# Quota Management

## User Perspective
The Quota History page (`/quota-history`) shows YouTube API quota usage over time. Each sync or playlist operation is logged. Entries are grouped by action (e.g. all API calls for a single video sync appear as one row) with the total quota cost shown.

The display shows:
- Video title + YouTube video ID
- Action type (video_sync, playlist_add, etc.)
- Units consumed
- Time of operation
- Expandable detail rows

## Developer Perspective

### Quota Budget
YouTube imposes a **10,000 unit daily quota** that resets at midnight Pacific Time. Key costs:
- `videos.update` — 50 units
- `videos.list` — 1 unit
- Playlist operations — varies

### QuotaService
- `canSpend(units: number)` — returns true if spending is allowed
- `spend(units, operation, meta)` — logs usage to `QuotaLog`

All YouTube API writes must call `canSpend()` before proceeding and `spend()` after. This is enforced in the `youtube-sync` processor.

### QuotaLog Fields
`datePt` stores the date in Pacific Time (for correct daily boundary). `actionId` groups related log entries from one user action (e.g. one video sync). The frontend clusters entries with the same `videoId` within 60 seconds for display.

## Related
- [[10 - Quota API]]