fromTimestamp in api/public/v2/scores not working as expected

[kaikiat]

url = f"{settings.langfuse_host}/api/public/v2/scores"
params = {
    'page': page,
    'limit': limit,
    'name': 'user_feedback',
    'operator': '<',
    'value': upper_limit,
    'dataType': 'NUMERIC',
    'source': 'API',
    'fromTimestamp': datetime(2025, 11, 1, tzinfo=timezone.utc).isoformat()
}

After running this command, I am still getting scores that are created before that timestamp i.e

{'id': 'sample-id', 'timestamp': '2025-09-15T06:03:01.782Z', 'projectId': 'sample-project-id', 'environment': 'default', 'name': 'user_feedback', 'source': 'API', 'authorUserId': None, 'comment': '{"reasoning_for_error": [{"score": 1.0, "comment": ""}, {"score": 1.0, "comment": ""}, {"score": 1.0, "comment": ""}, {"score": 1.0, "comment": ""}], "possible_ways_to_resolve": [{"score": 1.0, "comment": ""}, {"score": 0.0, "comment": "test"}, {"score": 1.0, "comment": ""}, {"score": 1.0, "comment": ""}], "references_to_help_developer": [{"score": 1.0, "comment": ""}, {"score": 1.0, "comment": ""}, {"score": 1.0, "comment": ""}, {"score": 1.0, "comment": ""}]}', 'metadata': {}, 'configId': None, 'createdAt': '2025-09-15T06:03:03.000Z', 'updatedAt': '2025-09-15T06:03:07.685Z', 'queueId': None, 'traceId': 'sample-trace-ed', 'observationId': None, 'sessionId': None, 'datasetRunId': None, 'value': 0.9166666666666666, 'stringValue': None, 'dataType': 'NUMERIC', 'trace': {'userId': 'sample-user', 'tags': [], 'environment': 'default'}}

I am on Langfuse v3.117.2

[inkeep-ai-assistant[bot]]

The fromTimestamp parameter in the /api/public/v2/scores endpoint filters scores based on when they were created, not their timestamp field(1).

According to the API documentation, fromTimestamp is described as: "Optional filter to only include scores created on or after a certain datetime (ISO 8601)"(1). This means it filters on the createdAt field, not the timestamp field.

In your example, the score has:

• timestamp: 2025-09-15T06:03:01.782Z
• createdAt: 2025-09-15T06:03:03.000Z

Since you're filtering with fromTimestamp set to 2025-11-01, and the score's createdAt is 2025-09-15, this score should not appear in the results. This appears to be a bug.

To work around this issue, you could:

1. Filter the results client-side based on the createdAt field after receiving the API response
2. Use the Metrics API endpoint (/api/public/metrics) which may provide more reliable filtering options(2)(3)

You may want to report this as a bug to the Langfuse team, as the filtering behavior doesn't match the documented specification(1).

📚 Sources:

1. GET /api/public/v2/scores
2. Metrics API
3. GET /api/public/metrics

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