Errors

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.

Error 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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