_edges(\"customer\", _route, nodes)\nworkflow.add_conditional_edges(START, _route, nodes)\ngraph = workflow.compile()"]
+   "source": [
+    "from langgraph.checkpoint.memory import MemorySaver\n",
+    "\n",
+    "from langgraph.graph import MessageGraph\n",
+    "\n",
+    "memory = MemorySaver()\n",
+    "graph = MessageGraph()\n",
+    "nodes = {\n",
+    "    \"general\": \"general\",\n",
+    "    \"music\": \"music\",\n",
+    "    END: END,\n",
+    "    \"tools\": \"tools\",\n",
+    "    \"customer\": \"customer\",\n",
+    "}\n",
+    "# Define a new graph\n",
+    "workflow = MessageGraph()\n",
+    "workflow.add_node(\"general\", general_node)\n",
+    "workflow.add_node(\"music\", music_node)\n",
+    "workflow.add_node(\"customer\", customer_node)\n",
+    "workflow.add_node(\"tools\", tool_node)\n",
+    "workflow.add_conditional_edges(\"general\", _route, nodes)\n",
+    "workflow.add_conditional_edges(\"tools\", _route, nodes)\n",
+    "workflow.add_conditional_edges(\"music\", _route, nodes)\n",
+    "workflow.add_conditional_edges(\"customer\", _route, nodes)\n",
+    "workflow.add_conditional_edges(START, _route, nodes)\n",
+    "graph = workflow.compile()"
+   ]
  },
  {
   "cell_type": "code",
@@ -370,7 +588,7 @@
   "metadata": {},
   "outputs": [
    {
-     "name": "stdin",
+     "name": "stdout",
     "output_type": "stream",
     "text": [
      "User (q/Q to quit):  what music do you have?\n"
@@ -395,7 +613,7 @@
     ]
    },
    {
-     "name": "stdin",
+     "name": "stdout",
     "output_type": "stream",
     "text": [
      "User (q/Q to quit):  how about shakira?\n"
@@ -446,7 +664,7 @@
     ]
    },
    {
-     "name": "stdin",
+     "name": "stdout",
     "output_type": "stream",
     "text": [
      "User (q/Q to quit):  hm cool\n"
@@ -483,7 +701,7 @@
     ]
    },
    {
-     "name": "stdin",
+     "name": "stdout",
     "output_type": "stream",
     "text": [
      "User (q/Q to quit):  q\n"
@@ -497,7 +715,27 @@
     ]
    }
   ],
-   "source": ["import uuid\n\nfrom langchain_core.messages import HumanMessage\n\nfrom langgraph.graph.graph import START\n\nhistory = []\nwhile True:\n    user = input(\"User (q/Q to quit): \")\n    if user in {\"q\", \"Q\"}:\n        print(\"AI: Byebye\")\n        break\n    history.append(HumanMessage(content=user))\n    async for output in graph.astream(history):\n        for key, value in output.items():\n            print(f\"Output from node '{key}':\")\n            print(\"---\")\n            print(value)\n        print(\"\\n---\\n\")"]
+   "source": [
+    "import uuid\n",
+    "\n",
+    "from langchain_core.messages import HumanMessage\n",
+    "\n",
+    "from langgraph.graph.graph import START\n",
+    "\n",
+    "history = []\n",
+    "while True:\n",
+    "    user = input(\"User (q/Q to quit): \")\n",
+    "    if user in {\"q\", \"Q\"}:\n",
+    "        print(\"AI: Byebye\")\n",
+    "        break\n",
+    "    history.append(HumanMessage(content=user))\n",
+    "    async for output in graph.astream(history):\n",
+    "        for key, value in output.items():\n",
+    "            print(f\"Output from node '{key}':\")\n",
+    "            print(\"---\")\n",
+    "            print(value)\n",
+    "        print(\"\\n---\\n\")"
+   ]
  }
 ],
 "metadata": {
@@ -176,10 +176,10 @@
   "metadata": {},
   "outputs": [],
   "source": [
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import START, MessageGraph\n",
    "\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "workflow = MessageGraph()\n",
    "workflow.add_node(\"info\", chain)\n",
    "workflow.add_node(\"prompt\", prompt_gen_chain)\n",
@@ -154,7 +154,7 @@
   "id": "2dff2209-44c7-4e2c-b607-ba6675f9e45f",
   "metadata": {},
   "outputs": [],
-   "source": ["from langgraph.checkpoint.sqlite import SqliteSaver\nfrom langgraph.graph import END, StateGraph, START\n\nbuilder = StateGraph(GraphState)\n\n# Define the nodes\nbuilder.add_node(\"generate\", generate)  # generation solution\nbuilder.add_node(\"check_code\", code_check)  # check code\n\n# Build graph\nbuilder.add_edge(START, \"generate\")\nbuilder.add_edge(\"generate\", \"check_code\")\nbuilder.add_conditional_edges(\n    \"check_code\",\n    decide_to_finish,\n    {\n        \"end\": END,\n        \"generate\": \"generate\",\n    },\n)\n\nmemory = SqliteSaver.from_conn_string(\":memory:\")\ngraph = builder.compile(checkpointer=memory)"]
+   "source": ["from langgraph.checkpoint.memory import MemorySaver\nfrom langgraph.graph import END, StateGraph, START\n\nbuilder = StateGraph(GraphState)\n\n# Define the nodes\nbuilder.add_node(\"generate\", generate)  # generation solution\nbuilder.add_node(\"check_code\", code_check)  # check code\n\n# Build graph\nbuilder.add_edge(START, \"generate\")\nbuilder.add_edge(\"generate\", \"check_code\")\nbuilder.add_conditional_edges(\n    \"check_code\",\n    decide_to_finish,\n    {\n        \"end\": END,\n        \"generate\": \"generate\",\n    },\n)\n\nmemory = MemorySaver()\ngraph = builder.compile(checkpointer=memory)"]
  },
  {
   "cell_type": "code",
@@ -1,247 +1,247 @@
 {
- "cells": [
-  {
-   "cell_type": "markdown",
-   "id": "992c4695-ec4f-428d-bd05-fb3b5fbd70f4",
-   "metadata": {},
-   "source": [
-    "# How to add human-in-the-loop processes to the prebuilt ReAct agent\n",
-    "\n",
-    "This tutorial will show how to add human-in-the-loop processes to the prebuilt ReAct agent. Please see [this tutorial](./create-react-agent.ipynb) for how to get started with the prebuilt ReAct agent\n",
-    "\n",
-    "You can add a a breakpoint before tools are called by passing `interrupt_before=[\"tools\"]` to `create_react_agent`. Note that you need to be using a checkpointer for this to work."
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "id": "7be3889f-3c17-4fa1-bd2b-84114a2c7247",
-   "metadata": {},
-   "source": [
-    "## Setup"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 1,
-   "id": "a213e11a-5c62-4ddb-a707-490d91add383",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "%%capture --no-stderr\n",
-    "%pip install -U langgraph langchain-openai"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 2,
-   "id": "23a1885c-04ab-4750-aefa-105891fddf3e",
-   "metadata": {},
-   "outputs": [
+  "cells": [
    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "OPENAI_API_KEY:  ········\n"
-     ]
-    }
-   ],
-   "source": [
-    "import getpass\n",
-    "import os\n",
-    "\n",
-    "\n",
-    "def _set_env(var: str):\n",
-    "    if not os.environ.get(var):\n",
-    "        os.environ[var] = getpass.getpass(f\"{var}: \")\n",
-    "\n",
-    "\n",
-    "_set_env(\"OPENAI_API_KEY\")\n",
-    "\n",
-    "# Recommended\n",
-    "_set_env(\"LANGCHAIN_API_KEY\")\n",
-    "os.environ[\"LANGCHAIN_TRACING_V2\"] = \"true\"\n",
-    "os.environ[\"LANGCHAIN_PROJECT\"] = \"Create ReAct Agent Tutorial\""
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "id": "03c0f089-070c-4cd4-87e0-6c51f2477b82",
-   "metadata": {},
-   "source": [
-    "## Code"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 3,
-   "id": "7a154152-973e-4b5d-aa13-48c617744a4c",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "# First we initialize the model we want to use.\n",
-    "from langchain_openai import ChatOpenAI\n",
-    "\n",
-    "model = ChatOpenAI(model=\"gpt-4o\", temperature=0)\n",
-    "\n",
-    "\n",
-    "# For this tutorial we will use custom tool that returns pre-defined values for weather in two cities (NYC & SF)\n",
-    "\n",
-    "from typing import Literal\n",
-    "\n",
-    "from langchain_core.tools import tool\n",
-    "\n",
-    "\n",
-    "@tool\n",
-    "def get_weather(city: Literal[\"nyc\", \"sf\"]):\n",
-    "    \"\"\"Use this to get weather information.\"\"\"\n",
-    "    if city == \"nyc\":\n",
-    "        return \"It might be cloudy in nyc\"\n",
-    "    elif city == \"sf\":\n",
-    "        return \"It's always sunny in sf\"\n",
-    "    else:\n",
-    "        raise AssertionError(\"Unknown city\")\n",
-    "\n",
-    "\n",
-    "tools = [get_weather]\n",
-    "\n",
-    "# We need a checkpointer to enable human-in-the-loop patterns\n",
-    "from langgraph.checkpoint import MemorySaver\n",
-    "\n",
-    "memory = MemorySaver()\n",
-    "\n",
-    "# Define the graph\n",
-    "\n",
-    "from langgraph.prebuilt import create_react_agent\n",
-    "\n",
-    "graph = create_react_agent(\n",
-    "    model, tools=tools, interrupt_before=[\"tools\"], checkpointer=memory\n",
-    ")"
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "id": "00407425-506d-4ffd-9c86-987921d8c844",
-   "metadata": {},
-   "source": [
-    "## Usage\n"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 2,
-   "id": "16636975-5f2d-4dc7-ab8e-d0bea0830a28",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "def print_stream(stream):\n",
-    "    for s in stream:\n",
-    "        message = s[\"messages\"][-1]\n",
-    "        if isinstance(message, tuple):\n",
-    "            print(message)\n",
-    "        else:\n",
-    "            message.pretty_print()"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 4,
-   "id": "9ffff6c3-a4f5-47c9-b51d-97caaee85cd6",
-   "metadata": {},
-   "outputs": [
+      "cell_type": "markdown",
+      "id": "992c4695-ec4f-428d-bd05-fb3b5fbd70f4",
+      "metadata": {},
+      "source": [
+        "# How to add human-in-the-loop processes to the prebuilt ReAct agent\n",
+        "\n",
+        "This tutorial will show how to add human-in-the-loop processes to the prebuilt ReAct agent. Please see [this tutorial](./create-react-agent.ipynb) for how to get started with the prebuilt ReAct agent\n",
+        "\n",
+        "You can add a a breakpoint before tools are called by passing `interrupt_before=[\"tools\"]` to `create_react_agent`. Note that you need to be using a checkpointer for this to work."
+      ]
+    },
    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "================================\u001b[1m Human Message \u001b[0m=================================\n",
-      "\n",
-      "What's the weather in SF?\n",
-      "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
-      "Tool Calls:\n",
-      "  get_weather (call_0OMmuTLec9t8kxMVkllZCSxo)\n",
-      " Call ID: call_0OMmuTLec9t8kxMVkllZCSxo\n",
-      "  Args:\n",
-      "    city: sf\n"
-     ]
-    }
-   ],
-   "source": [
-    "config = {\"configurable\": {\"thread_id\": \"42\"}}\n",
-    "inputs = {\"messages\": [(\"user\", \"What's the weather in SF?\")]}\n",
-    "\n",
-    "print_stream(graph.stream(inputs, config, stream_mode=\"values\"))"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 5,
-   "id": "3decf001-7228-4ed5-8779-2b9ed98a74ea",
-   "metadata": {},
-   "outputs": [
+      "cell_type": "markdown",
+      "id": "7be3889f-3c17-4fa1-bd2b-84114a2c7247",
+      "metadata": {},
+      "source": [
+        "## Setup"
+      ]
+    },
    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "Next step:  ('tools',)\n"
-     ]
-    }
-   ],
-   "source": [
-    "snapshot = graph.get_state(config)\n",
-    "print(\"Next step: \", snapshot.next)"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 6,
-   "id": "83148e08-63e8-49e5-a08b-02dc907bed1d",
-   "metadata": {},
-   "outputs": [
+      "cell_type": "code",
+      "execution_count": 1,
+      "id": "a213e11a-5c62-4ddb-a707-490d91add383",
+      "metadata": {},
+      "outputs": [],
+      "source": [
+        "%%capture --no-stderr\n",
+        "%pip install -U langgraph langchain-openai"
+      ]
+    },
    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "=================================\u001b[1m Tool Message \u001b[0m=================================\n",
-      "Name: get_weather\n",
-      "\n",
-      "It's always sunny in sf\n",
-      "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
-      "\n",
-      "The weather in San Francisco is currently sunny.\n"
-     ]
+      "cell_type": "code",
+      "execution_count": 2,
+      "id": "23a1885c-04ab-4750-aefa-105891fddf3e",
+      "metadata": {},
+      "outputs": [
+        {
+          "name": "stdout",
+          "output_type": "stream",
+          "text": [
+            "OPENAI_API_KEY:  ········\n"
+          ]
+        }
+      ],
+      "source": [
+        "import getpass\n",
+        "import os\n",
+        "\n",
+        "\n",
+        "def _set_env(var: str):\n",
+        "    if not os.environ.get(var):\n",
+        "        os.environ[var] = getpass.getpass(f\"{var}: \")\n",
+        "\n",
+        "\n",
+        "_set_env(\"OPENAI_API_KEY\")\n",
+        "\n",
+        "# Recommended\n",
+        "_set_env(\"LANGCHAIN_API_KEY\")\n",
+        "os.environ[\"LANGCHAIN_TRACING_V2\"] = \"true\"\n",
+        "os.environ[\"LANGCHAIN_PROJECT\"] = \"Create ReAct Agent Tutorial\""
+      ]
+    },
+    {
+      "cell_type": "markdown",
+      "id": "03c0f089-070c-4cd4-87e0-6c51f2477b82",
+      "metadata": {},
+      "source": [
+        "## Code"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 3,
+      "id": "7a154152-973e-4b5d-aa13-48c617744a4c",
+      "metadata": {},
+      "outputs": [],
+      "source": [
+        "# First we initialize the model we want to use.\n",
+        "from langchain_openai import ChatOpenAI\n",
+        "\n",
+        "model = ChatOpenAI(model=\"gpt-4o\", temperature=0)\n",
+        "\n",
+        "\n",
+        "# For this tutorial we will use custom tool that returns pre-defined values for weather in two cities (NYC & SF)\n",
+        "\n",
+        "from typing import Literal\n",
+        "\n",
+        "from langchain_core.tools import tool\n",
+        "\n",
+        "\n",
+        "@tool\n",
+        "def get_weather(city: Literal[\"nyc\", \"sf\"]):\n",
+        "    \"\"\"Use this to get weather information.\"\"\"\n",
+        "    if city == \"nyc\":\n",
+        "        return \"It might be cloudy in nyc\"\n",
+        "    elif city == \"sf\":\n",
+        "        return \"It's always sunny in sf\"\n",
+        "    else:\n",
+        "        raise AssertionError(\"Unknown city\")\n",
+        "\n",
+        "\n",
+        "tools = [get_weather]\n",
+        "\n",
+        "# We need a checkpointer to enable human-in-the-loop patterns\n",
+        "from langgraph.checkpoint.memory import MemorySaver\n",
+        "\n",
+        "memory = MemorySaver()\n",
+        "\n",
+        "# Define the graph\n",
+        "\n",
+        "from langgraph.prebuilt import create_react_agent\n",
+        "\n",
+        "graph = create_react_agent(\n",
+        "    model, tools=tools, interrupt_before=[\"tools\"], checkpointer=memory\n",
+        ")"
+      ]
+    },
+    {
+      "cell_type": "markdown",
+      "id": "00407425-506d-4ffd-9c86-987921d8c844",
+      "metadata": {},
+      "source": [
+        "## Usage\n"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 2,
+      "id": "16636975-5f2d-4dc7-ab8e-d0bea0830a28",
+      "metadata": {},
+      "outputs": [],
+      "source": [
+        "def print_stream(stream):\n",
+        "    for s in stream:\n",
+        "        message = s[\"messages\"][-1]\n",
+        "        if isinstance(message, tuple):\n",
+        "            print(message)\n",
+        "        else:\n",
+        "            message.pretty_print()"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 4,
+      "id": "9ffff6c3-a4f5-47c9-b51d-97caaee85cd6",
+      "metadata": {},
+      "outputs": [
+        {
+          "name": "stdout",
+          "output_type": "stream",
+          "text": [
+            "================================\u001b[1m Human Message \u001b[0m=================================\n",
+            "\n",
+            "What's the weather in SF?\n",
+            "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
+            "Tool Calls:\n",
+            "  get_weather (call_0OMmuTLec9t8kxMVkllZCSxo)\n",
+            " Call ID: call_0OMmuTLec9t8kxMVkllZCSxo\n",
+            "  Args:\n",
+            "    city: sf\n"
+          ]
+        }
+      ],
+      "source": [
+        "config = {\"configurable\": {\"thread_id\": \"42\"}}\n",
+        "inputs = {\"messages\": [(\"user\", \"What's the weather in SF?\")]}\n",
+        "\n",
+        "print_stream(graph.stream(inputs, config, stream_mode=\"values\"))"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 5,
+      "id": "3decf001-7228-4ed5-8779-2b9ed98a74ea",
+      "metadata": {},
+      "outputs": [
+        {
+          "name": "stdout",
+          "output_type": "stream",
+          "text": [
+            "Next step:  ('tools',)\n"
+          ]
+        }
+      ],
+      "source": [
+        "snapshot = graph.get_state(config)\n",
+        "print(\"Next step: \", snapshot.next)"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 6,
+      "id": "83148e08-63e8-49e5-a08b-02dc907bed1d",
+      "metadata": {},
+      "outputs": [
+        {
+          "name": "stdout",
+          "output_type": "stream",
+          "text": [
+            "=================================\u001b[1m Tool Message \u001b[0m=================================\n",
+            "Name: get_weather\n",
+            "\n",
+            "It's always sunny in sf\n",
+            "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
+            "\n",
+            "The weather in San Francisco is currently sunny.\n"
+          ]
+        }
+      ],
+      "source": [
+        "print_stream(graph.stream(None, config, stream_mode=\"values\"))"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": null,
+      "id": "6f6f8965-b016-4e25-be63-31c00fc0a6de",
+      "metadata": {},
+      "outputs": [],
+      "source": []
+    }
+  ],
+  "metadata": {
+    "kernelspec": {
+      "display_name": "Python 3 (ipykernel)",
+      "language": "python",
+      "name": "python3"
+    },
+    "language_info": {
+      "codemirror_mode": {
+        "name": "ipython",
+        "version": 3
+      },
+      "file_extension": ".py",
+      "mimetype": "text/x-python",
+      "name": "python",
+      "nbconvert_exporter": "python",
+      "pygments_lexer": "ipython3",
+      "version": "3.11.1"
    }
-   ],
-   "source": [
-    "print_stream(graph.stream(None, config, stream_mode=\"values\"))"
-   ]
  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "6f6f8965-b016-4e25-be63-31c00fc0a6de",
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  }
- ],
- "metadata": {
-  "kernelspec": {
-   "display_name": "Python 3 (ipykernel)",
-   "language": "python",
-   "name": "python3"
-  },
-  "language_info": {
-   "codemirror_mode": {
-    "name": "ipython",
-    "version": 3
-   },
-   "file_extension": ".py",
-   "mimetype": "text/x-python",
-   "name": "python",
-   "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython3",
-   "version": "3.11.1"
-  }
- },
- "nbformat": 4,
- "nbformat_minor": 5
+  "nbformat": 4,
+  "nbformat_minor": 5
 }
@@ -1,255 +1,255 @@
 {
- "cells": [
-  {
-   "cell_type": "markdown",
-   "id": "992c4695-ec4f-428d-bd05-fb3b5fbd70f4",
-   "metadata": {},
-   "source": [
-    "# How to add memory to the prebuilt ReAct agent\n",
-    "\n",
-    "This tutorial will show how to add memory to the prebuilt ReAct agent. Please see [this tutorial](./create-react-agent.ipynb) for how to get started with the prebuilt ReAct agent\n",
-    "\n",
-    "All we need to do to enable memory is pass in a checkpointer to `create_react_agents`"
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "id": "7be3889f-3c17-4fa1-bd2b-84114a2c7247",
-   "metadata": {},
-   "source": [
-    "## Setup"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 1,
-   "id": "a213e11a-5c62-4ddb-a707-490d91add383",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "%%capture --no-stderr\n",
-    "%pip install -U langgraph langchain-openai"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 2,
-   "id": "23a1885c-04ab-4750-aefa-105891fddf3e",
-   "metadata": {},
-   "outputs": [
+  "cells": [
    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "OPENAI_API_KEY:  ········\n"
-     ]
-    }
-   ],
-   "source": [
-    "import getpass\n",
-    "import os\n",
-    "\n",
-    "\n",
-    "def _set_env(var: str):\n",
-    "    if not os.environ.get(var):\n",
-    "        os.environ[var] = getpass.getpass(f\"{var}: \")\n",
-    "\n",
-    "\n",
-    "_set_env(\"OPENAI_API_KEY\")\n",
-    "\n",
-    "# Recommended\n",
-    "_set_env(\"LANGCHAIN_API_KEY\")\n",
-    "os.environ[\"LANGCHAIN_TRACING_V2\"] = \"true\"\n",
-    "os.environ[\"LANGCHAIN_PROJECT\"] = \"Create ReAct Agent Tutorial\""
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "id": "03c0f089-070c-4cd4-87e0-6c51f2477b82",
-   "metadata": {},
-   "source": [
-    "## Code"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 3,
-   "id": "7a154152-973e-4b5d-aa13-48c617744a4c",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "# First we initialize the model we want to use.\n",
-    "from langchain_openai import ChatOpenAI\n",
-    "\n",
-    "model = ChatOpenAI(model=\"gpt-4o\", temperature=0)\n",
-    "\n",
-    "\n",
-    "# For this tutorial we will use custom tool that returns pre-defined values for weather in two cities (NYC & SF)\n",
-    "\n",
-    "from typing import Literal\n",
-    "\n",
-    "from langchain_core.tools import tool\n",
-    "\n",
-    "\n",
-    "@tool\n",
-    "def get_weather(city: Literal[\"nyc\", \"sf\"]):\n",
-    "    \"\"\"Use this to get weather information.\"\"\"\n",
-    "    if city == \"nyc\":\n",
-    "        return \"It might be cloudy in nyc\"\n",
-    "    elif city == \"sf\":\n",
-    "        return \"It's always sunny in sf\"\n",
-    "    else:\n",
-    "        raise AssertionError(\"Unknown city\")\n",
-    "\n",
-    "\n",
-    "tools = [get_weather]\n",
-    "\n",
-    "# We can add \"chat memory\" to the graph with LangGraph's checkpointer\n",
-    "# to retain the chat context between interactions\n",
-    "from langgraph.checkpoint import MemorySaver\n",
-    "\n",
-    "memory = MemorySaver()\n",
-    "\n",
-    "# Define the graph\n",
-    "\n",
-    "from langgraph.prebuilt import create_react_agent\n",
-    "\n",
-    "graph = create_react_agent(model, tools=tools, checkpointer=memory)"
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "id": "00407425-506d-4ffd-9c86-987921d8c844",
-   "metadata": {},
-   "source": [
-    "## Usage\n",
-    "\n",
-    "Let's interact with it multiple times to show that it can remember"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 4,
-   "id": "16636975-5f2d-4dc7-ab8e-d0bea0830a28",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "def print_stream(stream):\n",
-    "    for s in stream:\n",
-    "        message = s[\"messages\"][-1]\n",
-    "        if isinstance(message, tuple):\n",
-    "            print(message)\n",
-    "        else:\n",
-    "            message.pretty_print()"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 5,
-   "id": "9ffff6c3-a4f5-47c9-b51d-97caaee85cd6",
-   "metadata": {},
-   "outputs": [
+      "cell_type": "markdown",
+      "id": "992c4695-ec4f-428d-bd05-fb3b5fbd70f4",
+      "metadata": {},
+      "source": [
+        "# How to add memory to the prebuilt ReAct agent\n",
+        "\n",
+        "This tutorial will show how to add memory to the prebuilt ReAct agent. Please see [this tutorial](./create-react-agent.ipynb) for how to get started with the prebuilt ReAct agent\n",
+        "\n",
+        "All we need to do to enable memory is pass in a checkpointer to `create_react_agents`"
+      ]
+    },
    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "================================\u001b[1m Human Message \u001b[0m=================================\n",
-      "\n",
-      "What's the weather in NYC?\n",
-      "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
-      "Tool Calls:\n",
-      "  get_weather (call_mdovy4yXSSYrmSlnlVSUacVn)\n",
-      " Call ID: call_mdovy4yXSSYrmSlnlVSUacVn\n",
-      "  Args:\n",
-      "    city: nyc\n",
-      "=================================\u001b[1m Tool Message \u001b[0m=================================\n",
-      "Name: get_weather\n",
-      "\n",
-      "It might be cloudy in nyc\n",
-      "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
-      "\n",
-      "The weather in NYC might be cloudy.\n"
-     ]
-    }
-   ],
-   "source": [
-    "config = {\"configurable\": {\"thread_id\": \"1\"}}\n",
-    "inputs = {\"messages\": [(\"user\", \"What's the weather in NYC?\")]}\n",
-    "\n",
-    "print_stream(graph.stream(inputs, config=config, stream_mode=\"values\"))"
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "id": "838a043f-90ad-4e69-9d1d-6e22db2c346c",
-   "metadata": {},
-   "source": [
-    "Notice that when we pass the same the same thread ID, the chat history is preserved"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": 6,
-   "id": "187479f9-32fa-4611-9487-cf816ba2e147",
-   "metadata": {},
-   "outputs": [
+      "cell_type": "markdown",
+      "id": "7be3889f-3c17-4fa1-bd2b-84114a2c7247",
+      "metadata": {},
+      "source": [
+        "## Setup"
+      ]
+    },
    {
-     "name": "stdout",
-     "output_type": "stream",
-     "text": [
-      "================================\u001b[1m Human Message \u001b[0m=================================\n",
-      "\n",
-      "What's it known for?\n",
-      "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
-      "\n",
-      "New York City (NYC) is known for many things, including:\n",
-      "\n",
-      "1. **Landmarks and Attractions**: The Statue of Liberty, Times Square, Central Park, Empire State Building, and Brooklyn Bridge.\n",
-      "2. **Cultural Institutions**: Broadway theaters, Metropolitan Museum of Art, Museum of Modern Art (MoMA), and the American Museum of Natural History.\n",
-      "3. **Diverse Neighborhoods**: Areas like Chinatown, Little Italy, Harlem, and Greenwich Village.\n",
-      "4. **Financial Hub**: Wall Street and the New York Stock Exchange.\n",
-      "5. **Cuisine**: A melting pot of global cuisines, famous for its pizza, bagels, and street food.\n",
-      "6. **Media and Entertainment**: Home to major media companies, TV networks, and film studios.\n",
-      "7. **Fashion**: A global fashion capital, hosting New York Fashion Week.\n",
-      "8. **Sports**: Teams like the New York Yankees, New York Mets, New York Knicks, and New York Rangers.\n",
-      "9. **Public Transportation**: An extensive subway system and iconic yellow taxis.\n",
-      "10. **Events**: New Year's Eve celebration in Times Square, Macy's Thanksgiving Day Parade, and various cultural festivals.\n"
-     ]
+      "cell_type": "code",
+      "execution_count": 1,
+      "id": "a213e11a-5c62-4ddb-a707-490d91add383",
+      "metadata": {},
+      "outputs": [],
+      "source": [
+        "%%capture --no-stderr\n",
+        "%pip install -U langgraph langchain-openai"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 2,
+      "id": "23a1885c-04ab-4750-aefa-105891fddf3e",
+      "metadata": {},
+      "outputs": [
+        {
+          "name": "stdout",
+          "output_type": "stream",
+          "text": [
+            "OPENAI_API_KEY:  ········\n"
+          ]
+        }
+      ],
+      "source": [
+        "import getpass\n",
+        "import os\n",
+        "\n",
+        "\n",
+        "def _set_env(var: str):\n",
+        "    if not os.environ.get(var):\n",
+        "        os.environ[var] = getpass.getpass(f\"{var}: \")\n",
+        "\n",
+        "\n",
+        "_set_env(\"OPENAI_API_KEY\")\n",
+        "\n",
+        "# Recommended\n",
+        "_set_env(\"LANGCHAIN_API_KEY\")\n",
+        "os.environ[\"LANGCHAIN_TRACING_V2\"] = \"true\"\n",
+        "os.environ[\"LANGCHAIN_PROJECT\"] = \"Create ReAct Agent Tutorial\""
+      ]
+    },
+    {
+      "cell_type": "markdown",
+      "id": "03c0f089-070c-4cd4-87e0-6c51f2477b82",
+      "metadata": {},
+      "source": [
+        "## Code"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 3,
+      "id": "7a154152-973e-4b5d-aa13-48c617744a4c",
+      "metadata": {},
+      "outputs": [],
+      "source": [
+        "# First we initialize the model we want to use.\n",
+        "from langchain_openai import ChatOpenAI\n",
+        "\n",
+        "model = ChatOpenAI(model=\"gpt-4o\", temperature=0)\n",
+        "\n",
+        "\n",
+        "# For this tutorial we will use custom tool that returns pre-defined values for weather in two cities (NYC & SF)\n",
+        "\n",
+        "from typing import Literal\n",
+        "\n",
+        "from langchain_core.tools import tool\n",
+        "\n",
+        "\n",
+        "@tool\n",
+        "def get_weather(city: Literal[\"nyc\", \"sf\"]):\n",
+        "    \"\"\"Use this to get weather information.\"\"\"\n",
+        "    if city == \"nyc\":\n",
+        "        return \"It might be cloudy in nyc\"\n",
+        "    elif city == \"sf\":\n",
+        "        return \"It's always sunny in sf\"\n",
+        "    else:\n",
+        "        raise AssertionError(\"Unknown city\")\n",
+        "\n",
+        "\n",
+        "tools = [get_weather]\n",
+        "\n",
+        "# We can add \"chat memory\" to the graph with LangGraph's checkpointer\n",
+        "# to retain the chat context between interactions\n",
+        "from langgraph.checkpoint.memory import MemorySaver\n",
+        "\n",
+        "memory = MemorySaver()\n",
+        "\n",
+        "# Define the graph\n",
+        "\n",
+        "from langgraph.prebuilt import create_react_agent\n",
+        "\n",
+        "graph = create_react_agent(model, tools=tools, checkpointer=memory)"
+      ]
+    },
+    {
+      "cell_type": "markdown",
+      "id": "00407425-506d-4ffd-9c86-987921d8c844",
+      "metadata": {},
+      "source": [
+        "## Usage\n",
+        "\n",
+        "Let's interact with it multiple times to show that it can remember"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 4,
+      "id": "16636975-5f2d-4dc7-ab8e-d0bea0830a28",
+      "metadata": {},
+      "outputs": [],
+      "source": [
+        "def print_stream(stream):\n",
+        "    for s in stream:\n",
+        "        message = s[\"messages\"][-1]\n",
+        "        if isinstance(message, tuple):\n",
+        "            print(message)\n",
+        "        else:\n",
+        "            message.pretty_print()"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 5,
+      "id": "9ffff6c3-a4f5-47c9-b51d-97caaee85cd6",
+      "metadata": {},
+      "outputs": [
+        {
+          "name": "stdout",
+          "output_type": "stream",
+          "text": [
+            "================================\u001b[1m Human Message \u001b[0m=================================\n",
+            "\n",
+            "What's the weather in NYC?\n",
+            "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
+            "Tool Calls:\n",
+            "  get_weather (call_mdovy4yXSSYrmSlnlVSUacVn)\n",
+            " Call ID: call_mdovy4yXSSYrmSlnlVSUacVn\n",
+            "  Args:\n",
+            "    city: nyc\n",
+            "=================================\u001b[1m Tool Message \u001b[0m=================================\n",
+            "Name: get_weather\n",
+            "\n",
+            "It might be cloudy in nyc\n",
+            "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
+            "\n",
+            "The weather in NYC might be cloudy.\n"
+          ]
+        }
+      ],
+      "source": [
+        "config = {\"configurable\": {\"thread_id\": \"1\"}}\n",
+        "inputs = {\"messages\": [(\"user\", \"What's the weather in NYC?\")]}\n",
+        "\n",
+        "print_stream(graph.stream(inputs, config=config, stream_mode=\"values\"))"
+      ]
+    },
+    {
+      "cell_type": "markdown",
+      "id": "838a043f-90ad-4e69-9d1d-6e22db2c346c",
+      "metadata": {},
+      "source": [
+        "Notice that when we pass the same the same thread ID, the chat history is preserved"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": 6,
+      "id": "187479f9-32fa-4611-9487-cf816ba2e147",
+      "metadata": {},
+      "outputs": [
+        {
+          "name": "stdout",
+          "output_type": "stream",
+          "text": [
+            "================================\u001b[1m Human Message \u001b[0m=================================\n",
+            "\n",
+            "What's it known for?\n",
+            "==================================\u001b[1m Ai Message \u001b[0m==================================\n",
+            "\n",
+            "New York City (NYC) is known for many things, including:\n",
+            "\n",
+            "1. **Landmarks and Attractions**: The Statue of Liberty, Times Square, Central Park, Empire State Building, and Brooklyn Bridge.\n",
+            "2. **Cultural Institutions**: Broadway theaters, Metropolitan Museum of Art, Museum of Modern Art (MoMA), and the American Museum of Natural History.\n",
+            "3. **Diverse Neighborhoods**: Areas like Chinatown, Little Italy, Harlem, and Greenwich Village.\n",
+            "4. **Financial Hub**: Wall Street and the New York Stock Exchange.\n",
+            "5. **Cuisine**: A melting pot of global cuisines, famous for its pizza, bagels, and street food.\n",
+            "6. **Media and Entertainment**: Home to major media companies, TV networks, and film studios.\n",
+            "7. **Fashion**: A global fashion capital, hosting New York Fashion Week.\n",
+            "8. **Sports**: Teams like the New York Yankees, New York Mets, New York Knicks, and New York Rangers.\n",
+            "9. **Public Transportation**: An extensive subway system and iconic yellow taxis.\n",
+            "10. **Events**: New Year's Eve celebration in Times Square, Macy's Thanksgiving Day Parade, and various cultural festivals.\n"
+          ]
+        }
+      ],
+      "source": [
+        "inputs = {\"messages\": [(\"user\", \"What's it known for?\")]}\n",
+        "print_stream(graph.stream(inputs, config=config, stream_mode=\"values\"))"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": null,
+      "id": "3decf001-7228-4ed5-8779-2b9ed98a74ea",
+      "metadata": {},
+      "outputs": [],
+      "source": []
+    }
+  ],
+  "metadata": {
+    "kernelspec": {
+      "display_name": "Python 3 (ipykernel)",
+      "language": "python",
+      "name": "python3"
+    },
+    "language_info": {
+      "codemirror_mode": {
+        "name": "ipython",
+        "version": 3
+      },
+      "file_extension": ".py",
+      "mimetype": "text/x-python",
+      "name": "python",
+      "nbconvert_exporter": "python",
+      "pygments_lexer": "ipython3",
+      "version": "3.11.1"
    }
-   ],
-   "source": [
-    "inputs = {\"messages\": [(\"user\", \"What's it known for?\")]}\n",
-    "print_stream(graph.stream(inputs, config=config, stream_mode=\"values\"))"
-   ]
  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "3decf001-7228-4ed5-8779-2b9ed98a74ea",
-   "metadata": {},
-   "outputs": [],
-   "source": []
-  }
- ],
- "metadata": {
-  "kernelspec": {
-   "display_name": "Python 3 (ipykernel)",
-   "language": "python",
-   "name": "python3"
-  },
-  "language_info": {
-   "codemirror_mode": {
-    "name": "ipython",
-    "version": 3
-   },
-   "file_extension": ".py",
-   "mimetype": "text/x-python",
-   "name": "python",
-   "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython3",
-   "version": "3.11.1"
-  }
- },
- "nbformat": 4,
- "nbformat_minor": 5
+  "nbformat": 4,
+  "nbformat_minor": 5
 }
@@ -39,7 +39,10 @@
   "id": "af4ce0ba-7596-4e5f-8bf8-0b0bd6e62833",
   "metadata": {},
   "outputs": [],
-   "source": ["%%capture --no-stderr\n%pip install --quiet -U langgraph langchain_openai"]
+   "source": [
+    "%%capture --no-stderr\n",
+    "%pip install --quiet -U langgraph langchain_openai"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -55,7 +58,18 @@
   "id": "c903a1cf-2977-4e2d-ad7d-8b3946821d89",
   "metadata": {},
   "outputs": [],
-   "source": ["import getpass\nimport os\n\n\ndef _set_env(var: str):\n    if not os.environ.get(var):\n        os.environ[var] = getpass.getpass(f\"{var}: \")\n\n\n_set_env(\"OPENAI_API_KEY\")"]
+   "source": [
+    "import getpass\n",
+    "import os\n",
+    "\n",
+    "\n",
+    "def _set_env(var: str):\n",
+    "    if not os.environ.get(var):\n",
+    "        os.environ[var] = getpass.getpass(f\"{var}: \")\n",
+    "\n",
+    "\n",
+    "_set_env(\"OPENAI_API_KEY\")"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -71,7 +85,10 @@
   "id": "95e25aec-7c9f-4a63-b143-225d0e9a79c3",
   "metadata": {},
   "outputs": [],
-   "source": ["os.environ[\"LANGCHAIN_TRACING_V2\"] = \"true\"\n_set_env(\"LANGCHAIN_API_KEY\")"]
+   "source": [
+    "os.environ[\"LANGCHAIN_TRACING_V2\"] = \"true\"\n",
+    "_set_env(\"LANGCHAIN_API_KEY\")"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -89,7 +106,22 @@
   "id": "6098e5cb",
   "metadata": {},
   "outputs": [],
-   "source": ["from typing import Annotated\n\nfrom typing_extensions import TypedDict\n\nfrom langgraph.graph.message import add_messages\n\n# `add_messages`` essentially does this\n# (with more robust handling)\n# def add_messages(left: list, right: list):\n#     return left + right\n\n\nclass State(TypedDict):\n    messages: Annotated[list, add_messages]"]
+   "source": [
+    "from typing import Annotated\n",
+    "\n",
+    "from typing_extensions import TypedDict\n",
+    "\n",
+    "from langgraph.graph.message import add_messages\n",
+    "\n",
+    "# `add_messages`` essentially does this\n",
+    "# (with more robust handling)\n",
+    "# def add_messages(left: list, right: list):\n",
+    "#     return left + right\n",
+    "\n",
+    "\n",
+    "class State(TypedDict):\n",
+    "    messages: Annotated[list, add_messages]"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -109,7 +141,22 @@
   "id": "d7ef57dd-5d6e-4ad3-9377-a92201c1310e",
   "metadata": {},
   "outputs": [],
-   "source": ["from langchain_core.tools import tool\n\n\n@tool\ndef search(query: str):\n    \"\"\"Call to surf the web.\"\"\"\n    # This is a placeholder for the actual implementation\n    # Don't let the LLM know this though 😊\n    return [\n        \"It's sunny in San Francisco, but you better look out if you're a Gemini 😈.\"\n    ]\n\n\ntools = [search]"]
+   "source": [
+    "from langchain_core.tools import tool\n",
+    "\n",
+    "\n",
+    "@tool\n",
+    "def search(query: str):\n",
+    "    \"\"\"Call to surf the web.\"\"\"\n",
+    "    # This is a placeholder for the actual implementation\n",
+    "    # Don't let the LLM know this though 😊\n",
+    "    return [\n",
+    "        \"It's sunny in San Francisco, but you better look out if you're a Gemini 😈.\"\n",
+    "    ]\n",
+    "\n",
+    "\n",
+    "tools = [search]"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -127,7 +174,11 @@
   "id": "5cf3331e-ccb3-41c8-aeb9-a840a94d41e7",
   "metadata": {},
   "outputs": [],
-   "source": ["from langgraph.prebuilt import ToolExecutor\n\ntool_executor = ToolExecutor(tools)"]
+   "source": [
+    "from langgraph.prebuilt import ToolExecutor\n",
+    "\n",
+    "tool_executor = ToolExecutor(tools)"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -148,7 +199,11 @@
   "id": "892b54b9-75f0-4804-9ed0-88b5e5532989",
   "metadata": {},
   "outputs": [],
-   "source": ["from langchain_openai import ChatOpenAI\n\nmodel = ChatOpenAI(temperature=0)"]
+   "source": [
+    "from langchain_openai import ChatOpenAI\n",
+    "\n",
+    "model = ChatOpenAI(temperature=0)"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -166,7 +221,9 @@
   "id": "cd3cbae5-d92c-4559-a4aa-44721b80d107",
   "metadata": {},
   "outputs": [],
-   "source": ["model = model.bind_tools(tools)"]
+   "source": [
+    "model = model.bind_tools(tools)"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -201,7 +258,53 @@
   "id": "3b541bb9-900c-40d0-964d-7b5dfee30667",
   "metadata": {},
   "outputs": [],
-   "source": ["from langchain_core.messages import ToolMessage\n\nfrom langgraph.prebuilt import ToolInvocation\n\n\n# Define the function that determines whether to continue or not\ndef should_continue(state):\n    messages = state[\"messages\"]\n    last_message = messages[-1]\n    # If there is no function call, then we finish\n    if not last_message.tool_calls:\n        return \"end\"\n    # Otherwise if there is, we continue\n    else:\n        return \"continue\"\n\n\n# Define the function that calls the model\ndef call_model(state):\n    messages = state[\"messages\"]\n    response = model.invoke(messages)\n    # We return a list, because this will get added to the existing list\n    return {\"messages\": [response]}\n\n\n# Define the function to execute tools\ndef call_tool(state):\n    messages = state[\"messages\"]\n    # Based on the continue condition\n    # we know the last message involves a function call\n    last_message = messages[-1]\n    # We construct an ToolInvocation from the function_call\n    tool_call = last_message.tool_calls[0]\n    action = ToolInvocation(\n        tool=tool_call[\"name\"],\n        tool_input=tool_call[\"args\"],\n    )\n    # We call the tool_executor and get back a response\n    response = tool_executor.invoke(action)\n    # We use the response to create a ToolMessage\n    tool_message = ToolMessage(\n        content=str(response), name=action.tool, tool_call_id=tool_call[\"id\"]\n    )\n    # We return a list, because this will get added to the existing list\n    return {\"messages\": [tool_message]}"]
+   "source": [
+    "from langchain_core.messages import ToolMessage\n",
+    "\n",
+    "from langgraph.prebuilt import ToolInvocation\n",
+    "\n",
+    "\n",
+    "# Define the function that determines whether to continue or not\n",
+    "def should_continue(state):\n",
+    "    messages = state[\"messages\"]\n",
+    "    last_message = messages[-1]\n",
+    "    # If there is no function call, then we finish\n",
+    "    if not last_message.tool_calls:\n",
+    "        return \"end\"\n",
+    "    # Otherwise if there is, we continue\n",
+    "    else:\n",
+    "        return \"continue\"\n",
+    "\n",
+    "\n",
+    "# Define the function that calls the model\n",
+    "def call_model(state):\n",
+    "    messages = state[\"messages\"]\n",
+    "    response = model.invoke(messages)\n",
+    "    # We return a list, because this will get added to the existing list\n",
+    "    return {\"messages\": [response]}\n",
+    "\n",
+    "\n",
+    "# Define the function to execute tools\n",
+    "def call_tool(state):\n",
+    "    messages = state[\"messages\"]\n",
+    "    # Based on the continue condition\n",
+    "    # we know the last message involves a function call\n",
+    "    last_message = messages[-1]\n",
+    "    # We construct an ToolInvocation from the function_call\n",
+    "    tool_call = last_message.tool_calls[0]\n",
+    "    action = ToolInvocation(\n",
+    "        tool=tool_call[\"name\"],\n",
+    "        tool_input=tool_call[\"args\"],\n",
+    "    )\n",
+    "    # We call the tool_executor and get back a response\n",
+    "    response = tool_executor.invoke(action)\n",
+    "    # We use the response to create a ToolMessage\n",
+    "    tool_message = ToolMessage(\n",
+    "        content=str(response), name=action.tool, tool_call_id=tool_call[\"id\"]\n",
+    "    )\n",
+    "    # We return a list, because this will get added to the existing list\n",
+    "    return {\"messages\": [tool_message]}"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -219,7 +322,45 @@
   "id": "812b4e70-4956-4415-8880-db48b3dcbad2",
   "metadata": {},
   "outputs": [],
-   "source": ["from langgraph.graph import END, StateGraph, START\n\n# Define a new graph\nworkflow = StateGraph(State)\n\n# Define the two nodes we will cycle between\nworkflow.add_node(\"agent\", call_model)\nworkflow.add_node(\"action\", call_tool)\n\n# Set the entrypoint as `agent`\n# This means that this node is the first one called\nworkflow.add_edge(START, \"agent\")\n\n# We now add a conditional edge\nworkflow.add_conditional_edges(\n    # First, we define the start node. We use `agent`.\n    # This means these are the edges taken after the `agent` node is called.\n    \"agent\",\n    # Next, we pass in the function that will determine which node is called next.\n    should_continue,\n    # Finally we pass in a mapping.\n    # The keys are strings, and the values are other nodes.\n    # END is a special node marking that the graph should finish.\n    # What will happen is we will call `should_continue`, and then the output of that\n    # will be matched against the keys in this mapping.\n    # Based on which one it matches, that node will then be called.\n    {\n        # If `tools`, then we call the tool node.\n        \"continue\": \"action\",\n        # Otherwise we finish.\n        \"end\": END,\n    },\n)\n\n# We now add a normal edge from `tools` to `agent`.\n# This means that after `tools` is called, `agent` node is called next.\nworkflow.add_edge(\"action\", \"agent\")"]
+   "source": [
+    "from langgraph.graph import END, StateGraph, START\n",
+    "\n",
+    "# Define a new graph\n",
+    "workflow = StateGraph(State)\n",
+    "\n",
+    "# Define the two nodes we will cycle between\n",
+    "workflow.add_node(\"agent\", call_model)\n",
+    "workflow.add_node(\"action\", call_tool)\n",
+    "\n",
+    "# Set the entrypoint as `agent`\n",
+    "# This means that this node is the first one called\n",
+    "workflow.add_edge(START, \"agent\")\n",
+    "\n",
+    "# We now add a conditional edge\n",
+    "workflow.add_conditional_edges(\n",
+    "    # First, we define the start node. We use `agent`.\n",
+    "    # This means these are the edges taken after the `agent` node is called.\n",
+    "    \"agent\",\n",
+    "    # Next, we pass in the function that will determine which node is called next.\n",
+    "    should_continue,\n",
+    "    # Finally we pass in a mapping.\n",
+    "    # The keys are strings, and the values are other nodes.\n",
+    "    # END is a special node marking that the graph should finish.\n",
+    "    # What will happen is we will call `should_continue`, and then the output of that\n",
+    "    # will be matched against the keys in this mapping.\n",
+    "    # Based on which one it matches, that node will then be called.\n",
+    "    {\n",
+    "        # If `tools`, then we call the tool node.\n",
+    "        \"continue\": \"action\",\n",
+    "        # Otherwise we finish.\n",
+    "        \"end\": END,\n",
+    "    },\n",
+    ")\n",
+    "\n",
+    "# We now add a normal edge from `tools` to `agent`.\n",
+    "# This means that after `tools` is called, `agent` node is called next.\n",
+    "workflow.add_edge(\"action\", \"agent\")"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -237,7 +378,11 @@
   "id": "6845ed6a-d155-4105-9160-28849877248b",
   "metadata": {},
   "outputs": [],
-   "source": ["from langgraph.checkpoint.sqlite import SqliteSaver\n\nmemory = SqliteSaver.from_conn_string(\":memory:\")"]
+   "source": [
+    "from langgraph.checkpoint.memory import MemorySaver\n",
+    "\n",
+    "memory = MemorySaver()"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -255,7 +400,12 @@
   "id": "79d29875-8aa8-434c-9f20-1c58346a6249",
   "metadata": {},
   "outputs": [],
-   "source": ["# Finally, we compile it!\n# This compiles it into a LangChain Runnable,\n# meaning you can use it as you would any other runnable\napp = workflow.compile(checkpointer=memory, interrupt_before=[\"action\"])"]
+   "source": [
+    "# Finally, we compile it!\n",
+    "# This compiles it into a LangChain Runnable,\n",
+    "# meaning you can use it as you would any other runnable\n",
+    "app = workflow.compile(checkpointer=memory, interrupt_before=[\"action\"])"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -282,7 +432,11 @@
     "output_type": "display_data"
    }
   ],
-   "source": ["from IPython.display import Image, display\n\ndisplay(Image(app.get_graph().draw_mermaid_png()))"]
+   "source": [
+    "from IPython.display import Image, display\n",
+    "\n",
+    "display(Image(app.get_graph().draw_mermaid_png()))"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -313,7 +467,14 @@
     ]
    }
   ],
-   "source": ["from langchain_core.messages import HumanMessage\n\nthread = {\"configurable\": {\"thread_id\": \"2\"}}\ninputs = [HumanMessage(content=\"hi! I'm bob\")]\nfor event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n    event[\"messages\"][-1].pretty_print()"]
+   "source": [
+    "from langchain_core.messages import HumanMessage\n",
+    "\n",
+    "thread = {\"configurable\": {\"thread_id\": \"2\"}}\n",
+    "inputs = [HumanMessage(content=\"hi! I'm bob\")]\n",
+    "for event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n",
+    "    event[\"messages\"][-1].pretty_print()"
+   ]
  },
  {
   "cell_type": "code",
@@ -334,7 +495,11 @@
     ]
    }
   ],
-   "source": ["inputs = [HumanMessage(content=\"What did I tell you my name was?\")]\nfor event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n    event[\"messages\"][-1].pretty_print()"]
+   "source": [
+    "inputs = [HumanMessage(content=\"What did I tell you my name was?\")]\n",
+    "for event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n",
+    "    event[\"messages\"][-1].pretty_print()"
+   ]
  },
  {
   "cell_type": "code",
@@ -358,7 +523,11 @@
     ]
    }
   ],
-   "source": ["inputs = [HumanMessage(content=\"what's the weather in sf now?\")]\nfor event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n    event[\"messages\"][-1].pretty_print()"]
+   "source": [
+    "inputs = [HumanMessage(content=\"what's the weather in sf now?\")]\n",
+    "for event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n",
+    "    event[\"messages\"][-1].pretty_print()"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -392,7 +561,10 @@
     ]
    }
   ],
-   "source": ["for event in app.stream(None, thread, stream_mode=\"values\"):\n    event[\"messages\"][-1].pretty_print()"]
+   "source": [
+    "for event in app.stream(None, thread, stream_mode=\"values\"):\n",
+    "    event[\"messages\"][-1].pretty_print()"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -427,7 +599,43 @@
   "id": "5454f436-d56e-4499-9381-06192aca1b56",
   "metadata": {},
   "outputs": [],
-   "source": ["import json\nfrom typing import Optional\n\nfrom langchain_core.messages import AIMessage\n\n\n# Helper function to construct message asking for verification\ndef generate_verification_message(message: AIMessage) -> None:\n    \"\"\"Generate \"verification message\" from message with tool calls.\"\"\"\n    serialized_tool_calls = json.dumps(\n        message.tool_calls,\n        indent=2,\n    )\n    return AIMessage(\n        content=(\n            \"I plan to invoke the following tools, do you approve?\\n\\n\"\n            \"Type 'y' if you do, anything else to stop.\\n\\n\"\n            f\"{serialized_tool_calls}\"\n        ),\n        id=message.id,\n    )\n\n\n# Helper function to stream output from the graph\ndef stream_app_catch_tool_calls(inputs, thread) -> Optional[AIMessage]:\n    \"\"\"Stream app, catching tool calls.\"\"\"\n    tool_call_message = None\n    for event in app.stream(inputs, thread, stream_mode=\"values\"):\n        message = event[\"messages\"][-1]\n        if isinstance(message, AIMessage) and message.tool_calls:\n            tool_call_message = message\n        else:\n            message.pretty_print()\n\n    return tool_call_message"]
+   "source": [
+    "import json\n",
+    "from typing import Optional\n",
+    "\n",
+    "from langchain_core.messages import AIMessage\n",
+    "\n",
+    "\n",
+    "# Helper function to construct message asking for verification\n",
+    "def generate_verification_message(message: AIMessage) -> None:\n",
+    "    \"\"\"Generate \"verification message\" from message with tool calls.\"\"\"\n",
+    "    serialized_tool_calls = json.dumps(\n",
+    "        message.tool_calls,\n",
+    "        indent=2,\n",
+    "    )\n",
+    "    return AIMessage(\n",
+    "        content=(\n",
+    "            \"I plan to invoke the following tools, do you approve?\\n\\n\"\n",
+    "            \"Type 'y' if you do, anything else to stop.\\n\\n\"\n",
+    "            f\"{serialized_tool_calls}\"\n",
+    "        ),\n",
+    "        id=message.id,\n",
+    "    )\n",
+    "\n",
+    "\n",
+    "# Helper function to stream output from the graph\n",
+    "def stream_app_catch_tool_calls(inputs, thread) -> Optional[AIMessage]:\n",
+    "    \"\"\"Stream app, catching tool calls.\"\"\"\n",
+    "    tool_call_message = None\n",
+    "    for event in app.stream(inputs, thread, stream_mode=\"values\"):\n",
+    "        message = event[\"messages\"][-1]\n",
+    "        if isinstance(message, AIMessage) and message.tool_calls:\n",
+    "            tool_call_message = message\n",
+    "        else:\n",
+    "            message.pretty_print()\n",
+    "\n",
+    "    return tool_call_message"
+   ]
  },
  {
   "cell_type": "code",
@@ -514,7 +722,43 @@
     ]
    }
   ],
-   "source": ["import uuid\n\nthread = {\"configurable\": {\"thread_id\": \"3\"}}\n\ntool_call_message = stream_app_catch_tool_calls(\n    {\"messages\": [HumanMessage(\"what's the weather in sf now?\")]},\n    thread,\n)\n\nwhile tool_call_message:\n    verification_message = generate_verification_message(tool_call_message)\n    verification_message.pretty_print()\n    input_message = HumanMessage(input())\n    if input_message.content == \"exit\":\n        break\n    input_message.pretty_print()\n\n    # First we update the state with the verification message and the input message.\n    # note that `generate_verification_message` sets the message ID to be the same\n    # as the ID from the original tool call message. Updating the state with this\n    # message will overwrite the previous tool call.\n    snapshot = app.get_state(thread)\n    snapshot.values[\"messages\"] += [verification_message, input_message]\n\n    if input_message.content == \"y\":\n        tool_call_message.id = str(uuid.uuid4())\n        # If verified, we append the tool call message to the state\n        # and resume execution.\n        snapshot.values[\"messages\"] += [tool_call_message]\n        app.update_state(thread, snapshot.values, as_node=\"agent\")\n    else:\n        # Otherwise, resume execution from the input message.\n        app.update_state(thread, snapshot.values, as_node=\"__start__\")\n\n    tool_call_message = stream_app_catch_tool_calls(None, thread)"]
+   "source": [
+    "import uuid\n",
+    "\n",
+    "thread = {\"configurable\": {\"thread_id\": \"3\"}}\n",
+    "\n",
+    "tool_call_message = stream_app_catch_tool_calls(\n",
+    "    {\"messages\": [HumanMessage(\"what's the weather in sf now?\")]},\n",
+    "    thread,\n",
+    ")\n",
+    "\n",
+    "while tool_call_message:\n",
+    "    verification_message = generate_verification_message(tool_call_message)\n",
+    "    verification_message.pretty_print()\n",
+    "    input_message = HumanMessage(input())\n",
+    "    if input_message.content == \"exit\":\n",
+    "        break\n",
+    "    input_message.pretty_print()\n",
+    "\n",
+    "    # First we update the state with the verification message and the input message.\n",
+    "    # note that `generate_verification_message` sets the message ID to be the same\n",
+    "    # as the ID from the original tool call message. Updating the state with this\n",
+    "    # message will overwrite the previous tool call.\n",
+    "    snapshot = app.get_state(thread)\n",
+    "    snapshot.values[\"messages\"] += [verification_message, input_message]\n",
+    "\n",
+    "    if input_message.content == \"y\":\n",
+    "        tool_call_message.id = str(uuid.uuid4())\n",
+    "        # If verified, we append the tool call message to the state\n",
+    "        # and resume execution.\n",
+    "        snapshot.values[\"messages\"] += [tool_call_message]\n",
+    "        app.update_state(thread, snapshot.values, as_node=\"agent\")\n",
+    "    else:\n",
+    "        # Otherwise, resume execution from the input message.\n",
+    "        app.update_state(thread, snapshot.values, as_node=\"__start__\")\n",
+    "\n",
+    "    tool_call_message = stream_app_catch_tool_calls(None, thread)"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -535,7 +779,34 @@
   "id": "03232f16-d6fe-46d0-afa0-a6f0d0bf16de",
   "metadata": {},
   "outputs": [],
-   "source": ["class State(TypedDict):\n    messages: Annotated[list, add_messages]\n    tool_call_message: Optional[AIMessage]\n\n\ndef call_model(state):\n    messages = state[\"messages\"]\n    if messages[-1].content == \"y\":\n        return {\n            \"messages\": [state[\"tool_call_message\"]],\n            \"tool_call_message\": None,\n        }\n    else:\n        response = model.invoke(messages)\n        if response.tool_calls:\n            verification_message = generate_verification_message(response)\n            response.id = str(uuid.uuid4())\n            return {\n                \"messages\": [verification_message],\n                \"tool_call_message\": response,\n            }\n        else:\n            return {\n                \"messages\": [response],\n                \"tool_call_message\": None,\n            }"]
+   "source": [
+    "class State(TypedDict):\n",
+    "    messages: Annotated[list, add_messages]\n",
+    "    tool_call_message: Optional[AIMessage]\n",
+    "\n",
+    "\n",
+    "def call_model(state):\n",
+    "    messages = state[\"messages\"]\n",
+    "    if messages[-1].content == \"y\":\n",
+    "        return {\n",
+    "            \"messages\": [state[\"tool_call_message\"]],\n",
+    "            \"tool_call_message\": None,\n",
+    "        }\n",
+    "    else:\n",
+    "        response = model.invoke(messages)\n",
+    "        if response.tool_calls:\n",
+    "            verification_message = generate_verification_message(response)\n",
+    "            response.id = str(uuid.uuid4())\n",
+    "            return {\n",
+    "                \"messages\": [verification_message],\n",
+    "                \"tool_call_message\": response,\n",
+    "            }\n",
+    "        else:\n",
+    "            return {\n",
+    "                \"messages\": [response],\n",
+    "                \"tool_call_message\": None,\n",
+    "            }"
+   ]
  },
  {
   "cell_type": "markdown",
@@ -551,7 +822,27 @@
   "id": "502dc688-c926-407e-8759-8c9e39eb4257",
   "metadata": {},
   "outputs": [],
-   "source": ["workflow = StateGraph(State)\n\nworkflow.add_node(\"agent\", call_model)\nworkflow.add_node(\"action\", call_tool)\n\nworkflow.add_edge(START, \"agent\")\n\nworkflow.add_conditional_edges(\n    \"agent\",\n    should_continue,\n    {\n        \"continue\": \"action\",\n        \"end\": END,\n    },\n)\n\nworkflow.add_edge(\"action\", \"agent\")\n\napp = workflow.compile(checkpointer=memory)"]
+   "source": [
+    "workflow = StateGraph(State)\n",
+    "\n",
+    "workflow.add_node(\"agent\", call_model)\n",
+    "workflow.add_node(\"action\", call_tool)\n",
+    "\n",
+    "workflow.add_edge(START, \"agent\")\n",
+    "\n",
+    "workflow.add_conditional_edges(\n",
+    "    \"agent\",\n",
+    "    should_continue,\n",
+    "    {\n",
+    "        \"continue\": \"action\",\n",
+    "        \"end\": END,\n",
+    "    },\n",
+    ")\n",
+    "\n",
+    "workflow.add_edge(\"action\", \"agent\")\n",
+    "\n",
+    "app = workflow.compile(checkpointer=memory)"
+   ]
  },
  {
   "cell_type": "code",
@@ -584,7 +875,13 @@
     ]
    }
   ],
-   "source": ["thread = {\"configurable\": {\"thread_id\": \"4\"}}\n\ninputs = [HumanMessage(content=\"what's the weather in sf?\")]\nfor event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n    event[\"messages\"][-1].pretty_print()"]
+   "source": [
+    "thread = {\"configurable\": {\"thread_id\": \"4\"}}\n",
+    "\n",
+    "inputs = [HumanMessage(content=\"what's the weather in sf?\")]\n",
+    "for event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n",
+    "    event[\"messages\"][-1].pretty_print()"
+   ]
  },
  {
   "cell_type": "code",
@@ -617,7 +914,11 @@
     ]
    }
   ],
-   "source": ["inputs = [HumanMessage(content=\"can you specify sf in CA?\")]\nfor event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n    event[\"messages\"][-1].pretty_print()"]
+   "source": [
+    "inputs = [HumanMessage(content=\"can you specify sf in CA?\")]\n",
+    "for event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n",
+    "    event[\"messages\"][-1].pretty_print()"
+   ]
  },
  {
   "cell_type": "code",
@@ -648,7 +949,11 @@
     ]
    }
   ],
-   "source": ["inputs = [HumanMessage(content=\"y\")]\nfor event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n    event[\"messages\"][-1].pretty_print()"]
+   "source": [
+    "inputs = [HumanMessage(content=\"y\")]\n",
+    "for event in app.stream({\"messages\": inputs}, thread, stream_mode=\"values\"):\n",
+    "    event[\"messages\"][-1].pretty_print()"
+   ]
  }
 ],
 "metadata": {
@@ -42,7 +42,6 @@
    "def answer_node(state: InputState):\n",
    "    return {\"answer\": \"bye\"}\n",
    "\n",
-    "check = SqliteSaver.from_conn_string(\":memory:\")\n",
    "graph = StateGraph(input=InputState, output=OutputState)\n",
    "graph.add_node(answer_node)\n",
    "graph.add_edge(START, \"answer_node\")\n",
@@ -84,8 +84,9 @@
   ]
  },
  {
+   "attachments": {},
   "cell_type": "markdown",
-   "id": "ef7bcad1-1274-4b7c-a2e9-365180ef3a31",
+   "id": "9c374e41-f9b7-439e-a520-6d8c853c5220",
   "metadata": {},
   "source": [
    "## Part 1: Build a Basic Chatbot\n",
@@ -120,13 +121,24 @@
    "graph_builder = StateGraph(State)"
   ]
  },
+  {
+   "cell_type": "markdown",
+   "id": "31c755cd-8994-4867-bdff-96a55d7beae7",
+   "metadata": {},
+   "source": [
+    "<div class=\"admonition tip\">\n",
+    "    <p class=\"admonition-title\">Note</p>\n",
+    "    <p>\n",
+    "    The first thing you do when you define a graph is define the <code>State</code> of the graph. The <code>State</code> consists of the schema of the graph as well as reducer functions which specify how to apply updates to the state. In our example <code>State</code> is a <code>TypedDict</code> with a single key: <code>messages</code>. The <code>messages</code> key is annotated with the <a href=\"https://langchain-ai.github.io/langgraph/reference/graphs/?h=add+messages#add_messages\"><code>add_messages</code></a> reducer function, which tells LangGraph to append new messages to the existing list, rather than overwriting it. State keys without an annotation will be overwritten by each update, storing the most recent value. Check out <a href=\"https://langchain-ai.github.io/langgraph/reference/graphs/?h=add+messages#add_messages\">this conceptual guide</a> to learn more about state, reducers and other low-level concepts.\n",
+    "    </p>\n",
+    "</div>"
+   ]
+  },
  {
   "cell_type": "markdown",
   "id": "4137feed-746e-4c72-a34a-f7a699ad5dcf",
   "metadata": {},
   "source": [
-    "**Notice** that we've defined our `State` as a TypedDict with a single key: `messages`. The `messages` key is annotated with the [`add_messages`](https://langchain-ai.github.io/langgraph/reference/graphs/?h=add+messages#add_messages) function, which tells LangGraph to append new messages to the existing list, rather than overwriting it.\n",
-    "\n",
    "So now our graph knows two things:\n",
    "\n",
    "1. Every `node` we define will receive the current `State` as input and return a value that updates that state.\n",
@@ -836,7 +848,7 @@
    "\n",
    "We will see later that **checkpointing** is _much_ more powerful than simple chat memory - it lets you save and resume complex state at any time for error recovery, human-in-the-loop workflows, time travel interactions, and more. But before we get too ahead of ourselves, let's add checkpointing to enable multi-turn conversations.\n",
    "\n",
-    "To get started, create a `SqliteSaver` checkpointer."
+    "To get started, create a `MemorySaver` checkpointer."
   ]
  },
  {
@@ -846,9 +858,9 @@
   "metadata": {},
   "outputs": [],
   "source": [
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")"
+    "memory = MemorySaver()"
   ]
  },
  {
@@ -856,7 +868,7 @@
   "id": "08d3d11a-1b42-4cbb-8e11-2a4294263d90",
   "metadata": {},
   "source": [
-    "**Notice** that we've specified `:memory` as the Sqlite DB path. This is convenient for our tutorial (it saves it all in-memory). In a production application, you would likely change this to connect to your own DB and/or use one of the other checkpointer classes.\n",
+    "**Notice** we're using an in-memory checkpointer. This is convenient for our tutorial (it saves it all in-memory). In a production application, you would likely change this to use `SqliteSaver` or `PostgresSaver` and connect to your own DB.\n",
    "\n",
    "Next define the graph. Now that you've already built your own `BasicToolNode`, we'll replace it with LangGraph's prebuilt `ToolNode` and `tools_condition`, since these do some nice things like parallel API execution. Apart from that, the following is all copied from Part 2."
   ]
@@ -1187,7 +1199,7 @@
    "from langchain_core.messages import BaseMessage\n",
    "from typing_extensions import TypedDict\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import StateGraph\n",
    "from langgraph.graph.message import add_messages\n",
    "from langgraph.prebuilt import ToolNode\n",
@@ -1265,12 +1277,12 @@
    "from langchain_core.messages import BaseMessage\n",
    "from typing_extensions import TypedDict\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import StateGraph, START\n",
    "from langgraph.graph.message import add_messages\n",
    "from langgraph.prebuilt import ToolNode, tools_condition\n",
    "\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "\n",
    "\n",
    "class State(TypedDict):\n",
@@ -1496,7 +1508,7 @@
    "from langchain_core.messages import BaseMessage\n",
    "from typing_extensions import TypedDict\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import StateGraph\n",
    "from langgraph.graph.message import add_messages\n",
    "from langgraph.prebuilt import ToolNode\n",
@@ -1531,7 +1543,7 @@
    "graph_builder.add_edge(\"tools\", \"chatbot\")\n",
    "graph_builder.set_entry_point(\"chatbot\")\n",
    "\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "graph = graph_builder.compile(\n",
    "    checkpointer=memory,\n",
    "    # This is new!\n",
@@ -1581,7 +1593,7 @@
    "from langchain_core.messages import BaseMessage\n",
    "from typing_extensions import TypedDict\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import StateGraph, START\n",
    "from langgraph.graph.message import add_messages\n",
    "from langgraph.prebuilt import ToolNode, tools_condition\n",
@@ -1615,7 +1627,7 @@
    ")\n",
    "graph_builder.add_edge(\"tools\", \"chatbot\")\n",
    "graph_builder.add_edge(START, \"chatbot\")\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "graph = graph_builder.compile(\n",
    "    checkpointer=memory,\n",
    "    # This is new!\n",
@@ -2080,7 +2092,7 @@
    "from langchain_core.messages import BaseMessage\n",
    "from typing_extensions import TypedDict\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import StateGraph, START\n",
    "from langgraph.graph.message import add_messages\n",
    "from langgraph.prebuilt import ToolNode, tools_condition\n",
@@ -2277,7 +2289,7 @@
    "graph_builder.add_edge(\"tools\", \"chatbot\")\n",
    "graph_builder.add_edge(\"human\", \"chatbot\")\n",
    "graph_builder.add_edge(START, \"chatbot\")\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "graph = graph_builder.compile(\n",
    "    checkpointer=memory,\n",
    "    # We interrupt before 'human' here instead.\n",
@@ -2527,7 +2539,7 @@
    "from langchain_core.pydantic_v1 import BaseModel\n",
    "from typing_extensions import TypedDict\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import StateGraph\n",
    "from langgraph.graph.message import add_messages\n",
    "from langgraph.prebuilt import ToolNode, tools_condition\n",
@@ -2614,7 +2626,7 @@
    "graph_builder.add_edge(\"tools\", \"chatbot\")\n",
    "graph_builder.add_edge(\"human\", \"chatbot\")\n",
    "graph_builder.set_entry_point(\"chatbot\")\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "graph = graph_builder.compile(\n",
    "    checkpointer=memory,\n",
    "    interrupt_before=[\"human\"],\n",
@@ -2653,11 +2665,11 @@
    "\n",
    "from langchain_anthropic import ChatAnthropic\n",
    "from langchain_community.tools.tavily_search import TavilySearchResults\n",
-    "from langchain_core.messages import AIMessage, BaseMessage, ToolMessage\n",
+    "from langchain_core.messages import AIMessage, ToolMessage\n",
    "from langchain_core.pydantic_v1 import BaseModel\n",
    "from typing_extensions import TypedDict\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import StateGraph, START\n",
    "from langgraph.graph.message import add_messages\n",
    "from langgraph.prebuilt import ToolNode, tools_condition\n",
@@ -2744,7 +2756,7 @@
    "graph_builder.add_edge(\"tools\", \"chatbot\")\n",
    "graph_builder.add_edge(\"human\", \"chatbot\")\n",
    "graph_builder.add_edge(START, \"chatbot\")\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "graph = graph_builder.compile(\n",
    "    checkpointer=memory,\n",
    "    interrupt_before=[\"human\"],\n",
@@ -3056,9 +3068,9 @@
 ],
 "metadata": {
  "kernelspec": {
-   "display_name": "Python 3 (ipykernel)",
+   "display_name": "langgraph",
   "language": "python",
-   "name": "python3"
+   "name": "langgraph"
  },
  "language_info": {
   "codemirror_mode": {
@@ -3070,7 +3082,7 @@
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
-   "version": "3.11.1"
+   "version": "3.11.9"
  }
 },
 "nbformat": 4,
@@ -105,10 +105,10 @@
    "\n",
    "from langchain_anthropic import ChatAnthropic\n",
    "from langchain_core.messages import SystemMessage, RemoveMessage\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import MessagesState, StateGraph, START, END\n",
    "\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "\n",
    "\n",
    "# We will add a `summary` attribute (in addition to `messages` key,\n",
@@ -112,11 +112,11 @@
    "from langchain_anthropic import ChatAnthropic\n",
    "from langchain_core.tools import tool\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import MessagesState, StateGraph, START\n",
    "from langgraph.prebuilt import ToolNode\n",
    "\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "\n",
    "\n",
    "@tool\n",
@@ -103,11 +103,11 @@
    "from langchain_anthropic import ChatAnthropic\n",
    "from langchain_core.tools import tool\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import MessagesState, StateGraph, START\n",
    "from langgraph.prebuilt import ToolNode\n",
    "\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "\n",
    "\n",
    "@tool\n",
@@ -234,11 +234,11 @@
    "from langchain_anthropic import ChatAnthropic\n",
    "from langchain_core.tools import tool\n",
    "\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import MessagesState, StateGraph, START\n",
    "from langgraph.prebuilt import ToolNode\n",
    "\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "\n",
    "\n",
    "@tool\n",
@@ -8,7 +8,7 @@
    "\n",
    "There are many use cases where you may wish for your node to have a custom retry policy, for example if you are calling an API, querying a database, or calling an LLM, etc. \n",
    "\n",
-    "In order to configure the retry policty, you have to pass the `retry` parameter to the `add_node` function. The `retry` parameter takes in a `RetryPolicy` named tuple object. Below we instantiate a `RetryPolicy` object with the default parameters:"
+    "In order to configure the retry policy, you have to pass the `retry` parameter to the `add_node` function. The `retry` parameter takes in a `RetryPolicy` named tuple object. Below we instantiate a `RetryPolicy` object with the default parameters:"
   ]
  },
  {
@@ -7,7 +7,7 @@
   "source": [
    "# How to pass private state\n",
    "\n",
-    "Oftentimes, you may want nodes to be able to pass state to eachv other that should NOT be part of the main schema of the graph. This is often useful because there may be information that is not needed as input/output (and therefore doesn't really make sense to have in the main schema) but is ABSOLUTELY needed as part of the intermediate working logic.\n",
+    "Oftentimes, you may want nodes to be able to pass state to each other that should NOT be part of the main schema of the graph. This is often useful because there may be information that is not needed as input/output (and therefore doesn't really make sense to have in the main schema) but is ABSOLUTELY needed as part of the intermediate working logic.\n",
    "\n",
    "Let's take a look at an example below. In this example, we will create a RAG pipeline that:\n",
    "1. Takes in a user question\n",
@@ -246,7 +246,7 @@
   "id": "6845ed6a-d155-4105-9160-28849877248b",
   "metadata": {},
   "outputs": [],
-   "source": ["from langgraph.checkpoint.sqlite import SqliteSaver\n\nmemory = SqliteSaver.from_conn_string(\":memory:\")"]
+   "source": ["from langgraph.checkpoint.memory import MemorySaver\n\nmemory = MemorySaver()"]
  },
  {
   "cell_type": "code",
@@ -15,6 +15,7 @@
    "\n",
    "```\n",
    "ollama pull llama3-groq-tool-use\n",
+    "ollama pull llama3.1\n",
    "```\n",
    "\n",
    "And also, we'll use the Ollama partner package.\n",
@@ -39,35 +40,39 @@
  },
  {
   "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 6,
   "id": "120c1da8-e45e-4ffa-9ac1-a536026c7e1c",
   "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "\n",
+      "\u001b[1m[\u001b[0m\u001b[34;49mnotice\u001b[0m\u001b[1;39;49m]\u001b[0m\u001b[39;49m A new release of pip is available: \u001b[0m\u001b[31;49m24.0\u001b[0m\u001b[39;49m -> \u001b[0m\u001b[32;49m24.1.2\u001b[0m\n",
+      "\u001b[1m[\u001b[0m\u001b[34;49mnotice\u001b[0m\u001b[1;39;49m]\u001b[0m\u001b[39;49m To update, run: \u001b[0m\u001b[32;49mpip install --upgrade pip\u001b[0m\n",
+      "Note: you may need to restart the kernel to use updated packages.\n"
+     ]
+    }
+   ],
   "source": [
    "%pip install -qU langchain-ollama"
   ]
  },
  {
   "cell_type": "code",
-   "execution_count": 1,
+   "execution_count": 8,
   "id": "32c0504b-007a-4af6-9976-c7294ed26b73",
   "metadata": {},
-   "outputs": [
-    {
-     "name": "stderr",
-     "output_type": "stream",
-     "text": [
-      "USER_AGENT environment variable not set, consider setting it to identify your requests.\n"
-     ]
-    }
-   ],
+   "outputs": [],
   "source": [
    "# /// LLM ///\n",
    "\n",
    "from langchain_ollama import ChatOllama\n",
    "\n",
    "llm = ChatOllama(\n",
-    "    model=\"llama3-groq-tool-use\",\n",
+    "    # model=\"llama3-groq-tool-use\",\n",
+    "    model=\"llama3.1\",\n",
    "    temperature=0,\n",
    ")\n",
    "\n",
@@ -129,14 +134,13 @@
    "        for d in web_results\n",
    "    ]\n",
    "\n",
-    "\n",
    "# Tool list\n",
    "tools = [retrieve_documents, web_search]"
   ]
  },
  {
   "cell_type": "code",
-   "execution_count": 2,
+   "execution_count": 9,
   "id": "30052f47-2b5d-46f5-9873-eb716145cda1",
   "metadata": {},
   "outputs": [],
@@ -148,11 +152,9 @@
    "from langgraph.graph.message import AnyMessage, add_messages\n",
    "from typing_extensions import TypedDict\n",
    "\n",
-    "\n",
    "class State(TypedDict):\n",
    "    messages: Annotated[list[AnyMessage], add_messages]\n",
    "\n",
-    "\n",
    "class Assistant:\n",
    "    def __init__(self, runnable: Runnable):\n",
    "        \"\"\"\n",
@@ -209,7 +211,7 @@
  },
  {
   "cell_type": "code",
-   "execution_count": 3,
+   "execution_count": 10,
   "id": "40504a0b-8a99-4420-a6bf-561c62e893d1",
   "metadata": {},
   "outputs": [
@@ -251,7 +253,7 @@
    "\n",
    "\n",
    "from IPython.display import Image, display\n",
-    "from langgraph.checkpoint.sqlite import SqliteSaver\n",
+    "from langgraph.checkpoint.memory import MemorySaver\n",
    "from langgraph.graph import END, START, StateGraph\n",
    "from langgraph.prebuilt import tools_condition\n",
    "\n",
@@ -273,7 +275,7 @@
    "builder.add_edge(\"tools\", \"assistant\")\n",
    "\n",
    "# The checkpointer lets the graph persist its state\n",
-    "memory = SqliteSaver.from_conn_string(\":memory:\")\n",
+    "memory = MemorySaver()\n",
    "react_graph = builder.compile(checkpointer=memory)\n",
    "\n",
    "# Show\n",
@@ -282,7 +284,7 @@
  },
  {
   "cell_type": "code",
-   "execution_count": 4,
+   "execution_count": 11,
   "id": "43c633d5-e7a7-4b7c-8dc7-760a3b032e95",
   "metadata": {},
   "outputs": [],
@@ -301,9 +303,19 @@
    "response = predict_react_agent_answer(example)"
   ]
  },
+  {
+   "cell_type": "markdown",
+   "id": "bf82fa52-9e6c-4f37-94ae-91450dac602e",
+   "metadata": {},
+   "source": [
+    "See trace with llama3.1 here:\n",
+    "\n",
+    "https://smith.langchain.com/public/44d0c7dd-a756-47ad-8025-ee7ae6469ecb/r"
+   ]
+  },
  {
   "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 13,
   "id": "cd74a0b3-be40-46cd-97bf-ef9676878289",
   "metadata": {},
   "outputs": [],
@@ -311,6 +323,24 @@
    "example = {\"input\": \"Get me information about the current weather in SF.\"}\n",
    "response = predict_react_agent_answer(example)"
   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "8cac91bf-c975-44a2-a9fd-99706fee5735",
+   "metadata": {},
+   "source": [
+    "See trace with llama3.1 here:\n",
+    "\n",
+    "https://smith.langchain.com/public/7a4938e3-f94f-4e04-a162-bf592fba4643/r"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "74b813cb-18ed-42d8-b313-6ee56ded4bcc",
+   "metadata": {},
+   "outputs": [],
+   "source": []
  }
 ],
 "metadata": {
@@ -598,7 +598,7 @@
   "id": "e6e73e85-1232-4848-beba-3139ac7d0a64",
   "metadata": {},
   "outputs": [],
-   "source": ["from langgraph.checkpoint.sqlite import SqliteSaver\nfrom langgraph.graph import END, StateGraph, START\n\nbuilder = StateGraph(State)\nbuilder.add_node(\"draft\", draft_solver)\nbuilder.add_edge(START, \"draft\")\nbuilder.add_node(\"retrieve\", retrieve_examples)\nbuilder.add_node(\"solve\", solver)\nbuilder.add_node(\"evaluate\", evaluate)\n# Add connectivity\nbuilder.add_edge(\"draft\", \"retrieve\")\nbuilder.add_edge(\"retrieve\", \"solve\")\nbuilder.add_edge(\"solve\", \"evaluate\")\n\n\ndef control_edge(state: State):\n    if state.get(\"status\") == \"success\":\n        return END\n    return \"solve\"\n\n\nbuilder.add_conditional_edges(\"evaluate\", control_edge, {END: END, \"solve\": \"solve\"})\n\n\ncheckpointer = SqliteSaver.from_conn_string(\":memory:\")\ngraph = builder.compile(checkpointer=checkpointer)"]
+   "source": ["from langgraph.checkpoint.memory import MemorySaver\nfrom langgraph.graph import END, StateGraph, START\n\nbuilder = StateGraph(State)\nbuilder.add_node(\"draft\", draft_solver)\nbuilder.add_edge(START, \"draft\")\nbuilder.add_node(\"retrieve\", retrieve_examples)\nbuilder.add_node(\"solve\", solver)\nbuilder.add_node(\"evaluate\", evaluate)\n# Add connectivity\nbuilder.add_edge(\"draft\", \"retrieve\")\nbuilder.add_edge(\"retrieve\", \"solve\")\nbuilder.add_edge(\"solve\", \"evaluate\")\n\n\ndef control_edge(state: State):\n    if state.get(\"status\") == \"success\":\n        return END\n    return \"solve\"\n\n\nbuilder.add_conditional_edges(\"evaluate\", control_edge, {END: END, \"solve\": \"solve\"})\n\n\ncheckpointer = MemorySaver()\ngraph = builder.compile(checkpointer=checkpointer)"]
  },
  {
   "cell_type": "code",
@@ -809,7 +809,7 @@
   "id": "3c6456ba-363c-4133-8631-6dabb042b6ce",
   "metadata": {},
   "outputs": [],
-   "source": ["# This is all the same as before\nfrom langgraph.checkpoint.sqlite import SqliteSaver\nfrom langgraph.graph import END, StateGraph, START\n\nbuilder = StateGraph(State)\nprompt = hub.pull(\"wfh/usaco-draft-solver\")\nllm = ChatAnthropic(model=\"claude-3-opus-20240229\", max_tokens_to_sample=4000)\n\ndraft_solver = Solver(llm, prompt.partial(examples=\"\"))\nbuilder.add_node(\"draft\", draft_solver)\nbuilder.add_edge(START, \"draft\")\nbuilder.add_node(\"retrieve\", retrieve_examples)\nsolver = Solver(llm, prompt)\nbuilder.add_node(\"solve\", solver)\nbuilder.add_node(\"evaluate\", evaluate)\nbuilder.add_edge(\"draft\", \"retrieve\")\nbuilder.add_edge(\"retrieve\", \"solve\")\nbuilder.add_edge(\"solve\", \"evaluate\")\n\n\ndef control_edge(state: State):\n    if state.get(\"status\") == \"success\":\n        return END\n    return \"solve\"\n\n\nbuilder.add_conditional_edges(\"evaluate\", control_edge, {END: END, \"solve\": \"solve\"})\ncheckpointer = SqliteSaver.from_conn_string(\":memory:\")"]
+   "source": ["# This is all the same as before\nfrom langgraph.checkpoint.memory import MemorySaver\nfrom langgraph.graph import END, StateGraph, START\n\nbuilder = StateGraph(State)\nprompt = hub.pull(\"wfh/usaco-draft-solver\")\nllm = ChatAnthropic(model=\"claude-3-opus-20240229\", max_tokens_to_sample=4000)\n\ndraft_solver = Solver(llm, prompt.partial(examples=\"\"))\nbuilder.add_node(\"draft\", draft_solver)\nbuilder.add_edge(START, \"draft\")\nbuilder.add_node(\"retrieve\", retrieve_examples)\nsolver = Solver(llm, prompt)\nbuilder.add_node(\"solve\", solver)\nbuilder.add_node(\"evaluate\", evaluate)\nbuilder.add_edge(\"draft\", \"retrieve\")\nbuilder.add_edge(\"retrieve\", \"solve\")\nbuilder.add_edge(\"solve\", \"evaluate\")\n\n\ndef control_edge(state: State):\n    if state.get(\"status\") == \"success\":\n        return END\n    return \"solve\"\n\n\nbuilder.add_conditional_edges(\"evaluate\", control_edge, {END: END, \"solve\": \"solve\"})\ncheckpointer = MemorySaver()"]
  },
  {
   "cell_type": "markdown",
@@ -268,7 +268,7 @@
   ],
   "source": [
    "from IPython.display import Image, display\n",
-    "from langchain_core.runnables.graph import CurveStyle, MermaidDrawMethod, NodeColors\n",
+    "from langchain_core.runnables.graph import CurveStyle, MermaidDrawMethod, NodeStyles\n",
    "\n",
    "display(\n",
    "    Image(\n",
@@ -340,7 +340,7 @@
    "    Image(\n",
    "        app.get_graph().draw_mermaid_png(\n",
    "            curve_style=CurveStyle.LINEAR,\n",
-    "            node_colors=NodeColors(start=\"#ffdfba\", end=\"#baffc9\", other=\"#fad7de\"),\n",
+    "            node_colors=NodeStyles(first=\"#ffdfba\", last=\"#baffc9\", default=\"#fad7de\"),\n",
    "            wrap_label_n_words=9,\n",
    "            output_file_path=None,\n",
    "            draw_method=MermaidDrawMethod.PYPPETEER,\n",
@@ -0,0 +1,48 @@
+.PHONY: test test_watch lint format
+
+######################
+# TESTING AND COVERAGE
+######################
+
+start-postgres:
+	docker compose -f tests/compose-postgres.yml up -V --force-recreate --wait
+
+stop-postgres:
+	docker compose -f tests/compose-postgres.yml down
+
+test:
+	make start-postgres; \
+	poetry run pytest; \
+	EXIT_CODE=$$?; \
+	make stop-postgres; \
+	exit $$EXIT_CODE
+
+test_watch:
+	make start-postgres; \
+	poetry run ptw .; \
+	EXIT_CODE=$$?; \
+	make stop-postgres; \
+	exit $$EXIT_CODE
+
+######################
+# LINTING AND FORMATTING
+######################
+
+# Define a variable for Python and notebook files.
+PYTHON_FILES=.
+MYPY_CACHE=.mypy_cache
+lint format: PYTHON_FILES=.
+lint_diff format_diff: PYTHON_FILES=$(shell git diff --name-only --relative --diff-filter=d main . | grep -E '\.py$$|\.ipynb$$')
+lint_package: PYTHON_FILES=langgraph
+lint_tests: PYTHON_FILES=tests
+lint_tests: MYPY_CACHE=.mypy_cache_test
+
+lint lint_diff lint_package lint_tests:
+	poetry run ruff .
+	[ "$(PYTHON_FILES)" = "" ] || poetry run ruff format $(PYTHON_FILES) --diff
+	[ "$(PYTHON_FILES)" = "" ] || poetry run ruff --select I $(PYTHON_FILES)
+	[ "$(PYTHON_FILES)" = "" ] || mkdir -p $(MYPY_CACHE) || poetry run mypy $(PYTHON_FILES) --cache-dir $(MYPY_CACHE)
+
+format format_diff:
+	poetry run ruff format $(PYTHON_FILES)
+	poetry run ruff --select I --fix $(PYTHON_FILES)
@@ -0,0 +1,101 @@
+# LangGraph Checkpoint Postgres
+
+Implementation of LangGraph CheckpointSaver that uses Postgres.
+
+## Usage
+
+> [!IMPORTANT]
+> When using Postgres checkpointers for the first time, make sure to call `.setup()` method on them to create required tables. See example below.
+
+> [!IMPORTANT]
+> When manually creating Postgres connections and passing them to `PostgresSaver` or `AsyncPostgresSaver`, make sure to include `autocommit=True` and `row_factory=dict_row` (`from psycopg.rows import dict_row`). See a full example in this [how-to guide](https://langchain-ai.github.io/langgraph/how-tos/persistence_postgres/).
+
+```python
+from langgraph.checkpoint.postgres import PostgresSaver
+
+write_config = {"configurable": {"thread_id": "1", "checkpoint_ns": ""}}
+read_config = {"configurable": {"thread_id": "1"}}
+
+DB_URI = "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable"
+with PostgresSaver.from_conn_string(DB_URI) as checkpointer:
+    # call .setup() the first time you're using the checkpointer
+    checkpointer.setup()
+    checkpoint = {
+        "v": 1,
+        "ts": "2024-07-31T20:14:19.804150+00:00",
+        "id": "1ef4f797-8335-6428-8001-8a1503f9b875",
+        "channel_values": {
+            "my_key": "meow",
+            "node": "node"
+        },
+        "channel_versions": {
+            "__start__": 2,
+            "my_key": 3,
+            "start:node": 3,
+            "node": 3
+        },
+        "versions_seen": {
+            "__input__": {},
+            "__start__": {
+            "__start__": 1
+            },
+            "node": {
+            "start:node": 2
+            }
+        },
+        "pending_sends": [],
+        "current_tasks": {}
+    }
+
+    # store checkpoint
+    checkpointer.put(write_config, checkpoint, {}, {})
+
+    # load checkpoint
+    checkpointer.get(read_config)
+
+    # list checkpoints
+    list(checkpointer.list(read_config))
+```
+
+### Async
+
+```python
+from langgraph.checkpoint.postgres.aio import AsyncPostgresSaver
+
+async with AsyncPostgresSaver.from_conn_string(DB_URI) as checkpointer:
+    checkpoint = {
+        "v": 1,
+        "ts": "2024-07-31T20:14:19.804150+00:00",
+        "id": "1ef4f797-8335-6428-8001-8a1503f9b875",
+        "channel_values": {
+            "my_key": "meow",
+            "node": "node"
+        },
+        "channel_versions": {
+            "__start__": 2,
+            "my_key": 3,
+            "start:node": 3,
+            "node": 3
+        },
+        "versions_seen": {
+            "__input__": {},
+            "__start__": {
+            "__start__": 1
+            },
+            "node": {
+            "start:node": 2
+            }
+        },
+        "pending_sends": [],
+        "current_tasks": {}
+    }
+
+    # store checkpoint
+    await checkpointer.aput(write_config, checkpoint, {}, {})
+
+    # load checkpoint
+    await checkpointer.aget(read_config)
+
+    # list checkpoints
+    [c async for c in checkpointer.alist(read_config)]
+```
@@ -0,0 +1,350 @@
+import threading
+from contextlib import contextmanager
+from typing import Any, Iterator, List, Optional
+
+from langchain_core.runnables import RunnableConfig
+from psycopg import Connection, Cursor, Pipeline
+from psycopg.errors import UndefinedTable
+from psycopg.rows import dict_row
+from psycopg.types.json import Jsonb
+
+from langgraph.checkpoint.base import (
+    ChannelVersions,
+    Checkpoint,
+    CheckpointMetadata,
+    CheckpointTuple,
+    get_checkpoint_id,
+)
+from langgraph.checkpoint.postgres.base import (
+    BasePostgresSaver,
+)
+from langgraph.checkpoint.serde.base import SerializerProtocol
+
+
+class PostgresSaver(BasePostgresSaver):
+    lock: threading.Lock
+
+    def __init__(
+        self,
+        conn: Connection,
+        pipe: Optional[Pipeline] = None,
+        serde: Optional[SerializerProtocol] = None,
+    ) -> None:
+        super().__init__(serde=serde)
+        self.conn = conn
+        self.pipe = pipe
+        self.lock = threading.Lock()
+
+    @classmethod
+    @contextmanager
+    def from_conn_string(
+        cls, conn_string: str, *, pipeline: bool = False
+    ) -> Iterator["PostgresSaver"]:
+        """Create a new PostgresSaver instance from a connection string.
+
+        Args:
+            conn_string (str): The Postgres connection info string.
+            pipeline (bool): whether to use Pipeline
+
+        Returns:
+            PostgresSaver: A new PostgresSaver instance.
+        """
+        with Connection.connect(
+            conn_string, autocommit=True, prepare_threshold=0, row_factory=dict_row
+        ) as conn:
+            if pipeline:
+                with conn.pipeline() as pipe:
+                    yield PostgresSaver(conn, pipe)
+            else:
+                yield PostgresSaver(conn)
+
+    def setup(self) -> None:
+        """Set up the checkpoint database asynchronously.
+
+        This method creates the necessary tables in the Postgres database if they don't
+        already exist and runs database migrations. It MUST be called directly by the user
+        the first time checkpointer is used.
+        """
+        with self.lock:
+            with self.conn.cursor(binary=True) as cur:
+                try:
+                    version = cur.execute(
+                        "SELECT v FROM checkpoint_migrations ORDER BY v DESC LIMIT 1"
+                    ).fetchone()["v"]
+                except UndefinedTable:
+                    version = -1
+                for v, migration in zip(
+                    range(version + 1, len(self.MIGRATIONS)),
+                    self.MIGRATIONS[version + 1 :],
+                ):
+                    cur.execute(migration)
+                    cur.execute(f"INSERT INTO checkpoint_migrations (v) VALUES ({v})")
+            if self.pipe:
+                self.pipe.sync()
+
+    def list(
+        self,
+        config: Optional[RunnableConfig],
+        *,
+        filter: Optional[dict[str, Any]] = None,
+        before: Optional[RunnableConfig] = None,
+        limit: Optional[int] = None,
+    ) -> Iterator[CheckpointTuple]:
+        """List checkpoints from the database.
+
+        This method retrieves a list of checkpoint tuples from the Postgres database based
+        on the provided config. The checkpoints are ordered by checkpoint ID in descending order (newest first).
+
+        Args:
+            config (RunnableConfig): The config to use for listing the checkpoints.
+            filter (Optional[Dict[str, Any]]): Additional filtering criteria for metadata. Defaults to None.
+            before (Optional[RunnableConfig]): If provided, only checkpoints before the specified checkpoint ID are returned. Defaults to None.
+            limit (Optional[int]): The maximum number of checkpoints to return. Defaults to None.
+
+        Yields:
+            Iterator[CheckpointTuple]: An iterator of checkpoint tuples.
+
+        Examples:
+            >>> from langgraph.checkpoint.postgres import PostgresSaver
+            >>> DB_URI = "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable"
+            >>> with PostgresSaver.from_conn_string(DB_URI) as memory:
+            ... # Run a graph, then list the checkpoints
+            >>>     config = {"configurable": {"thread_id": "1"}}
+            >>>     checkpoints = list(memory.list(config, limit=2))
+            >>> print(checkpoints)
+            [CheckpointTuple(...), CheckpointTuple(...)]
+
+            >>> config = {"configurable": {"thread_id": "1"}}
+            >>> before = {"configurable": {"checkpoint_id": "1ef4f797-8335-6428-8001-8a1503f9b875"}}
+            >>> with PostgresSaver.from_conn_string(DB_URI) as memory:
+            ... # Run a graph, then list the checkpoints
+            >>>     checkpoints = list(memory.list(config, before=before))
+            >>> print(checkpoints)
+            [CheckpointTuple(...), ...]
+        """
+        where, args = self._search_where(config, filter, before)
+        query = self.SELECT_SQL + where + " ORDER BY checkpoint_id DESC"
+        if limit:
+            query += f" LIMIT {limit}"
+        # if we change this to use .stream() we need to make sure to close the cursor
+        for value in self.conn.execute(query, args, binary=True):
+            yield CheckpointTuple(
+                {
+                    "configurable": {
+                        "thread_id": value["thread_id"],
+                        "checkpoint_ns": value["checkpoint_ns"],
+                        "checkpoint_id": value["checkpoint_id"],
+                    }
+                },
+                {
+                    **self._load_checkpoint(value["checkpoint"]),
+                    "channel_values": self._load_blobs(value["channel_values"]),
+                },
+                self._load_metadata(value["metadata"]),
+                {
+                    "configurable": {
+                        "thread_id": value["thread_id"],
+                        "checkpoint_ns": value["checkpoint_ns"],
+                        "checkpoint_id": value["parent_checkpoint_id"],
+                    }
+                }
+                if value["parent_checkpoint_id"]
+                else None,
+            )
+
+    def get_tuple(self, config: RunnableConfig) -> Optional[CheckpointTuple]:
+        """Get a checkpoint tuple from the database.
+
+        This method retrieves a checkpoint tuple from the Postgres database based on the
+        provided config. If the config contains a "checkpoint_id" key, the checkpoint with
+        the matching thread ID and timestamp is retrieved. Otherwise, the latest checkpoint
+        for the given thread ID is retrieved.
+
+        Args:
+            config (RunnableConfig): The config to use for retrieving the checkpoint.
+
+        Returns:
+            Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.
+
+        Examples:
+
+            Basic:
+            >>> config = {"configurable": {"thread_id": "1"}}
+            >>> checkpoint_tuple = memory.get_tuple(config)
+            >>> print(checkpoint_tuple)
+            CheckpointTuple(...)
+
+            With timestamp:
+
+            >>> config = {
+            ...    "configurable": {
+            ...        "thread_id": "1",
+            ...        "checkpoint_ns": "",
+            ...        "checkpoint_id": "1ef4f797-8335-6428-8001-8a1503f9b875",
+            ...    }
+            ... }
+            >>> checkpoint_tuple = memory.get_tuple(config)
+            >>> print(checkpoint_tuple)
+            CheckpointTuple(...)
+        """  # noqa
+        thread_id = config["configurable"]["thread_id"]
+        checkpoint_id = get_checkpoint_id(config)
+        checkpoint_ns = config["configurable"].get("checkpoint_ns", "")
+        if checkpoint_id:
+            args = (thread_id, checkpoint_ns, checkpoint_id)
+            where = "WHERE thread_id = %s AND checkpoint_ns = %s AND checkpoint_id = %s"
+        else:
+            args = (thread_id, checkpoint_ns)
+            where = "WHERE thread_id = %s AND checkpoint_ns = %s ORDER BY checkpoint_id DESC LIMIT 1"
+
+        with self._cursor() as cur:
+            cur = self.conn.execute(
+                self.SELECT_SQL + where,
+                args,
+                binary=True,
+            )
+
+            for value in cur:
+                return CheckpointTuple(
+                    {
+                        "configurable": {
+                            "thread_id": thread_id,
+                            "checkpoint_ns": checkpoint_ns,
+                            "checkpoint_id": value["checkpoint_id"],
+                        }
+                    },
+                    {
+                        **self._load_checkpoint(value["checkpoint"]),
+                        "channel_values": self._load_blobs(value["channel_values"]),
+                    },
+                    self._load_metadata(value["metadata"]),
+                    {
+                        "configurable": {
+                            "thread_id": thread_id,
+                            "checkpoint_ns": checkpoint_ns,
+                            "checkpoint_id": value["parent_checkpoint_id"],
+                        }
+                    }
+                    if value["parent_checkpoint_id"]
+                    else None,
+                    self._load_writes(value["pending_writes"]),
+                )
+
+    def put(
+        self,
+        config: RunnableConfig,
+        checkpoint: Checkpoint,
+        metadata: CheckpointMetadata,
+        new_versions: ChannelVersions,
+    ) -> RunnableConfig:
+        """Save a checkpoint to the database.
+
+        This method saves a checkpoint to the Postgres database. The checkpoint is associated
+        with the provided config and its parent config (if any).
+
+        Args:
+            config (RunnableConfig): The config to associate with the checkpoint.
+            checkpoint (Checkpoint): The checkpoint to save.
+            metadata (CheckpointMetadata): Additional metadata to save with the checkpoint.
+            new_versions (ChannelVersions): New channel versions as of this write.
+
+        Returns:
+            RunnableConfig: Updated configuration after storing the checkpoint.
+
+        Examples:
+
+            >>> from langgraph.checkpoint.postgres import PostgresSaver
+            >>> DB_URI = "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable"
+            >>> with PostgresSaver.from_conn_string(DB_URI) as memory:
+            >>>     config = {"configurable": {"thread_id": "1", "checkpoint_ns": ""}}
+            >>>     checkpoint = {"ts": "2024-05-04T06:32:42.235444+00:00", "id": "1ef4f797-8335-6428-8001-8a1503f9b875", "data": {"key": "value"}}
+            >>>     saved_config = memory.put(config, checkpoint, {"source": "input", "step": 1, "writes": {"key": "value"}}, {})
+            >>> print(saved_config)
+            {'configurable': {'thread_id': '1', 'checkpoint_ns': '', 'checkpoint_id': '1ef4f797-8335-6428-8001-8a1503f9b875'}}
+        """
+        configurable = config["configurable"].copy()
+        thread_id = configurable.pop("thread_id")
+        checkpoint_ns = configurable.pop("checkpoint_ns")
+        checkpoint_id = configurable.pop(
+            "checkpoint_id", configurable.pop("thread_ts", None)
+        )
+
+        copy = checkpoint.copy()
+        next_config = {
+            "configurable": {
+                "thread_id": thread_id,
+                "checkpoint_ns": checkpoint_ns,
+                "checkpoint_id": checkpoint["id"],
+            }
+        }
+
+        with self._cursor(pipeline=True) as cur:
+            cur.executemany(
+                self.UPSERT_CHECKPOINT_BLOBS_SQL,
+                self._dump_blobs(
+                    thread_id,
+                    checkpoint_ns,
+                    copy.pop("channel_values"),
+                    new_versions,
+                ),
+            )
+            cur.execute(
+                self.UPSERT_CHECKPOINTS_SQL,
+                (
+                    thread_id,
+                    checkpoint_ns,
+                    checkpoint["id"],
+                    checkpoint_id,
+                    Jsonb(self._dump_checkpoint(copy)),
+                    self._dump_metadata(metadata),
+                ),
+            )
+        return next_config
+
+    def put_writes(
+        self,
+        config: RunnableConfig,
+        writes: List[tuple[str, Any]],
+        task_id: str,
+    ) -> None:
+        """Store intermediate writes linked to a checkpoint.
+
+        This method saves intermediate writes associated with a checkpoint to the Postgres database.
+
+        Args:
+            config (RunnableConfig): Configuration of the related checkpoint.
+            writes (List[Tuple[str, Any]]): List of writes to store.
+            task_id (str): Identifier for the task creating the writes.
+        """
+        with self._cursor() as cur:
+            cur.executemany(
+                self.UPSERT_CHECKPOINT_WRITES_SQL,
+                self._dump_writes(
+                    config["configurable"]["thread_id"],
+                    config["configurable"]["checkpoint_ns"],
+                    config["configurable"]["checkpoint_id"],
+                    task_id,
+                    writes,
+                ),
+            )
+
+    @contextmanager
+    def _cursor(self, *, pipeline: bool = False) -> Iterator[Cursor]:
+        if self.pipe:
+            # a connection in pipeline mode can be used concurrently
+            # in multiple threads/coroutines, but only one cursor can be
+            # used at a time
+            try:
+                with self.conn.cursor(binary=True) as cur:
+                    yield cur
+            finally:
+                if pipeline:
+                    self.pipe.sync()
+        elif pipeline:
+            # a connection not in pipeline mode can only be used by one
+            # thread/coroutine at a time, so we acquire a lock
+            with self.lock, self.conn.pipeline(), self.conn.cursor(binary=True) as cur:
+                yield cur
+        else:
+            with self.lock, self.conn.cursor(binary=True) as cur:
+                yield cur
@@ -0,0 +1,309 @@
+import asyncio
+from contextlib import asynccontextmanager
+from typing import Any, AsyncIterator, Optional
+
+from langchain_core.runnables import RunnableConfig
+from psycopg import AsyncConnection, AsyncCursor, AsyncPipeline
+from psycopg.errors import UndefinedTable
+from psycopg.rows import dict_row
+from psycopg.types.json import Jsonb
+
+from langgraph.checkpoint.base import (
+    ChannelVersions,
+    Checkpoint,
+    CheckpointMetadata,
+    CheckpointTuple,
+    get_checkpoint_id,
+)
+from langgraph.checkpoint.postgres.base import BasePostgresSaver
+from langgraph.checkpoint.serde.base import SerializerProtocol
+
+
+class AsyncPostgresSaver(BasePostgresSaver):
+    lock: asyncio.Lock
+
+    def __init__(
+        self,
+        conn: AsyncConnection,
+        pipe: Optional[AsyncPipeline] = None,
+        serde: Optional[SerializerProtocol] = None,
+    ) -> None:
+        super().__init__(serde=serde)
+        self.conn = conn
+        self.pipe = pipe
+        self.lock = asyncio.Lock()
+
+    @classmethod
+    @asynccontextmanager
+    async def from_conn_string(
+        cls, conn_string: str, *, pipeline: bool = False
+    ) -> AsyncIterator["AsyncPostgresSaver"]:
+        """Create a new PostgresSaver instance from a connection string.
+
+        Args:
+            conn_string (str): The Postgres connection info string.
+            pipeline (bool): whether to use AsyncPipeline
+
+        Returns:
+            PostgresSaver: A new PostgresSaver instance.
+        """
+        async with await AsyncConnection.connect(
+            conn_string, autocommit=True, prepare_threshold=0, row_factory=dict_row
+        ) as conn:
+            if pipeline:
+                async with conn.pipeline() as pipe:
+                    yield AsyncPostgresSaver(conn, pipe)
+            else:
+                yield AsyncPostgresSaver(conn)
+
+    async def setup(self) -> None:
+        """Set up the checkpoint database asynchronously.
+
+        This method creates the necessary tables in the Postgres database if they don't
+        already exist and runs database migrations. It MUST be called directly by the user
+        the first time checkpointer is used.
+        """
+        async with self.lock:
+            async with self.conn.cursor(binary=True) as cur:
+                try:
+                    results = await cur.execute(
+                        "SELECT v FROM checkpoint_migrations ORDER BY v DESC LIMIT 1"
+                    )
+                    version = (await results.fetchone())["v"]
+                except UndefinedTable:
+                    version = -1
+                for v, migration in zip(
+                    range(version + 1, len(self.MIGRATIONS)),
+                    self.MIGRATIONS[version + 1 :],
+                ):
+                    await cur.execute(migration)
+                    await cur.execute(
+                        f"INSERT INTO checkpoint_migrations (v) VALUES ({v})"
+                    )
+            if self.pipe:
+                await self.pipe.sync()
+
+    async def alist(
+        self,
+        config: Optional[RunnableConfig],
+        *,
+        filter: Optional[dict[str, Any]] = None,
+        before: Optional[RunnableConfig] = None,
+        limit: Optional[int] = None,
+    ) -> AsyncIterator[CheckpointTuple]:
+        """List checkpoints from the database asynchronously.
+
+        This method retrieves a list of checkpoint tuples from the Postgres database based
+        on the provided config. The checkpoints are ordered by checkpoint ID in descending order (newest first).
+
+        Args:
+            config (Optional[RunnableConfig]): Base configuration for filtering checkpoints.
+            filter (Optional[Dict[str, Any]]): Additional filtering criteria for metadata.
+            before (Optional[RunnableConfig]): If provided, only checkpoints before the specified checkpoint ID are returned. Defaults to None.
+            limit (Optional[int]): Maximum number of checkpoints to return.
+
+        Yields:
+            AsyncIterator[CheckpointTuple]: An asynchronous iterator of matching checkpoint tuples.
+        """
+        where, args = self._search_where(config, filter, before)
+        query = self.SELECT_SQL + where + " ORDER BY checkpoint_id DESC"
+        if limit:
+            query += f" LIMIT {limit}"
+        # if we change this to use .stream() we need to make sure to close the cursor
+        async for value in await self.conn.execute(query, args, binary=True):
+            yield CheckpointTuple(
+                {
+                    "configurable": {
+                        "thread_id": value["thread_id"],
+                        "checkpoint_ns": value["checkpoint_ns"],
+                        "checkpoint_id": value["checkpoint_id"],
+                    }
+                },
+                {
+                    **self._load_checkpoint(value["checkpoint"]),
+                    "channel_values": await asyncio.to_thread(
+                        self._load_blobs, value["channel_values"]
+                    ),
+                },
+                self._load_metadata(value["metadata"]),
+                {
+                    "configurable": {
+                        "thread_id": value["thread_id"],
+                        "checkpoint_ns": value["checkpoint_ns"],
+                        "checkpoint_id": value["parent_checkpoint_id"],
+                    }
+                }
+                if value["parent_checkpoint_id"]
+                else None,
+            )
+
+    async def aget_tuple(self, config: RunnableConfig) -> Optional[CheckpointTuple]:
+        """Get a checkpoint tuple from the database asynchronously.
+
+        This method retrieves a checkpoint tuple from the Postgres database based on the
+        provided config. If the config contains a "checkpoint_id" key, the checkpoint with
+        the matching thread ID and "checkpoint_id" is retrieved. Otherwise, the latest checkpoint
+        for the given thread ID is retrieved.
+
+        Args:
+            config (RunnableConfig): The config to use for retrieving the checkpoint.
+
+        Returns:
+            Optional[CheckpointTuple]: The retrieved checkpoint tuple, or None if no matching checkpoint was found.
+        """
+        thread_id = config["configurable"]["thread_id"]
+        checkpoint_id = get_checkpoint_id(config)
+        checkpoint_ns = config["configurable"].get("checkpoint_ns", "")
+        if checkpoint_id:
+            args = (thread_id, checkpoint_ns, checkpoint_id)
+            where = "WHERE thread_id = %s AND checkpoint_ns = %s AND checkpoint_id = %s"
+        else:
+            args = (thread_id, checkpoint_ns)
+            where = "WHERE thread_id = %s AND checkpoint_ns = %s ORDER BY checkpoint_id DESC LIMIT 1"
+
+        async with self._cursor() as cur:
+            cur = await self.conn.execute(
+                self.SELECT_SQL + where,
+                args,
+                binary=True,
+            )
+
+            async for value in cur:
+                return CheckpointTuple(
+                    {
+                        "configurable": {
+                            "thread_id": thread_id,
+                            "checkpoint_ns": checkpoint_ns,
+                            "checkpoint_id": value["checkpoint_id"],
+                        }
+                    },
+                    {
+                        **self._load_checkpoint(value["checkpoint"]),
+                        "channel_values": await asyncio.to_thread(
+                            self._load_blobs, value["channel_values"]
+                        ),
+                    },
+                    self._load_metadata(value["metadata"]),
+                    {
+                        "configurable": {
+                            "thread_id": thread_id,
+                            "checkpoint_ns": checkpoint_ns,
+                            "checkpoint_id": value["parent_checkpoint_id"],
+                        }
+                    }
+                    if value["parent_checkpoint_id"]
+                    else None,
+                    await asyncio.to_thread(self._load_writes, value["pending_writes"]),
+                )
+
+    async def aput(
+        self,
+        config: RunnableConfig,
+        checkpoint: Checkpoint,
+        metadata: CheckpointMetadata,
+        new_versions: ChannelVersions,
+    ) -> RunnableConfig:
+        """Save a checkpoint to the database asynchronously.
+
+        This method saves a checkpoint to the Postgres database. The checkpoint is associated
+        with the provided config and its parent config (if any).
+
+        Args:
+            config (RunnableConfig): The config to associate with the checkpoint.
+            checkpoint (Checkpoint): The checkpoint to save.
+            metadata (CheckpointMetadata): Additional metadata to save with the checkpoint.
+            new_versions (ChannelVersions): New channel versions as of this write.
+
+        Returns:
+            RunnableConfig: Updated configuration after storing the checkpoint.
+        """
+        configurable = config["configurable"].copy()
+        thread_id = configurable.pop("thread_id")
+        checkpoint_ns = configurable.pop("checkpoint_ns")
+        checkpoint_id = configurable.pop(
+            "checkpoint_id", configurable.pop("thread_ts", None)
+        )
+
+        copy = checkpoint.copy()
+        next_config = {
+            "configurable": {
+                "thread_id": thread_id,
+                "checkpoint_ns": checkpoint_ns,
+                "checkpoint_id": checkpoint["id"],
+            }
+        }
+
+        async with self._cursor(pipeline=True) as cur:
+            await cur.executemany(
+                self.UPSERT_CHECKPOINT_BLOBS_SQL,
+                await asyncio.to_thread(
+                    self._dump_blobs,
+                    thread_id,
+                    checkpoint_ns,
+                    copy.pop("channel_values"),
+                    new_versions,
+                ),
+            )
+            await cur.execute(
+                self.UPSERT_CHECKPOINTS_SQL,
+                (
+                    thread_id,
+                    checkpoint_ns,
+                    checkpoint["id"],
+                    checkpoint_id,
+                    Jsonb(self._dump_checkpoint(copy)),
+                    self._dump_metadata(metadata),
+                ),
+            )
+        return next_config
+
+    async def aput_writes(
+        self,
+        config: RunnableConfig,
+        writes: list[tuple[str, Any]],
+        task_id: str,
+    ) -> None:
+        """Store intermediate writes linked to a checkpoint asynchronously.
+
+        This method saves intermediate writes associated with a checkpoint to the database.
+
+        Args:
+            config (RunnableConfig): Configuration of the related checkpoint.
+            writes (Sequence[Tuple[str, Any]]): List of writes to store, each as (channel, value) pair.
+            task_id (str): Identifier for the task creating the writes.
+        """
+        async with self._cursor() as cur:
+            await cur.executemany(
+                self.UPSERT_CHECKPOINT_WRITES_SQL,
+                await asyncio.to_thread(
+                    self._dump_writes,
+                    config["configurable"]["thread_id"],
+                    config["configurable"]["checkpoint_ns"],
+                    config["configurable"]["checkpoint_id"],
+                    task_id,
+                    writes,
+                ),
+            )
+
+    @asynccontextmanager
+    async def _cursor(self, *, pipeline: bool = False) -> AsyncIterator[AsyncCursor]:
+        if self.pipe:
+            # a connection in pipeline mode can be used concurrently
+            # in multiple threads/coroutines, but only one cursor can be
+            # used at a time
+            try:
+                async with self.conn.cursor(binary=True) as cur:
+                    yield cur
+            finally:
+                if pipeline:
+                    await self.pipe.sync()
+        elif pipeline:
+            # a connection not in pipeline mode can only be used by one
+            # thread/coroutine at a time, so we acquire a lock
+            async with self.lock, self.conn.pipeline(), self.conn.cursor(
+                binary=True
+            ) as cur:
+                yield cur
+        else:
+            async with self.lock, self.conn.cursor(binary=True) as cur:
+                yield cur
@@ -0,0 +1,273 @@
+from base64 import b64decode, b64encode
+from hashlib import md5
+from typing import Any, List, Optional, Tuple
+
+from langchain_core.runnables import RunnableConfig
+from psycopg.types.json import Jsonb
+
+from langgraph.checkpoint.base import (
+    BaseCheckpointSaver,
+    Checkpoint,
+    EmptyChannelError,
+    get_checkpoint_id,
+)
+from langgraph.checkpoint.serde.jsonplus import JsonPlusSerializer
+from langgraph.checkpoint.serde.types import ChannelProtocol
+
+MetadataInput = Optional[dict[str, Any]]
+
+"""
+To add a new migration, add a new string to the MIGRATIONS list.
+The position of the migration in the list is the version number.
+"""
+MIGRATIONS = [
+    """CREATE TABLE IF NOT EXISTS checkpoint_migrations (
+    v INTEGER PRIMARY KEY
+);""",
+    """CREATE TABLE IF NOT EXISTS checkpoints (
+    thread_id TEXT NOT NULL,
+    checkpoint_ns TEXT NOT NULL DEFAULT '',
+    checkpoint_id TEXT NOT NULL,
+    parent_checkpoint_id TEXT,
+    type TEXT,
+    checkpoint JSONB NOT NULL,
+    metadata JSONB NOT NULL DEFAULT '{}',
+    PRIMARY KEY (thread_id, checkpoint_ns, checkpoint_id)
+);""",
+    """CREATE TABLE IF NOT EXISTS checkpoint_blobs (
+    thread_id TEXT NOT NULL,
+    checkpoint_ns TEXT NOT NULL DEFAULT '',
+    channel TEXT NOT NULL,
+    version TEXT NOT NULL,
+    type TEXT NOT NULL,
+    blob BYTEA,
+    PRIMARY KEY (thread_id, checkpoint_ns, channel, version)
+);""",
+    """CREATE TABLE IF NOT EXISTS checkpoint_writes (
+    thread_id TEXT NOT NULL,
+    checkpoint_ns TEXT NOT NULL DEFAULT '',
+    checkpoint_id TEXT NOT NULL,
+    task_id TEXT NOT NULL,
+    idx INTEGER NOT NULL,
+    channel TEXT NOT NULL,
+    type TEXT,
+    blob BYTEA NOT NULL,
+    PRIMARY KEY (thread_id, checkpoint_ns, checkpoint_id, task_id, idx)
+);""",
+    "ALTER TABLE checkpoint_blobs ALTER COLUMN blob DROP not null;",
+]
+
+SELECT_SQL = """
+select
+    thread_id,
+    checkpoint,
+    checkpoint_ns,
+    checkpoint_id,
+    parent_checkpoint_id,
+    metadata,
+    (
+        select array_agg(array[bl.channel::bytea, bl.type::bytea, bl.blob])
+        from jsonb_each_text(checkpoint -> 'channel_versions')
+        inner join checkpoint_blobs bl
+            on bl.thread_id = checkpoints.thread_id
+            and bl.checkpoint_ns = checkpoints.checkpoint_ns
+            and bl.channel = jsonb_each_text.key
+            and bl.version = jsonb_each_text.value
+    ) as channel_values,
+    (
+        select
+        array_agg(array[cw.task_id::text::bytea, cw.channel::bytea, cw.type::bytea, cw.blob])
+        from checkpoint_writes cw
+        where cw.thread_id = checkpoints.thread_id
+            and cw.checkpoint_ns = checkpoints.checkpoint_ns
+            and cw.checkpoint_id = checkpoints.checkpoint_id
+    ) as pending_writes
+from checkpoints """
+
+UPSERT_CHECKPOINT_BLOBS_SQL = """
+    INSERT INTO checkpoint_blobs (thread_id, checkpoint_ns, channel, version, type, blob)
+    VALUES (%s, %s, %s, %s, %s, %s)
+    ON CONFLICT (thread_id, checkpoint_ns, channel, version) DO NOTHING
+"""
+
+UPSERT_CHECKPOINTS_SQL = """
+    INSERT INTO checkpoints (thread_id, checkpoint_ns, checkpoint_id, parent_checkpoint_id, checkpoint, metadata)
+    VALUES (%s, %s, %s, %s, %s, %s)
+    ON CONFLICT (thread_id, checkpoint_ns, checkpoint_id)
+    DO UPDATE SET
+        checkpoint = EXCLUDED.checkpoint,
+        metadata = EXCLUDED.metadata;
+"""
+
+UPSERT_CHECKPOINT_WRITES_SQL = """
+    INSERT INTO checkpoint_writes (thread_id, checkpoint_ns, checkpoint_id, task_id, idx, channel, type, blob)
+    VALUES (%s, %s, %s, %s, %s, %s, %s, %s)
+    ON CONFLICT (thread_id, checkpoint_ns, checkpoint_id, task_id, idx) DO NOTHING
+"""
+
+
+class BasePostgresSaver(BaseCheckpointSaver):
+    SELECT_SQL = SELECT_SQL
+    MIGRATIONS = MIGRATIONS
+    UPSERT_CHECKPOINT_BLOBS_SQL = UPSERT_CHECKPOINT_BLOBS_SQL
+    UPSERT_CHECKPOINTS_SQL = UPSERT_CHECKPOINTS_SQL
+    UPSERT_CHECKPOINT_WRITES_SQL = UPSERT_CHECKPOINT_WRITES_SQL
+    jsonplus_serde = JsonPlusSerializer()
+
+    def _load_checkpoint(self, checkpoint: dict[str, Any]) -> Checkpoint:
+        if len(checkpoint["pending_sends"]) == 2 and all(
+            isinstance(a, str) for a in checkpoint["pending_sends"]
+        ):
+            type, bs = checkpoint["pending_sends"]
+            return {
+                **checkpoint,
+                "pending_sends": self.serde.loads_typed((type, b64decode(bs))),
+            }
+
+        return checkpoint
+
+    def _dump_checkpoint(self, checkpoint: Checkpoint) -> dict[str, Any]:
+        type, bs = self.serde.dumps_typed(checkpoint["pending_sends"])
+        return {
+            **checkpoint,
+            "pending_sends": (type, b64encode(bs).decode()),
+        }
+
+    def _load_blobs(
+        self, blob_values: list[tuple[bytes, bytes, bytes]]
+    ) -> dict[str, Any]:
+        if not blob_values:
+            return {}
+        return {
+            k.decode(): self.serde.loads_typed((t.decode(), v))
+            for k, t, v in blob_values
+            if t.decode() != "empty"
+        }
+
+    def _dump_blobs(
+        self,
+        thread_id: str,
+        checkpoint_ns: str,
+        values: dict[str, Any],
+        versions: dict[str, str],
+    ) -> list[tuple[str, str, str, str, str, bytes]]:
+        if not versions:
+            return []
+
+        return [
+            (
+                thread_id,
+                checkpoint_ns,
+                k,
+                ver,
+                *(
+                    self.serde.dumps_typed(values[k])
+                    if k in values
+                    else ("empty", None)
+                ),
+            )
+            for k, ver in versions.items()
+        ]
+
+    def _load_writes(
+        self, writes: list[tuple[bytes, bytes, bytes, bytes]]
+    ) -> list[tuple[str, str, Any]]:
+        return (
+            [
+                (
+                    tid.decode(),
+                    channel.decode(),
+                    self.serde.loads_typed((t.decode(), v)),
+                )
+                for tid, channel, t, v in writes
+            ]
+            if writes
+            else []
+        )
+
+    def _dump_writes(
+        self,
+        thread_id: str,
+        checkpoint_ns: str,
+        checkpoint_id: str,
+        task_id: str,
+        writes: list[tuple[str, Any]],
+    ) -> list[tuple[str, str, str, int, str, str, bytes]]:
+        return [
+            (
+                thread_id,
+                checkpoint_ns,
+                checkpoint_id,
+                task_id,
+                idx,
+                channel,
+                *self.serde.dumps_typed(value),
+            )
+            for idx, (channel, value) in enumerate(writes)
+        ]
+
+    def _load_metadata(self, metadata: dict[str, Any]) -> dict[str, Any]:
+        return self.jsonplus_serde.loads(self.jsonplus_serde.dumps(metadata))
+
+    def _dump_metadata(self, metadata) -> str:
+        serialized_metadata_type, serialized_metadata = self.jsonplus_serde.dumps_typed(
+            metadata
+        )
+        if serialized_metadata_type != "json":
+            raise TypeError(
+                f"Failed to properly serialize metadata -- expected 'json', got '{serialized_metadata_type}'"
+            )
+        return serialized_metadata.decode()
+
+    def get_next_version(self, current: Optional[str], channel: ChannelProtocol) -> str:
+        if current is None:
+            current_v = 0
+        elif isinstance(current, int):
+            current_v = current
+        else:
+            current_v = int(current.split(".")[0])
+        next_v = current_v + 1
+        try:
+            next_h = md5(self.serde.dumps_typed(channel.checkpoint())[1]).hexdigest()
+        except EmptyChannelError:
+            next_h = ""
+        return f"{next_v:032}.{next_h}"
+
+    def _search_where(
+        self,
+        config: Optional[RunnableConfig],
+        filter: MetadataInput,
+        before: Optional[RunnableConfig] = None,
+    ) -> Tuple[str, List[Any]]:
+        """Return WHERE clause predicates for alist() given config, filter, cursor.
+
+        This method returns a tuple of a string and a tuple of values. The string
+        is the parametered WHERE clause predicate (including the WHERE keyword):
+        "WHERE column1 = $1 AND column2 IS $2". The list of values contains the
+        values for each of the corresponding parameters.
+        """
+        wheres = []
+        param_values = []
+
+        # construct predicate for config filter
+        if config:
+            wheres.append("thread_id = %s ")
+            param_values.append(config["configurable"]["thread_id"])
+            checkpoint_ns = config["configurable"].get("checkpoint_ns", "")
+            wheres.append("checkpoint_ns = %s")
+            param_values.append(checkpoint_ns)
+
+        # construct predicate for metadata filter
+        if filter:
+            wheres.append("metadata @> %s ")
+            param_values.append(Jsonb(filter))
+
+        # construct predicate for `before`
+        if before is not None:
+            wheres.append("checkpoint_id < %s ")
+            param_values.append(get_checkpoint_id(before))
+
+        return (
+            "WHERE " + " AND ".join(wheres) if wheres else "",
+            param_values,
+        )
--- a/Show More
+++ b/Show More