From f26ca077167cac49358dc8df7a13388c7d838450 Mon Sep 17 00:00:00 2001
From: Sydney Runkle <sydneymarierunkle@gmail.com>
Date: Thu, 4 Sep 2025 16:05:08 -0400
Subject: [PATCH] minimalistic tool registration

---
 libs/langgraph/langgraph/agent/__init__.py        | 15 +++++++++++----
 .../langgraph/langgraph/agent/middleware/swarm.py |  5 +++--
 .../langgraph/agent/middleware/tool_calls.py      | 11 ++++++++++-
 libs/langgraph/langgraph/agent/types.py           |  3 +++
 4 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/libs/langgraph/langgraph/agent/__init__.py b/libs/langgraph/langgraph/agent/__init__.py
index 3b428d759..9afec3a6b 100644
--- a/libs/langgraph/langgraph/agent/__init__.py
+++ b/libs/langgraph/langgraph/agent/__init__.py
@@ -43,8 +43,14 @@ def create_agent(
 
         model = cast(BaseChatModel, init_chat_model(model))
 
-    # init tool node
-    tool_node = tools if isinstance(tools, ToolNode) else ToolNode(tools=tools)
+    if isinstance(tools, list):
+        all_tools = [t for m in middleware for t in m.tools] + list(tools)
+        tool_node = ToolNode(tools=all_tools)
+        default_tools = tools
+    else:
+        # TODO: what do we do when middleware tools are specified, plus a ToolNode is used?
+        tool_node = tools
+        default_tools = list(tool_node.tools_by_name.values())
 
     # validate middleware
     assert len({m.__class__.__name__ for m in middleware}) == len(middleware), (
@@ -77,7 +83,7 @@ def create_agent(
     def model_request(state: AgentState) -> AgentState:
         request = state.model_request or ModelRequest(
             model=model,
-            tools=list(tool_node.tools_by_name.values()),
+            tools=default_tools,
             system_prompt=system_prompt,
             response_format=response_format,
             messages=state.messages,
@@ -85,6 +91,7 @@ def create_agent(
         )
 
         # prepare messages
+        print(request.system_prompt)
         if request.system_prompt:
             messages = [SystemMessage(request.system_prompt)] + request.messages
         else:
@@ -127,7 +134,7 @@ def create_agent(
 
                 default_model_request = ModelRequest(
                     model=model,
-                    tools=list(tool_node.tools_by_name.values()),
+                    tools=default_tools,
                     system_prompt=system_prompt,
                     response_format=response_format,
                     messages=state.messages,
diff --git a/libs/langgraph/langgraph/agent/middleware/swarm.py b/libs/langgraph/langgraph/agent/middleware/swarm.py
index ad55280b6..364bf8e8f 100644
--- a/libs/langgraph/langgraph/agent/middleware/swarm.py
+++ b/libs/langgraph/langgraph/agent/middleware/swarm.py
@@ -15,8 +15,8 @@ class SwarmAgent:
     tools: list[BaseTool]
 
 
-class SwarmMiddleware(AgentMiddleware):
-    """Swarm middleware.
+class MultiAgentMiddleware(AgentMiddleware):
+    """Multi agent middleware (enabling swarm like behavior).
 
     TODOs:
     * Support create_agent for handoffs
@@ -59,6 +59,7 @@ class SwarmMiddleware(AgentMiddleware):
             request.tools = agent.tools
 
         request.tools.extend(self.handoff_tools)
+
         return request
 
     def after_model(self, state) -> State | None:
diff --git a/libs/langgraph/langgraph/agent/middleware/tool_calls.py b/libs/langgraph/langgraph/agent/middleware/tool_calls.py
index e55d4b9ee..7e4cee6ad 100644
--- a/libs/langgraph/langgraph/agent/middleware/tool_calls.py
+++ b/libs/langgraph/langgraph/agent/middleware/tool_calls.py
@@ -2,6 +2,7 @@ from dataclasses import dataclass, field
 from typing import Annotated, Any, Dict, List, cast
 
 from langchain_core.messages import AIMessage
+from typing_extensions import Annotated
 
 from langgraph.agent.types import AgentJump, AgentMiddleware, AgentState, AgentUpdate
 
@@ -11,7 +12,15 @@ class ToolCallLimitMiddleware(AgentMiddleware):
 
     @dataclass
     class State(AgentMiddleware.State):
-        tool_call_count: dict[str, int] = field(default_factory=dict)
+        important: Annotated[dict[str, int], Input, Output] = field(default_factory=dict)
+
+    @dataclass
+    class InputState(AgentMiddleware.State):
+        important: dict[str, int]
+
+    @dataclass
+    class OutputState(AgentMiddleware.State):
+        important: dict[str, int]
 
     def __init__(self, tool_limits: dict[str, int]):
         self.tool_limits = tool_limits
diff --git a/libs/langgraph/langgraph/agent/types.py b/libs/langgraph/langgraph/agent/types.py
index 2dc139692..32c457e39 100644
--- a/libs/langgraph/langgraph/agent/types.py
+++ b/libs/langgraph/langgraph/agent/types.py
@@ -12,6 +12,7 @@ from typing_extensions import TypedDict
 
 from langgraph.channels.ephemeral_value import EphemeralValue
 from langgraph.graph.message import Messages, add_messages
+from langgraph.runtime import Runtime
 
 ResponseFormat = dict | type[BaseModel]
 JumpTo = Literal["tools", "model", "__end__"]
@@ -39,6 +40,8 @@ class AgentMiddleware:
     class State(AgentState):
         pass
 
+    tools: list[BaseTool]
+
     def before_model(self, state: State) -> AgentUpdate | AgentJump | None:
         pass