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    Pythonlanggraphpregeltypes
    Moduleā—Since v0.1

    types

    Re-export types moved to langgraph.types

    Attributes

    Functions

    Classes

    View source on GitHub
    attribute
    All: Literal['*']
    attribute
    StreamMode: Literal['values', 'updates', 'checkpoints', 'tasks', 'debug', 'messages', 'custom']
    attribute
    StreamWriter: Callable[[Any], None]
    function
    default_retry_on
    class
    CachePolicy
    class
    PregelExecutableTask
    class
    PregelTask
    class
    RetryPolicy
    class
    StateSnapshot
    class
    StateUpdate
    class
    LangGraphDeprecatedSinceV10

    Special value to indicate that graph should interrupt on all nodes.

    How the stream method should emit outputs.

    • "values": Emit all values in the state after each step, including interrupts. When used with functional API, values are emitted once at the end of the workflow.
    • "updates": Emit only the node or task names and updates returned by the nodes or tasks after each step. If multiple updates are made in the same step (e.g. multiple nodes are run) then those updates are emitted separately.
    • "custom": Emit custom data using from inside nodes or tasks using StreamWriter.
    • "messages": Emit LLM messages token-by-token together with metadata for any LLM invocations inside nodes or tasks.
    • "checkpoints": Emit an event when a checkpoint is created, in the same format as returned by get_state().
    • "tasks": Emit events when tasks start and finish, including their results and errors.
    • "debug": Emit "checkpoints" and "tasks" events for debugging purposes.

    Callable that accepts a single argument and writes it to the output stream. Always injected into nodes if requested as a keyword argument, but it's a no-op when not using stream_mode="custom".

    Configuration for caching nodes.

    A Pregel task.

    Configuration for retrying nodes.

    Snapshot of the state of the graph at the beginning of a step.

    A specific LangGraphDeprecationWarning subclass defining functionality deprecated since LangGraph v1.0.0