product · inferred from evidence
ToolNode
A component provided by LangGraph that enforces correct pairing of tool calls and ToolMessages.
- "fake_search is not a valid tool, try one of [tool]" in LangGraph
Fixes "[name] is not a valid tool, try one of [tool]" when a custom LangGraph tool is rejected at runtime. Use when built-in tools work but your custom function gets this error. Cause: tools registered in only one of the two places. Fix: pa