fix(prebuilt): default ToolRuntime tools to empty list (#7651)

Backports the ToolRuntime fix onto the release branch and bumps to .
This makes default to an empty list when not provided and includes a
focused regression test, with the prebuilt lockfile updated to match the
version bump.

Created with [Deep Agents
CLI](https://docs.langchain.com/oss/python/deepagents/cli/overview)
using gpt-5.4 (provider: openai).

libs/langgraph/uv.lock

@@ -1742,7 +1742,7 @@ test = [
 
 [[package]]
 name = "langgraph-prebuilt"
-version = "1.0.12"
+version = "1.0.13"
 source = { editable = "../prebuilt" }
 dependencies = [
     { name = "langchain-core" },

libs/prebuilt/langgraph/prebuilt/tool_node.py

@@ -44,7 +44,7 @@ import inspect
 import json
 from collections.abc import Awaitable, Callable
 from copy import copy, deepcopy
-from dataclasses import dataclass, replace
+from dataclasses import dataclass, field, replace
 from types import UnionType
 from typing import (
     TYPE_CHECKING,
@@ -1722,9 +1722,9 @@ class ToolRuntime(_DirectlyInjectedToolArg, Generic[ContextT, StateT]):
     context: ContextT
     config: RunnableConfig
     stream_writer: StreamWriter
-    tools: list[BaseTool]
     tool_call_id: str | None
     store: BaseStore | None
+    tools: list[BaseTool] = field(default_factory=list)
     execution_info: ExecutionInfo | None = None
     server_info: ServerInfo | None = None
 

libs/prebuilt/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "langgraph-prebuilt"
-version = "1.0.12"
+version = "1.0.13"
 description = "Library with high-level APIs for creating and executing LangGraph agents and tools."
 authors = []
 requires-python = ">=3.10"

libs/prebuilt/tests/test_tool_node.py

@@ -2016,6 +2016,19 @@ async def test_tool_node_inject_runtime_dynamic_tool_via_wrap_tool_call_async()
     assert tool_message.tool_call_id == "call_dynamic_2"
 
 
+def test_tool_runtime_defaults_tools_to_empty_list() -> None:
+    runtime = ToolRuntime(
+        state={},
+        context=None,
+        config={},
+        stream_writer=lambda *args, **kwargs: None,
+        tool_call_id=None,
+        store=None,
+    )
+
+    assert runtime.tools == []
+
+
 def test_tool_runtime_forwards_execution_info_server_info_and_tools() -> None:
     """Test that execution_info, server_info, and tools are forwarded from Runtime to ToolRuntime."""
     from langgraph.runtime import ExecutionInfo, ServerInfo

libs/prebuilt/uv.lock

@@ -490,7 +490,7 @@ test = [
 
 [[package]]
 name = "langgraph-prebuilt"
-version = "1.0.12"
+version = "1.0.13"
 source = { editable = "." }
 dependencies = [
     { name = "langchain-core" },

libs/sdk-py/uv.lock

@@ -413,7 +413,7 @@ test = [
 
 [[package]]
 name = "langgraph-prebuilt"
-version = "1.0.12"
+version = "1.0.13"
 source = { editable = "../prebuilt" }
 dependencies = [
     { name = "langchain-core" },