# Phase 04: SMS Gateway (Credits + Queue)

**Status:** ✅ Complete — 2026-03-15

## Goal
Schools submit SMS jobs via Hub; Hub sends via Semaphore; credits deducted per message.
Full SMS dashboard for super admin with stats, charts, job table, Semaphore health.

## Completed

### 4-01: Backend stats + retry + health + trigger
- `GET /api/sms/stats` — aggregate totals, daily chart (N days), school breakdown
- `POST /api/sms/jobs/{id}/retry` — reset failed/cancelled job to pending
- `GET /api/sms/health` — Semaphore connectivity + credit balance
- `POST /api/sms/trigger-queue` — manual Celery task trigger (admin)
- `api.ts`: getSmsStats, retrySmsJob, getSmsHealth, triggerSmsQueue

### 4-02: SmsPage full dashboard
- Semaphore health badge (green/red, shows balance)
- Process Queue button (fires trigger-queue)
- KPI row: Total, Sent, Failed, Pending, Delivery Rate %, period picker 7/30/90d
- Volume bar chart (daily sent vs failed, hover tooltips)
- School breakdown panel (top 10, sent/total ratio bars)
- Jobs table: status + school + phone filters, error message on failed rows,
  Retry button, retry count, pagination