# langgraph > Python package 📖 [View in docs](https://reference.langchain.com/python/langgraph) ## Classes - [`ToolOutputMixin`](https://reference.langchain.com/python/langgraph/types/ToolOutputMixin) - [`TaskPayload`](https://reference.langchain.com/python/langgraph/types/TaskPayload) - [`TaskResultPayload`](https://reference.langchain.com/python/langgraph/types/TaskResultPayload) - [`CheckpointTask`](https://reference.langchain.com/python/langgraph/types/CheckpointTask) - [`CheckpointPayload`](https://reference.langchain.com/python/langgraph/types/CheckpointPayload) - [`ValuesStreamPart`](https://reference.langchain.com/python/langgraph/types/ValuesStreamPart) - [`UpdatesStreamPart`](https://reference.langchain.com/python/langgraph/types/UpdatesStreamPart) - [`MessagesStreamPart`](https://reference.langchain.com/python/langgraph/types/MessagesStreamPart) - [`CustomStreamPart`](https://reference.langchain.com/python/langgraph/types/CustomStreamPart) - [`CheckpointStreamPart`](https://reference.langchain.com/python/langgraph/types/CheckpointStreamPart) - [`TasksStreamPart`](https://reference.langchain.com/python/langgraph/types/TasksStreamPart) - [`DebugStreamPart`](https://reference.langchain.com/python/langgraph/types/DebugStreamPart) - [`GraphOutput`](https://reference.langchain.com/python/langgraph/types/GraphOutput) - [`RetryPolicy`](https://reference.langchain.com/python/langgraph/types/RetryPolicy) - [`CachePolicy`](https://reference.langchain.com/python/langgraph/types/CachePolicy) - [`Interrupt`](https://reference.langchain.com/python/langgraph/types/Interrupt) - [`StateUpdate`](https://reference.langchain.com/python/langgraph/types/StateUpdate) - [`PregelTask`](https://reference.langchain.com/python/langgraph/types/PregelTask) - [`CacheKey`](https://reference.langchain.com/python/langgraph/types/CacheKey) - [`PregelExecutableTask`](https://reference.langchain.com/python/langgraph/types/PregelExecutableTask) - [`StateSnapshot`](https://reference.langchain.com/python/langgraph/types/StateSnapshot) - [`Send`](https://reference.langchain.com/python/langgraph/types/Send) - [`Command`](https://reference.langchain.com/python/langgraph/types/Command) - [`Overwrite`](https://reference.langchain.com/python/langgraph/types/Overwrite) - [`ExecutionInfo`](https://reference.langchain.com/python/langgraph/runtime/ExecutionInfo) - [`ServerInfo`](https://reference.langchain.com/python/langgraph/runtime/ServerInfo) - [`Runtime`](https://reference.langchain.com/python/langgraph/runtime/Runtime) - [`ErrorCode`](https://reference.langchain.com/python/langgraph/errors/ErrorCode) - [`GraphRecursionError`](https://reference.langchain.com/python/langgraph/errors/GraphRecursionError) - [`InvalidUpdateError`](https://reference.langchain.com/python/langgraph/errors/InvalidUpdateError) - [`GraphBubbleUp`](https://reference.langchain.com/python/langgraph/errors/GraphBubbleUp) - [`GraphInterrupt`](https://reference.langchain.com/python/langgraph/errors/GraphInterrupt) - [`NodeInterrupt`](https://reference.langchain.com/python/langgraph/errors/NodeInterrupt) - [`ParentCommand`](https://reference.langchain.com/python/langgraph/errors/ParentCommand) - [`EmptyInputError`](https://reference.langchain.com/python/langgraph/errors/EmptyInputError) - [`TaskNotFound`](https://reference.langchain.com/python/langgraph/errors/TaskNotFound) - [`GraphInterruptEvent`](https://reference.langchain.com/python/langgraph/callbacks/GraphInterruptEvent) - [`GraphResumeEvent`](https://reference.langchain.com/python/langgraph/callbacks/GraphResumeEvent) - [`GraphCallbackHandler`](https://reference.langchain.com/python/langgraph/callbacks/GraphCallbackHandler) - [`LangGraphDeprecationWarning`](https://reference.langchain.com/python/langgraph/warnings/LangGraphDeprecationWarning) - [`LangGraphDeprecatedSinceV05`](https://reference.langchain.com/python/langgraph/warnings/LangGraphDeprecatedSinceV05) - [`LangGraphDeprecatedSinceV10`](https://reference.langchain.com/python/langgraph/warnings/LangGraphDeprecatedSinceV10) - [`LangGraphDeprecatedSinceV11`](https://reference.langchain.com/python/langgraph/warnings/LangGraphDeprecatedSinceV11) - [`IsLastStepManager`](https://reference.langchain.com/python/langgraph/managed/is_last_step/IsLastStepManager) - [`RemainingStepsManager`](https://reference.langchain.com/python/langgraph/managed/is_last_step/RemainingStepsManager) - [`ManagedValue`](https://reference.langchain.com/python/langgraph/managed/base/ManagedValue) - [`AnyValue`](https://reference.langchain.com/python/langgraph/channels/any_value/AnyValue) - [`LastValue`](https://reference.langchain.com/python/langgraph/channels/last_value/LastValue) - [`LastValueAfterFinish`](https://reference.langchain.com/python/langgraph/channels/last_value/LastValueAfterFinish) - [`UntrackedValue`](https://reference.langchain.com/python/langgraph/channels/untracked_value/UntrackedValue) - [`BaseChannel`](https://reference.langchain.com/python/langgraph/channels/base/BaseChannel) - [`BinaryOperatorAggregate`](https://reference.langchain.com/python/langgraph/channels/binop/BinaryOperatorAggregate) - [`NamedBarrierValue`](https://reference.langchain.com/python/langgraph/channels/named_barrier_value/NamedBarrierValue) - [`NamedBarrierValueAfterFinish`](https://reference.langchain.com/python/langgraph/channels/named_barrier_value/NamedBarrierValueAfterFinish) - [`EphemeralValue`](https://reference.langchain.com/python/langgraph/channels/ephemeral_value/EphemeralValue) - [`Topic`](https://reference.langchain.com/python/langgraph/channels/topic/Topic) - [`MessageGraph`](https://reference.langchain.com/python/langgraph/graph/message/MessageGraph) - [`MessagesState`](https://reference.langchain.com/python/langgraph/graph/message/MessagesState) - [`UIMessage`](https://reference.langchain.com/python/langgraph/graph/ui/UIMessage) - [`RemoveUIMessage`](https://reference.langchain.com/python/langgraph/graph/ui/RemoveUIMessage) - [`BranchSpec`](https://reference.langchain.com/python/langgraph/graph/_branch/BranchSpec) - [`StateGraph`](https://reference.langchain.com/python/langgraph/graph/state/StateGraph) - [`CompiledStateGraph`](https://reference.langchain.com/python/langgraph/graph/state/CompiledStateGraph) - [`StateNodeSpec`](https://reference.langchain.com/python/langgraph/graph/_node/StateNodeSpec) - [`ReplayState`](https://reference.langchain.com/python/langgraph/_internal/_replay/ReplayState) - [`AsyncQueue`](https://reference.langchain.com/python/langgraph/_internal/_queue/AsyncQueue) - [`Semaphore`](https://reference.langchain.com/python/langgraph/_internal/_queue/Semaphore) - [`SyncQueue`](https://reference.langchain.com/python/langgraph/_internal/_queue/SyncQueue) - [`StrEnum`](https://reference.langchain.com/python/langgraph/_internal/_runnable/StrEnum) - [`RunnableCallable`](https://reference.langchain.com/python/langgraph/_internal/_runnable/RunnableCallable) - [`RunnableSeq`](https://reference.langchain.com/python/langgraph/_internal/_runnable/RunnableSeq) - [`PregelScratchpad`](https://reference.langchain.com/python/langgraph/_internal/_scratchpad/PregelScratchpad) - [`TypedDictLikeV1`](https://reference.langchain.com/python/langgraph/_internal/_typing/TypedDictLikeV1) - [`TypedDictLikeV2`](https://reference.langchain.com/python/langgraph/_internal/_typing/TypedDictLikeV2) - [`DataclassLike`](https://reference.langchain.com/python/langgraph/_internal/_typing/DataclassLike) - [`DeprecatedKwargs`](https://reference.langchain.com/python/langgraph/_internal/_typing/DeprecatedKwargs) - [`entrypoint`](https://reference.langchain.com/python/langgraph/func/entrypoint) - [`final`](https://reference.langchain.com/python/langgraph/func/entrypoint/final) - [`NodeBuilder`](https://reference.langchain.com/python/langgraph/pregel/main/NodeBuilder) - [`Pregel`](https://reference.langchain.com/python/langgraph/pregel/main/Pregel) - [`StreamMessagesHandler`](https://reference.langchain.com/python/langgraph/pregel/_messages/StreamMessagesHandler) - [`WritesProtocol`](https://reference.langchain.com/python/langgraph/pregel/_algo/WritesProtocol) - [`PregelTaskWrites`](https://reference.langchain.com/python/langgraph/pregel/_algo/PregelTaskWrites) - [`Call`](https://reference.langchain.com/python/langgraph/pregel/_algo/Call) - [`LazyAtomicCounter`](https://reference.langchain.com/python/langgraph/pregel/_algo/LazyAtomicCounter) - [`SyncAsyncFuture`](https://reference.langchain.com/python/langgraph/pregel/_call/SyncAsyncFuture) - [`ChannelRead`](https://reference.langchain.com/python/langgraph/pregel/_read/ChannelRead) - [`PregelNode`](https://reference.langchain.com/python/langgraph/pregel/_read/PregelNode) - [`PregelProtocol`](https://reference.langchain.com/python/langgraph/pregel/protocol/PregelProtocol) - [`StreamProtocol`](https://reference.langchain.com/python/langgraph/pregel/protocol/StreamProtocol) - [`RemoteException`](https://reference.langchain.com/python/langgraph/pregel/remote/RemoteException) - [`RemoteGraph`](https://reference.langchain.com/python/langgraph/pregel/remote/RemoteGraph) - [`ChannelWriteEntry`](https://reference.langchain.com/python/langgraph/pregel/_write/ChannelWriteEntry) - [`ChannelWriteTupleEntry`](https://reference.langchain.com/python/langgraph/pregel/_write/ChannelWriteTupleEntry) - [`ChannelWrite`](https://reference.langchain.com/python/langgraph/pregel/_write/ChannelWrite) - [`FunctionNonLocals`](https://reference.langchain.com/python/langgraph/pregel/_utils/FunctionNonLocals) - [`NonLocals`](https://reference.langchain.com/python/langgraph/pregel/_utils/NonLocals) - [`Edge`](https://reference.langchain.com/python/langgraph/pregel/_draw/Edge) - [`TriggerEdge`](https://reference.langchain.com/python/langgraph/pregel/_draw/TriggerEdge) - [`PregelLoop`](https://reference.langchain.com/python/langgraph/pregel/_loop/PregelLoop) - [`SyncPregelLoop`](https://reference.langchain.com/python/langgraph/pregel/_loop/SyncPregelLoop) - [`AsyncPregelLoop`](https://reference.langchain.com/python/langgraph/pregel/_loop/AsyncPregelLoop) - [`Submit`](https://reference.langchain.com/python/langgraph/pregel/_executor/Submit) - [`BackgroundExecutor`](https://reference.langchain.com/python/langgraph/pregel/_executor/BackgroundExecutor) - [`AsyncBackgroundExecutor`](https://reference.langchain.com/python/langgraph/pregel/_executor/AsyncBackgroundExecutor) - [`FuturesDict`](https://reference.langchain.com/python/langgraph/pregel/_runner/FuturesDict) - [`PregelRunner`](https://reference.langchain.com/python/langgraph/pregel/_runner/PregelRunner) ## Functions - [`get_config()`](https://reference.langchain.com/python/langgraph/config/get_config) - [`get_store()`](https://reference.langchain.com/python/langgraph/config/get_store) - [`get_stream_writer()`](https://reference.langchain.com/python/langgraph/config/get_stream_writer) - [`ensure_valid_checkpointer()`](https://reference.langchain.com/python/langgraph/types/ensure_valid_checkpointer) - [`interrupt()`](https://reference.langchain.com/python/langgraph/types/interrupt) - [`get_runtime()`](https://reference.langchain.com/python/langgraph/runtime/get_runtime) - [`create_error_message()`](https://reference.langchain.com/python/langgraph/errors/create_error_message) - [`get_sync_graph_callback_manager_for_config()`](https://reference.langchain.com/python/langgraph/callbacks/get_sync_graph_callback_manager_for_config) - [`get_async_graph_callback_manager_for_config()`](https://reference.langchain.com/python/langgraph/callbacks/get_async_graph_callback_manager_for_config) - [`is_managed_value()`](https://reference.langchain.com/python/langgraph/managed/base/is_managed_value) - [`add_messages()`](https://reference.langchain.com/python/langgraph/graph/message/add_messages) - [`push_message()`](https://reference.langchain.com/python/langgraph/graph/message/push_message) - [`push_ui_message()`](https://reference.langchain.com/python/langgraph/graph/ui/push_ui_message) - [`delete_ui_message()`](https://reference.langchain.com/python/langgraph/graph/ui/delete_ui_message) - [`ui_message_reducer()`](https://reference.langchain.com/python/langgraph/graph/ui/ui_message_reducer) - [`recast_checkpoint_ns()`](https://reference.langchain.com/python/langgraph/_internal/_config/recast_checkpoint_ns) - [`patch_configurable()`](https://reference.langchain.com/python/langgraph/_internal/_config/patch_configurable) - [`patch_checkpoint_map()`](https://reference.langchain.com/python/langgraph/_internal/_config/patch_checkpoint_map) - [`merge_configs()`](https://reference.langchain.com/python/langgraph/_internal/_config/merge_configs) - [`patch_config()`](https://reference.langchain.com/python/langgraph/_internal/_config/patch_config) - [`get_callback_manager_for_config()`](https://reference.langchain.com/python/langgraph/_internal/_config/get_callback_manager_for_config) - [`get_async_callback_manager_for_config()`](https://reference.langchain.com/python/langgraph/_internal/_config/get_async_callback_manager_for_config) - [`ensure_config()`](https://reference.langchain.com/python/langgraph/_internal/_config/ensure_config) - [`chain_future()`](https://reference.langchain.com/python/langgraph/_internal/_future/chain_future) - [`run_coroutine_threadsafe()`](https://reference.langchain.com/python/langgraph/_internal/_future/run_coroutine_threadsafe) - [`get_field_default()`](https://reference.langchain.com/python/langgraph/_internal/_fields/get_field_default) - [`get_enhanced_type_hints()`](https://reference.langchain.com/python/langgraph/_internal/_fields/get_enhanced_type_hints) - [`get_update_as_tuples()`](https://reference.langchain.com/python/langgraph/_internal/_fields/get_update_as_tuples) - [`get_cached_annotated_keys()`](https://reference.langchain.com/python/langgraph/_internal/_fields/get_cached_annotated_keys) - [`get_fields()`](https://reference.langchain.com/python/langgraph/_internal/_pydantic/get_fields) - [`create_model()`](https://reference.langchain.com/python/langgraph/_internal/_pydantic/create_model) - [`is_supported_by_pydantic()`](https://reference.langchain.com/python/langgraph/_internal/_pydantic/is_supported_by_pydantic) - [`default_cache_key()`](https://reference.langchain.com/python/langgraph/_internal/_cache/default_cache_key) - [`set_config_context()`](https://reference.langchain.com/python/langgraph/_internal/_runnable/set_config_context) - [`is_async_callable()`](https://reference.langchain.com/python/langgraph/_internal/_runnable/is_async_callable) - [`is_async_generator()`](https://reference.langchain.com/python/langgraph/_internal/_runnable/is_async_generator) - [`coerce_to_runnable()`](https://reference.langchain.com/python/langgraph/_internal/_runnable/coerce_to_runnable) - [`default_retry_on()`](https://reference.langchain.com/python/langgraph/_internal/_retry/default_retry_on) - [`apply_checkpointer_allowlist()`](https://reference.langchain.com/python/langgraph/_internal/_serde/apply_checkpointer_allowlist) - [`curated_core_allowlist()`](https://reference.langchain.com/python/langgraph/_internal/_serde/curated_core_allowlist) - [`build_serde_allowlist()`](https://reference.langchain.com/python/langgraph/_internal/_serde/build_serde_allowlist) - [`collect_allowlist_from_schemas()`](https://reference.langchain.com/python/langgraph/_internal/_serde/collect_allowlist_from_schemas) - [`task()`](https://reference.langchain.com/python/langgraph/func/task) - [`should_interrupt()`](https://reference.langchain.com/python/langgraph/pregel/_algo/should_interrupt) - [`local_read()`](https://reference.langchain.com/python/langgraph/pregel/_algo/local_read) - [`increment()`](https://reference.langchain.com/python/langgraph/pregel/_algo/increment) - [`apply_writes()`](https://reference.langchain.com/python/langgraph/pregel/_algo/apply_writes) - [`prepare_next_tasks()`](https://reference.langchain.com/python/langgraph/pregel/_algo/prepare_next_tasks) - [`prepare_single_task()`](https://reference.langchain.com/python/langgraph/pregel/_algo/prepare_single_task) - [`prepare_push_task_functional()`](https://reference.langchain.com/python/langgraph/pregel/_algo/prepare_push_task_functional) - [`prepare_push_task_send()`](https://reference.langchain.com/python/langgraph/pregel/_algo/prepare_push_task_send) - [`checkpoint_null_version()`](https://reference.langchain.com/python/langgraph/pregel/_algo/checkpoint_null_version) - [`task_path_str()`](https://reference.langchain.com/python/langgraph/pregel/_algo/task_path_str) - [`sanitize_untracked_values_in_send()`](https://reference.langchain.com/python/langgraph/pregel/_algo/sanitize_untracked_values_in_send) - [`map_debug_tasks()`](https://reference.langchain.com/python/langgraph/pregel/debug/map_debug_tasks) - [`is_multiple_channel_write()`](https://reference.langchain.com/python/langgraph/pregel/debug/is_multiple_channel_write) - [`map_task_result_writes()`](https://reference.langchain.com/python/langgraph/pregel/debug/map_task_result_writes) - [`map_debug_task_results()`](https://reference.langchain.com/python/langgraph/pregel/debug/map_debug_task_results) - [`rm_pregel_keys()`](https://reference.langchain.com/python/langgraph/pregel/debug/rm_pregel_keys) - [`map_debug_checkpoint()`](https://reference.langchain.com/python/langgraph/pregel/debug/map_debug_checkpoint) - [`tasks_w_writes()`](https://reference.langchain.com/python/langgraph/pregel/debug/tasks_w_writes) - [`get_colored_text()`](https://reference.langchain.com/python/langgraph/pregel/debug/get_colored_text) - [`get_bolded_text()`](https://reference.langchain.com/python/langgraph/pregel/debug/get_bolded_text) - [`identifier()`](https://reference.langchain.com/python/langgraph/pregel/_call/identifier) - [`get_runnable_for_entrypoint()`](https://reference.langchain.com/python/langgraph/pregel/_call/get_runnable_for_entrypoint) - [`get_runnable_for_task()`](https://reference.langchain.com/python/langgraph/pregel/_call/get_runnable_for_task) - [`call()`](https://reference.langchain.com/python/langgraph/pregel/_call/call) - [`empty_checkpoint()`](https://reference.langchain.com/python/langgraph/pregel/_checkpoint/empty_checkpoint) - [`create_checkpoint()`](https://reference.langchain.com/python/langgraph/pregel/_checkpoint/create_checkpoint) - [`channels_from_checkpoint()`](https://reference.langchain.com/python/langgraph/pregel/_checkpoint/channels_from_checkpoint) - [`copy_checkpoint()`](https://reference.langchain.com/python/langgraph/pregel/_checkpoint/copy_checkpoint) - [`validate_graph()`](https://reference.langchain.com/python/langgraph/pregel/_validate/validate_graph) - [`validate_keys()`](https://reference.langchain.com/python/langgraph/pregel/_validate/validate_keys) - [`get_new_channel_versions()`](https://reference.langchain.com/python/langgraph/pregel/_utils/get_new_channel_versions) - [`find_subgraph_pregel()`](https://reference.langchain.com/python/langgraph/pregel/_utils/find_subgraph_pregel) - [`get_function_nonlocals()`](https://reference.langchain.com/python/langgraph/pregel/_utils/get_function_nonlocals) - [`is_xxh3_128_hexdigest()`](https://reference.langchain.com/python/langgraph/pregel/_utils/is_xxh3_128_hexdigest) - [`draw_graph()`](https://reference.langchain.com/python/langgraph/pregel/_draw/draw_graph) - [`add_edge()`](https://reference.langchain.com/python/langgraph/pregel/_draw/add_edge) - [`DuplexStream()`](https://reference.langchain.com/python/langgraph/pregel/_loop/DuplexStream) - [`read_channel()`](https://reference.langchain.com/python/langgraph/pregel/_io/read_channel) - [`read_channels()`](https://reference.langchain.com/python/langgraph/pregel/_io/read_channels) - [`map_command()`](https://reference.langchain.com/python/langgraph/pregel/_io/map_command) - [`map_input()`](https://reference.langchain.com/python/langgraph/pregel/_io/map_input) - [`map_output_values()`](https://reference.langchain.com/python/langgraph/pregel/_io/map_output_values) - [`map_output_updates()`](https://reference.langchain.com/python/langgraph/pregel/_io/map_output_updates) - [`gated()`](https://reference.langchain.com/python/langgraph/pregel/_executor/gated) - [`next_tick()`](https://reference.langchain.com/python/langgraph/pregel/_executor/next_tick) - [`run_with_retry()`](https://reference.langchain.com/python/langgraph/pregel/_retry/run_with_retry) - [`arun_with_retry()`](https://reference.langchain.com/python/langgraph/pregel/_retry/arun_with_retry) ## Types - [`Checkpointer`](https://reference.langchain.com/python/langgraph/types/Checkpointer) - [`GraphLifecycleStatus`](https://reference.langchain.com/python/langgraph/callbacks/GraphLifecycleStatus) - [`GraphLifecycleEvent`](https://reference.langchain.com/python/langgraph/callbacks/GraphLifecycleEvent) - [`GraphCallbacks`](https://reference.langchain.com/python/langgraph/callbacks/GraphCallbacks) - [`Messages`](https://reference.langchain.com/python/langgraph/graph/message/Messages) - [`AnyUIMessage`](https://reference.langchain.com/python/langgraph/graph/ui/AnyUIMessage) - [`StateNode`](https://reference.langchain.com/python/langgraph/graph/_node/StateNode) - [`AnyFuture`](https://reference.langchain.com/python/langgraph/_internal/_future/AnyFuture) - [`RunnableLike`](https://reference.langchain.com/python/langgraph/_internal/_runnable/RunnableLike) - [`StateLike`](https://reference.langchain.com/python/langgraph/_internal/_typing/StateLike)