{"record":{"id":"d445a21f7a6e618b","repo":"langchain-ai/langgraph","slug":"no-checkpointer-set","errorCode":null,"errorMessage":"No checkpointer set","messagePattern":"No checkpointer set","errorType":"exception","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"libs/langgraph/langgraph/pregel/main.py","lineNumber":1402,"sourceCode":"            patch_checkpoint_map(saved.config, saved.metadata),\n            saved.metadata,\n            saved.checkpoint[\"ts\"],\n            patch_checkpoint_map(saved.parent_config, saved.metadata),\n            tasks_with_writes,\n            tuple([i for task in tasks_with_writes for i in task.interrupts]),\n        )\n\n    def get_state(\n        self, config: RunnableConfig, *, subgraphs: bool = False\n    ) -> StateSnapshot:\n        \"\"\"Get the current state of the graph.\"\"\"\n        checkpointer: BaseCheckpointSaver | None = ensure_config(config)[CONF].get(\n            CONFIG_KEY_CHECKPOINTER, self.checkpointer\n        )\n        if isinstance(checkpointer, BaseCheckpointSaver):\n            checkpointer = self._apply_checkpointer_allowlist(checkpointer)\n        if not checkpointer:\n            raise ValueError(\"No checkpointer set\")\n\n        if (\n            checkpoint_ns := config[CONF].get(CONFIG_KEY_CHECKPOINT_NS, \"\")\n        ) and CONFIG_KEY_CHECKPOINTER not in config[CONF]:\n            # remove task_ids from checkpoint_ns\n            recast = recast_checkpoint_ns(checkpoint_ns)\n            # find the subgraph with the matching name\n            for _, pregel in self.get_subgraphs(namespace=recast, recurse=True):\n                return pregel.get_state(\n                    patch_configurable(config, {CONFIG_KEY_CHECKPOINTER: checkpointer}),\n                    subgraphs=subgraphs,\n                )\n            else:\n                raise ValueError(f\"Subgraph {recast} not found\")\n\n        config = merge_configs(self.config, config) if self.config else config\n        if self.checkpointer is True:\n            ns = cast(str, config[CONF][CONFIG_KEY_CHECKPOINT_NS])","sourceCodeStart":1384,"sourceCodeEnd":1420,"githubUrl":"https://github.com/langchain-ai/langgraph/blob/38031739e551638e373fb553453256c23feeb41f/libs/langgraph/langgraph/pregel/main.py#L1384-L1420","documentation":"Error \"No checkpointer set\" thrown in langchain-ai/langgraph.","triggerScenarios":"Thrown at libs/langgraph/langgraph/pregel/main.py:1402 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"38031739e551638e373fb553453256c23feeb41f","analyzedAt":"2026-08-26T18:02:49.312Z","schemaVersion":2},"datasetVersion":"2026-08-26T21:11:00.512Z"}