langchain-ai/langgraph · error · InvalidUpdateError

Cannot apply multiple updates when clearing state

Error message

Cannot apply multiple updates when clearing state

What it means

Error "Cannot apply multiple updates when clearing state" thrown in langchain-ai/langgraph.

Source

Thrown at libs/langgraph/langgraph/pregel/main.py:1680

                },
            )
            if saved:
                checkpoint_config = patch_configurable(config, saved.config[CONF])
            channels, managed = channels_from_checkpoint(
                self.channels,
                checkpoint,
                saver=self.checkpointer
                if saved is not None
                and isinstance(self.checkpointer, BaseCheckpointSaver)
                else None,
                config=saved.config if saved is not None else None,
            )
            values, as_node = updates[0][:2]

            # no values as END, just clear all tasks
            if values is None and as_node == END:
                if len(updates) > 1:
                    raise InvalidUpdateError(
                        "Cannot apply multiple updates when clearing state"
                    )

                if saved is not None:
                    # tasks for this checkpoint
                    next_tasks = prepare_next_tasks(
                        checkpoint,
                        saved.pending_writes or [],
                        self.nodes,
                        channels,
                        managed,
                        saved.config,
                        step + 1,
                        step + 3,
                        for_execution=True,
                        store=self.store,
                        checkpointer=checkpointer,
                        manager=None,

View on GitHub (pinned to 38031739e5)

When it happens

Trigger: Thrown at libs/langgraph/langgraph/pregel/main.py:1680 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of langchain-ai/langgraph@38031739e5 (2026-08-26). Data as JSON: /api/errors/5518dfa1bb23082c. Report an issue: GitHub.