service · inferred from evidence
DuckDuckGo
A service mentioned as part of the user's experimentation with simple examples.
- "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