openai/openai-python · error · ValueError

Expected a non-empty value for `thread_id` but received {thr

Error message

Expected a non-empty value for `thread_id` but received {thread_id!r}

What it means

Threads.retrieve (sync) requires a truthy thread_id path parameter for GET /threads/{thread_id}. The SDK raises ValueError client-side instead of issuing a request with an empty path segment. Truthiness check means None and "" (and other falsy values) are rejected.

Source

Thrown at src/openai/resources/beta/threads/threads.py:181

        extra_headers: Headers | None = None,
        extra_query: Query | None = None,
        extra_body: Body | None = None,
        timeout: float | httpx2.Timeout | None | NotGiven = not_given,
    ) -> Thread:
        """
        Retrieves a thread.

        Args:
          extra_headers: Send extra headers

          extra_query: Add additional query parameters to the request

          extra_body: Add additional JSON properties to the request

          timeout: Override the client-level default timeout for this request, in seconds
        """
        if not thread_id:
            raise ValueError(f"Expected a non-empty value for `thread_id` but received {thread_id!r}")
        extra_headers = {"OpenAI-Beta": "assistants=v2", **(extra_headers or {})}
        return self._get(
            path_template("/threads/{thread_id}", thread_id=thread_id),
            options=make_request_options(
                extra_headers=extra_headers,
                extra_query=extra_query,
                extra_body=extra_body,
                timeout=timeout,
                security={"bearer_auth": True},
            ),
            cast_to=Thread,
        )

    @typing_extensions.deprecated("The Assistants API is deprecated in favor of the Responses API")
    def update(
        self,
        thread_id: str,
        *,

View on GitHub (pinned to 9917c6e28e)

Solutions

Pass the real id from the create response: `thread = client.beta.threads.create()` then `client.beta.threads.retrieve(thread.id)`.
If the id comes from storage/env, validate it is a non-empty string before use.
Check for typos in the keyword argument name.

Example fix

# before
thread = client.beta.threads.retrieve(thread_id=os.getenv("THREAD_ID"))
# after
thread_id = os.getenv("THREAD_ID")
if not thread_id:
    raise RuntimeError("THREAD_ID is not set")
thread = client.beta.threads.retrieve(thread_id)

Defensive patterns

Strategy: validation

Validate before calling

if not thread_id:
    raise ValueError("thread_id must be non-empty")
thread = client.beta.threads.retrieve(thread_id)

Type guard

def is_valid_id(value: object) -> bool:
    return isinstance(value, str) and bool(value.strip())

Try / catch

try:
    thread = client.beta.threads.retrieve(thread_id)
except ValueError as e:
    if "thread_id" in str(e):
        log.error("missing thread id"); return None
    raise

Prevention

Store thread.id immediately after create.
Use .get() with required-field checks when reading ids from dicts/env.

When it happens

Trigger: `client.beta.threads.retrieve("")` or `client.beta.threads.retrieve(None)`; also passing a thread id variable that came back None from `client.beta.threads.create()` destructuring or a dict lookup miss.

Common situations: Loading a thread id from config/env/database where the field is absent, or copy-pasting example code without replacing the placeholder `thread_id_abc123`.

Understand the failure class

Background: Missing required parameter errors: what 'X is required' and 'the required X param is missing' mean, and how to fix them — this error's family across 27 libraries.

Related errors

AI-assisted analysis of openai/openai-python@9917c6e28e (2026-08-28). Data as JSON: /api/errors/d33f76119c4d7071. Report an issue: GitHub.