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+---
+name: key-package-lifecycle
+description: Handles key package lifecycle in Marmot apps: creating and publishing packages, tracking kind-443 relay events, marking consumed packages, rotating stale/used packages, and deleting via remove or purge. Use when writing code that calls client.keyPackages, manages invite readiness, replenishes key package supply, or cleans up relay-published packages.
+---
+
+# Key Package Lifecycle
+
+## API Overview
+
+All operations live on `client.keyPackages` (`KeyPackageManager`):
+
+| Method | Effect |
+|---|---|
+| `create(options)` | Generate, store locally, sign and publish kind-443 to relays |
+| `track(event)` | Record an observed kind-443 event; returns `false` if not applicable |
+| `markUsed(ref)` | Flag a package as consumed without deleting it |
+| `rotate(ref, options?)` | Publish kind-5 deletion for old events, create+publish replacement, remove old local material |
+| `remove(ref)` | Local store deletion only — no relay cleanup |
+| `purge(refs)` | Publish kind-5 deletion for all known event IDs, remove local material (bulk-friendly) |
+
+## Core Rules
+
+1. **Never transmit `privatePackage`** — private material stays local only.
+2. **`create()` requires non-empty `relays`** — throws `MissingRelayError` otherwise.
+3. **Track continuously** — feed all incoming kind-443 events to `track()` so publish records stay accurate across devices. This is required for `rotate()` and `purge()` to know which relay event IDs to delete.
+4. **Prefer `rotate()` over `remove()` for published packages** — rotation cleans relays and replenishes supply atomically.
+5. **`used` is rotation debt** — packages marked used should be rotated in the background, not immediately during the join flow.
+6. **Relay deletion is best-effort** — kind-5 events are advisory; do not block UX on confirmation.
+
+## App Workflow
+
+### 1. Bootstrap supply
+
+Publish at least two key packages on onboarding (or when inventory is low) to reduce invite race failures:
+
+```typescript
+await client.keyPackages.create({ relays, isLastResort: true });
+await client.keyPackages.create({ relays, isLastResort: true });
+```
+
+### 2. Ingest relay state
+
+Subscribe to kind `443` for the user's pubkey and feed events to the manager:
+
+```typescript
+for (const event of kind443Events) {
+  await client.keyPackages.track(event); // false = not a valid key package, safe to ignore
+}
+```
+
+### 3. After a group join (consumption)
+
+`MarmotClient` calls `markUsed()` automatically when processing a Welcome. Apps should schedule rotation in the background — do not block the join flow:
+
+```typescript
+// After client.acceptInvite() resolves, rotate in background
+void maintainKeyPackages(client, relays);
+```
+
+### 4. Periodic maintenance
+
+```typescript
+async function maintainKeyPackages(
+  client: MarmotClient,
+  relays: string[],
+): Promise<void> {
+  const entries = await client.keyPackages.list();
+
+  for (const entry of entries) {
+    if (entry.used) {
+      await client.keyPackages.rotate(entry.keyPackageRef);
+    }
+  }
+
+  if ((await client.keyPackages.count()) < 2) {
+    await client.keyPackages.create({ relays, isLastResort: true });
+  }
+}
+```
+
+### 5. User-initiated deletion
+
+- **Delete everywhere** (relay + local): `await client.keyPackages.purge(refs)`
+- **Local only** (package was never published, or relay cleanup already handled): `await client.keyPackages.remove(ref)`
+
+For deletion UX that operates on raw Nostr events (e.g. a relay browser), track the events first so `purge()` has the event IDs:
+
+```typescript
+for (const event of eventsToDelete) {
+  await client.keyPackages.track(event);
+}
+const refs = eventsToDelete.map(getKeyPackageReference).filter(Boolean);
+await client.keyPackages.purge(refs);
+```
+
+## Error Handling
+
+| Error | Thrown by | Resolution |
+|---|---|---|
+| `MissingRelayError` | `create()` | Prompt user for relay configuration |
+| `KeyPackageNotFoundError` | `rotate()` | Refresh local state; fall back to `create()` |
+| `KeyPackageRotatePreconditionError` | `rotate()` | Pass `options.relays` explicitly |
+
+If a package has no tracked `published` events, `rotate()`/`purge()` still removes local material but skips the kind-5 deletion step.