LangChain Tool Wrapper Adds Human Approval via Slack Before Agent Actions Run

A new open-source integration called AgentGate lets developers add human-in-the-loop approval to LangChain agents in minutes, without rewriting existing tool logic. When an agent attempts a high-stakes action — such as sending an email, deploying code, or moving money — the tool pauses execution and posts an approval request to Slack or Microsoft Teams. A human reviewer can then approve or reject the action, with rejections requiring a stated reason that is returned to the agent as context. If no response is received within a configurable timeout, the action defaults to rejected rather than proceeding. The wrapper is designed as a drop-in replacement for existing BaseTool implementations, requiring only a few lines of additional code.