Usage — total data dir, Corestore, memory rings, warm HyperDB sample

Hot memory — 15m → 24h (or custom points)
Warm memory — downsampled ring + samples-per-bucket
Disk history — auto-rotate by age (1 day → 1 year, forever, or custom days)
Soft disk budget + max warm points
Auto prune on a configurable hour interval
Dry-run prune / Prune now / Save to agent (admin role)

docs/PROTOCOL.md

@@ -108,9 +108,18 @@ Journal is **enabled by default** on Linux (`PEARDATA_JOURNAL=0` to disable). In
 | Method | Role | Known jobs |
 |--------|------|------------|
 | `listJobs` | viewer | — |
-| `runJob` | operator | `collectOnce`, `snapshot`, `gcBuffers` |
+| `runJob` | operator | `collectOnce`, `snapshot`, `gcBuffers` (prune) |
 | `cancelJob` | operator | By job id |
 
+### Data Manager (retention / storage)
+
+| Method | Role | Notes |
+|--------|------|-------|
+| `getStorageInfo` | viewer | Disk usage, memory rings, warm sample stats, effective retention |
+| `getRetentionConfig` | viewer | Current policy (`retention.json`) |
+| `setRetentionConfig` | admin | Update hot/warm rings, age rotate, disk budget, auto-prune |
+| `pruneHistory` | admin | `{ dryRun?, beforeMs? }` — delete warm points past retention |
+
 ### HyperDB / peer links
 
 | Method | Role | Notes |