How to Fix LangChain AgentExecutor Not Calling Tools AgentExecutor's verbose trace shows it choosing a tool, then the chain just finishes - no error, no tool result. Here's why, and the five-check fix.
Fix LangChain create_react_agent 'unexpected keyword argument prompt' The TypeError comes from a kwarg rename between langgraph versions - or the wrong create_react_agent import entirely. Here's how to tell which and fix it.
Fix LangChain Output Parsing Errors (handle_parsing_errors=True) handle_parsing_errors=True only retries LangChain's free-text ReAct loop -- it can't fix a model that won't format output reliably. Here's what actually works.
Best AI Agent Framework for Node.js Developers in 2026 Mastra, Vercel AI SDK, LangChain.js, or the OpenAI Agents JS SDK? Here's the Node-specific ranking most 2026 roundups skip.
Best AI Agent Framework for Python Developers in 2026 LangGraph, Pydantic AI, CrewAI, and the OpenAI Agents SDK ranked for Python teams in 2026 - plus why AutoGen is no longer the safe default.
LangChain vs LangGraph: when to use each for AI agents LangChain is for linear pipelines. LangGraph is for agents that loop, checkpoint state, and wait for human approval. Here is the exact decision criteria.
How to fix LangChain MultiServerMCPClient NotImplementedError on Windows MultiServerMCPClient raises NotImplementedError on Windows because asyncio does not support Unix sockets. Fix: pass transport="streamable_http" or run inside WSL2. Full workaround inside.
LangChain "Agent stopped due to iteration limit" error: how to fix Why the "Agent stopped due to iteration limit or time limit" error fires - and the five-step fix that beats just raising max_iterations.