BerriAI/litellm · error · Exception

Vector store index not found for {collection_name}

Error message

Vector store index not found for {collection_name}

What it means

After authorization, the handler looks up the previously validated collection name in litellm.vector_store_index_registry.get_vector_store_index_by_name() and gets None — the index entry disappeared between the is_vector_store_index check and the fetch (e.g. concurrent deletion or config reload). Thrown as a bare Exception, not an HTTPException.

Source

Thrown at litellm/proxy/pass_through_endpoints/llm_passthrough_endpoints.py:494

            status_code=400,
            detail=f"Collection {collection_name} is not a litellm managed vector store index. Only litellm managed vector store indexes are supported.",
        )

    is_allowed_to_call_vector_store_endpoint(
        index_name=collection_name,
        provider=LlmProviders.MILVUS,
        request=request,
        user_api_key_dict=user_api_key_dict,
    )
    # get the vector store name from index registry

    index_object: Final = (
        (litellm.vector_store_index_registry.get_vector_store_index_by_name(vector_store_index_name=collection_name))
        if litellm.vector_store_index_registry is not None
        else None
    )
    if index_object is None:
        raise Exception(f"Vector store index not found for {collection_name}")

    vector_store_name: Final = index_object.litellm_params.vector_store_name
    vector_store_index: Final = index_object.litellm_params.vector_store_index

    request_body["collectionName"] = vector_store_index

    # Update the request object with the modified collection name
    _safe_set_request_parsed_body(request, request_body)

    vector_store: Final = litellm.vector_store_registry.get_litellm_managed_vector_store_from_registry_by_name(
        vector_store_name=vector_store_name
    )
    if vector_store is None:
        raise Exception(f"Vector store not found for {vector_store_name}")
    await assert_user_can_access_vector_store(
        vector_store=vector_store,
        user_api_key_dict=user_api_key_dict,
    )

View on GitHub (pinned to 77b7c6c40c)

Solutions

1. Create a vector store index for the given collection_name via the proxy's vector store API.
2. Check for typos in collection_name; list existing indexes to confirm the correct name.

When it happens

Trigger: Thrown at litellm/proxy/pass_through_endpoints/llm_passthrough_endpoints.py:494 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of BerriAI/litellm@77b7c6c40c (2026-08-18). Data as JSON: /api/errors/1d03a4981cfe1a8c. Report an issue: GitHub.