{"record":{"id":"9e5204213dfeadfd","repo":"langchain-ai/langgraph","slug":"emptychannelerror-9e5204","errorCode":null,"errorMessage":"EmptyChannelError","messagePattern":"EmptyChannelError","errorType":"exception","errorClass":"EmptyChannelError","httpStatus":null,"severity":"error","filePath":"libs/langgraph/langgraph/channels/binop.py","lineNumber":148,"sourceCode":"        for value in values:\n            is_overwrite, overwrite_value = _get_overwrite(value)\n            if is_overwrite:\n                if seen_overwrite:\n                    msg = create_error_message(\n                        message=\"Can receive only one Overwrite value per super-step.\",\n                        error_code=ErrorCode.INVALID_CONCURRENT_GRAPH_UPDATE,\n                    )\n                    raise InvalidUpdateError(msg)\n                self.value = overwrite_value\n                seen_overwrite = True\n                continue\n            if not seen_overwrite:\n                self.value = self.operator(self.value, value)\n        return True\n\n    def get(self) -> Value:\n        if self.value is MISSING:\n            raise EmptyChannelError()\n        return self.value\n\n    def is_available(self) -> bool:\n        return self.value is not MISSING\n\n    def checkpoint(self) -> Value:\n        return self.value\n","sourceCodeStart":130,"sourceCodeEnd":156,"githubUrl":"https://github.com/langchain-ai/langgraph/blob/38031739e551638e373fb553453256c23feeb41f/libs/langgraph/langgraph/channels/binop.py#L130-L156","documentation":"Error \"EmptyChannelError\" thrown in langchain-ai/langgraph.","triggerScenarios":"Thrown at libs/langgraph/langgraph/channels/binop.py:148 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"}