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    PythonlanggraphErrors

    Errors

    Classes

    Class

    ErrorCode

    Class

    GraphBubbleUp

    Class

    GraphDrained

    Raised when a graph run exits early due to a drain request.

    This indicates the graph stopped cooperatively at a superstep boundary because RunControl.request_drain() was called (e.g., in response t

    Class

    GraphRecursionError

    Raised when the graph has exhausted the maximum number of steps.

    This prevents infinite loops. To increase the maximum number of steps, run your graph with a config specifying a higher `recursion_lim

    Class

    InvalidUpdateError

    Raised when attempting to update a channel with an invalid set of updates.

    Troubleshooting guides:

    • [INVALID_CONCURRENT_GRAPH_UPDATE](https://docs.langchain.com/oss/python/langgraph/INVALID_CONCU
    Class

    GraphInterrupt

    Raised when a subgraph is interrupted, suppressed by the root graph. Never raised directly, or surfaced to the user.

    Class

    ParentCommand

    Class

    EmptyInputError

    Raised when graph receives an empty input.

    Class

    TaskNotFound

    Raised when the executor is unable to find a task (for distributed mode).

    Class

    NodeError

    Failure context passed to a node-level error handler.

    Inject by adding a parameter typed NodeError to a handler registered via StateGraph.add_node(..., error_handler=...):

    def handler(
    
    Class

    NodeCancelledError

    Raised when a node body raises asyncio.CancelledError itself.

    asyncio.CancelledError is a BaseException and the pregel runner treats cancelled task futures as silent tear-down (e.g. when

    Class

    NodeTimeoutError

    Raised when a node invocation exceeds one of its configured timeouts.

    Does not inherit from the built-in TimeoutError (a subclass of OSError) so that the default RetryPolicy treats it as re

    Class

    NodeInterrupt

    deprecated

    Raised by a node to interrupt execution.

    Functions

    Function

    create_error_message