langchain-ai/deepagents · error · TypeError

thread_id path parameter must be non-empty.

Error message

thread_id path parameter must be non-empty.

What it means

_execute_offload requires the thread_id path parameter to be truthy (a non-empty identifier) before it acquires the thread lock and talks to the thread server. An empty string, None, or other falsy thread_id means the caller never resolved a workspace/thread binding, so the operation cannot be addressed and is rejected with a TypeError.

Source

Thrown at libs/code/deepagents_code/offload_api.py:877

    Args:
        thread_id: LangGraph thread to compact.
        operation_id: Opaque client-generated attempt identity.
        context: Runtime model and hooks context.
        hook_responses: Accumulated hook replies keyed by invocation id.

    Returns:
        A complete result or a hook request that must be answered.

    Raises:
        TypeError: If `thread_id` is empty.
        _OffloadConflictError: If the thread is active or changes before commit.
        _OffloadUnavailableError: If the server runtime cannot be built, so no
            operation can run.
        RuntimeError: If the operation attempts to write conversation messages.
    """
    if not thread_id:
        msg = "thread_id path parameter must be non-empty."
        raise TypeError(msg)
    client = _thread_client()
    async with _thread_lock(thread_id):
        await _require_idle_thread(client, thread_id)
        before = await client.threads.get_state(thread_id)
        if before.get("next") or before.get("tasks") or before.get("interrupts"):
            msg = "Cannot offload a thread with pending graph work."
            raise _OffloadConflictError(msg)

        state = _hydrate_state(before.get("values"))
        if not state.get("messages"):
            # An empty thread is "nothing to offload", not a failure. Answer it
            # here: `_checkpoint_id` below rejects a thread with no checkpoint,
            # so without this the graceful `empty` branch in
            # `OffloadOperation.execute` is unreachable over HTTP and the user
            # is told the operation failed.
            return {
                "status": "complete",
                "result": unchanged_offload_result("empty", messages=0, tokens=0),

View on GitHub (pinned to a1af029e6e)

Solutions

1. Resolve/validate the binding before calling: create or fetch the thread and pass its real id.
2. Guard the call: if not thread_id: raise a clear configuration error or initialize the workspace first.
3. Check your config/env for the thread/workspace id — an unset variable often degrades to an empty string rather than None.
4. Strip and re-check: thread_id = (raw or '').strip() and fail fast if empty.

Example fix

// before
await offload(thread_id=os.environ.get("THREAD_ID", ""), payload=payload)
// after
thread_id = os.environ.get("THREAD_ID", "").strip()
if not thread_id:
    raise ValueError("THREAD_ID is not configured; bind a workspace thread first")
await offload(thread_id=thread_id, payload=payload)

def ensure_thread_id(thread_id):
    if not thread_id or not isinstance(thread_id, str) or not thread_id.strip():
        raise ValueError("thread_id must be resolved (non-empty) before offload; bind a workspace thread first")
    return thread_id.strip()

def has_thread_id(thread_id) -> bool:
    return isinstance(thread_id, str) and bool(thread_id.strip())

try:
    state = await offload(thread_id, payload)
except TypeError as exc:
    if "thread_id path parameter" in str(exc):
        raise RuntimeError("No thread bound to this session; complete workspace/thread binding first") from exc
    raise

When it happens

Trigger: Calling offload() with thread_id='', thread_id=None, or an unvalidated variable that resolved to empty because no workspace/thread binding was set (see test_missing_workspace_binding_is_rejected / test_missing_workspace_context_is_rejected).

Common situations: A fresh session where the workspace binding step was skipped, an env/config key for the thread id missing so the default resolved to '', stripping whitespace in config leaving an empty value, or calling offload before thread creation.

Understand the failure class

Background: "Missing required field" and "field is required" errors: why libraries reject payloads that omit mandatory fields — this error's family across 20 libraries.

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AI-assisted analysis of langchain-ai/deepagents@a1af029e6e (2026-08-29). Data as JSON: /api/errors/68075b26babdf6b3. Report an issue: GitHub.