Scores added via API not displaying in UI - Braintrust

Applies to:

• Plan - Any
• Deployment - Braintrust-hosted
• Use case - Programmatically adding scores to existing traces via API

Summary

Issue: Scores submitted via the Braintrust feedback API do not appear in the UI for existing traces, and instead create new trace entries with the provided span_id and root_span_id.
Cause: The span_id used in the API payload does not match the actual id property in the raw trace data.
Resolution: Use the correct id from the raw span data when submitting scores via the feedback API.

Resolution Steps

Step 1: Get the correct span ID

Navigate to the trace in the Braintrust UI and click the “Raw span and trace data” button to view the underlying JSON.

Step 2: Identify the ID field

Locate the id property in the raw trace data JSON - this is the value you need to use in your API calls.

Step 3: Update your API payload

Use the id from the raw data as the span_id in your feedback API payload:

payload = {
    "events": [\
        {\
            "span_id": "correct-id-from-raw-data",\
            "root_span_id": "correct-id-from-raw-data",\
            "scores": 0.0,\
            "metadata": feedback_update["metadata"],\
            "_is_merge": True,\
            "_merge_paths": merge_paths,\
        }\
    ]
}

Step 4: Verify the score appears

Refresh the trace view in the UI to confirm the score is now attached to the existing trace instead of creating a new one.