Troubleshooting
| Symptom | Cause | Fix |
|---|---|---|
/predict returns 503 |
no version promoted yet | promote one in the dashboard |
| Client shows unhealthy | 3 consecutive schema mismatches | check the events feed: it names the columns that didn't match |
| Training never starts | no schedule, or the min-client gate | the events feed records a window_skipped with the connected/required counts |
| Client never appears | enrollment key already used | keys are single-use; regenerate the kit |
The events feed
The federation's events feed is the first place to look. It records every window opened, skipped, trained and closed, and every schema mismatch, with the reason.