microsoft/autogen · error · ValueError

task_done() called too many times

Error message

task_done() called too many times

What it means

Error "task_done() called too many times" thrown in microsoft/autogen.

Source

Thrown at python/packages/autogen-core/src/autogen_core/_queue.py:222

    def task_done(self) -> None:
        """Indicate that a formerly enqueued task is complete.

        Used by queue consumers. For each get() used to fetch a task,
        a subsequent call to task_done() tells the queue that the processing
        on the task is complete.

        If a join() is currently blocking, it will resume when all items have
        been processed (meaning that a task_done() call was received for every
        item that had been put() into the queue).

        shutdown(immediate=True) calls task_done() for each remaining item in
        the queue.

        Raises ValueError if called more times than there were items placed in
        the queue.
        """
        if self._unfinished_tasks <= 0:
            raise ValueError("task_done() called too many times")
        self._unfinished_tasks -= 1
        if self._unfinished_tasks == 0:
            self._finished.set()

    async def join(self) -> None:
        """Block until all items in the queue have been gotten and processed.

        The count of unfinished tasks goes up whenever an item is added to the
        queue. The count goes down whenever a consumer calls task_done() to
        indicate that the item was retrieved and all work on it is complete.
        When the count of unfinished tasks drops to zero, join() unblocks.
        """
        if self._unfinished_tasks > 0:
            await self._finished.wait()

    def shutdown(self, immediate: bool = False) -> None:
        """Shut-down the queue, making queue gets and puts raise QueueShutDown.

View on GitHub (pinned to 027ecf0a37)

Solutions

  1. Pair each task_done() with a prior get()

Example fix

Call task_done() exactly once per dequeued item

When it happens

Trigger: Thrown at python/packages/autogen-core/src/autogen_core/_queue.py:222 when the library encounters an invalid state.

Common situations: See trigger scenarios.


AI-assisted analysis of microsoft/autogen@027ecf0a37 (2026-08-15). Data as JSON: /api/errors/98e8f03b8cac5e32. Report an issue: GitHub.