BerriAI/litellm · error · HTTPException

Failed to transform Braintrust response: {str(e)}

Error message

Failed to transform Braintrust response: {str(e)}

What it means

This is the get_error_class factory of LiteLLM's OpenAI Containers transformation: it constructs and raises a BaseLLMException carrying the HTTP status code, the error message, and the response headers extracted from a failed container-API HTTP response. The literal 'error_message' is the parameter name - the actual text comes from the upstream response body. It is LiteLLM's normalization point for non-2xx responses from OpenAI container endpoints (e.g. /v1/containers file operations).

Source

Thrown at cookbook/litellm_proxy_server/braintrust_prompt_wrapper_server.py:233

    except httpx.RequestError as e:
        raise HTTPException(
            status_code=502,
            detail=f"Failed to connect to Braintrust API: {str(e)}",
        )
    except json.JSONDecodeError as e:
        raise HTTPException(
            status_code=502,
            detail=f"Failed to parse Braintrust API response: {str(e)}",
        )

    print(f"braintrust_data: {braintrust_data}")
    # Transform the response
    try:
        transformed_data = transform_braintrust_response(braintrust_data)
        print(f"transformed_data: {transformed_data}")
        return JSONResponse(content=transformed_data)
    except Exception as e:
        raise HTTPException(
            status_code=500,
            detail=f"Failed to transform Braintrust response: {str(e)}",
        )


@app.get("/health")
async def health_check():
    """Health check endpoint."""
    return {"status": "healthy", "service": "braintrust-prompt-wrapper"}


@app.get("/")
async def root():
    """Root endpoint with service information."""
    return {
        "service": "Braintrust Prompt Wrapper for LiteLLM",
        "version": "1.0.0",
        "endpoints": {

View on GitHub (pinned to 6c2dcb801b)

Solutions

1. Catch litellm.exceptions.BaseLLMException (or litellm.APIError) and read .status_code, .message, .headers.
2. 404: verify container_id/file_id exists in the same org/project as the key.
3. 401/403: confirm the key is valid and has container API access.
4. Check .headers for retry-after on 429 and back off accordingly.

Example fix

# before
content = litellm.get_container_file_content(...)

# after
try:
    content = litellm.get_container_file_content(...)
except litellm.exceptions.BaseLLMException as e:
    if e.status_code == 404:
        raise FileNotFoundError(e.message) from e
    raise

def container_file_url_ok(container_id: str, file_id: str) -> bool:
    return container_id.startswith("ctr_") and file_id.startswith("file-")

from litellm.llms.base_llm.chat.transformation import BaseLLMException

def is_container_api_error(e: BaseException) -> bool:
    return isinstance(e, BaseLLMException)

from litellm.exceptions import APIError

try:
    content = litellm.get_container_file_content(...)
except APIError as e:
    sc = getattr(e, "status_code", None)
    if sc == 404:
        raise FileNotFoundError(str(e)) from e
    if sc == 429:
        retry_after = float(getattr(e, "headers", {}).get("retry-after", 5))
        time.sleep(retry_after)
    raise

When it happens

Trigger: Calling litellm container/file APIs (e.g. retrieving binary file content from a container) when OpenAI returns a non-2xx status: 401 invalid key, 404 unknown container or file id, 400 bad request, or 429 rate limiting. The HTTP handler extracts status/body/headers and routes them through this factory to raise BaseLLMException.

Common situations: Using an expired or scoped-down API key that lacks container access; referencing a container_id or file_id from another project/org; preview API changes to the containers endpoints; uploading then immediately downloading files before processing completes.

Related errors

• Error apply_db_fixes: {str(e)}
• Unclassified keys in {PRICES_PATH.name}: {', '.join(unclassi
• No Braintrust API token provided. Pass via Authorization hea
• Braintrust API error: {e.response.text}
• Failed to connect to Braintrust API: {str(e)}

AI-assisted analysis of BerriAI/litellm@6c2dcb801b (2026-08-15). Data as JSON: /api/errors/a8bb43a6cf7a0f7b. Report an issue: GitHub.