Cost tracking shows $0.00 for some completed jobs #43
Description
Bug
Several jobs that completed all phases show actual_cost = 0.0, while similar jobs show accurate costs. This suggests the Langfuse cost tracking integration is inconsistent.
Examples
| Job | File | Phases | Cost | Notes |
|---|---|---|---|---|
| 1 | 2SOS2026HD.srt (74 min) |
All + timestamp | $0.0239 | Suspiciously low for a long transcript |
| 4 | 9SOT2026HD.srt |
All + timestamp | $0.5153 | Reasonable |
| 17 | TLB_QWERTY.txt |
All | $0.0000 | Zero despite completion |
| 18 | test_transcript.txt |
All | $0.0000 | Zero despite completion |
Possible Causes
- Langfuse callback not firing for certain tier/model combinations
- Cost not being aggregated back to the job record after phase completion
- Race condition between phase completion and cost write-back
- Tier 0 ("cheapskate") models may not have pricing configured in Langfuse
Location
Cost tracking in api/services/llm.py and aggregation in api/services/worker.py