HKUDS/DeepTutor · error · PathBindingError

Mastery path {target!r} is being tutored in another conversa

Error message

Mastery path {target!r} is being tutored in another conversation right now (session {exc.lease.session_id!r}). Try again once that turn finishes.

What it means

Error "Mastery path {target!r} is being tutored in another conversation right now (session {exc.lease.session_id!r}). Try again once that turn finishes." thrown in HKUDS/DeepTutor.

Source

Thrown at deeptutor/capabilities/mastery/binding.py:80

    if require_existing and not await asyncio.to_thread(store.exists, target):
        raise PathBindingError(
            f"No mastery path {path_id!r} exists. Call mastery_paths for the "
            "ids you can switch to, or mastery_build to create one here."
        )

    # One lease row per turn: the old one has to go before the new one can be
    # taken, and both are scoped to this turn so a concurrent conversation on
    # either path is never disturbed.
    released = await asyncio.to_thread(store.release_leases_for_turn, turn_id)
    try:
        await asyncio.to_thread(store.acquire_path_lease, target, session_id, turn_id)
    except PathLeaseConflictError as exc:
        # Put the learner back where they were rather than stranding the turn
        # with no lease at all.
        if released and released != target:
            with contextlib.suppress(Exception):
                await asyncio.to_thread(store.acquire_path_lease, released, session_id, turn_id)
        raise PathBindingError(
            f"Mastery path {target!r} is being tutored in another conversation "
            f"right now (session {exc.lease.session_id!r}). Try again once that "
            "turn finishes."
        ) from exc

    _apply(bind_turn, target)
    await _remember_on_session(session_id, target)
    return target


async def leave_active_path(
    *,
    session_id: str,
    turn_id: str,
    bind_turn: PathBinder | None,
) -> str:
    """Detach the conversation from any named path.

View on GitHub (pinned to 3e82f13042)

When it happens

Trigger: Thrown at deeptutor/capabilities/mastery/binding.py:80 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of HKUDS/DeepTutor@3e82f13042 (2026-08-27). Data as JSON: /api/errors/0c1d4833bee4bfef. Report an issue: GitHub.