langchain-middleware

You can add human-in-the-loop approval by configuring a middleware that pauses LangChain agent execution before dangerous tool calls to require explicit human authorization, editing, or rejection.

Intercepting LangGraph tool calls is best handled by custom middleware hooks that capture tool invocations mid-execution to apply custom logging, error handling, or retry logic.

Yes, you can resume agent execution using command resume patterns that leverage thread-safe state management to seamlessly continue processing after a human intervention.

Yes, LangGraph is required as a dependency alongside LangChain and Zod to facilitate the thread-safe state persistence needed for command resume patterns.

Autonomous agents execute sensitive calls directly when no human-in-the-loop middleware is present, making structured middleware patterns necessary to require explicit approval for dangerous tool calls.

Middleware for agent safety requires structured command-based execution and state persistence to maintain production-grade reliability, meaning poorly managed thread-safe states can disrupt the command resume workflow.