Error troubleshooting

This page contains guides around resolving common errors you may find while building with LangChain and LangGraph.

Errors referenced below will have an lc_error_code property corresponding to one of the below codes when they are thrown in code.

• GRAPH_RECURSION_LIMIT
• INVALID_CHAT_HISTORY
• INVALID_CONCURRENT_GRAPH_UPDATE
• INVALID_GRAPH_NODE_RETURN_VALUE
• INVALID_PROMPT_INPUT
• INVALID_TOOL_RESULTS
• MESSAGE_COERCION_FAILURE
• MISSING_CHECKPOINTER
• MODEL_AUTHENTICATION
• MODEL_NOT_FOUND
• MODEL_RATE_LIMIT
• MULTIPLE_SUBGRAPHS
• OUTPUT_PARSING_FAILURE

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