Use this skill to perform memory housekeeping. Trigger if the user says "housekeeping", "clean up memory", "prune memory", "archive old data", or similar maintenance requests.

## 0. Orientation (run FIRST, before any file reads)

Use these shell commands to scope your work before reading files:

```bash
# What changed since last run? Focus here first.
find memory/ -type f -name "*.md" -mtime -1 | sort

# Quick entry counts for archival threshold checks (>50 = archive)
# Add paths for any domain observations files that exist
grep -c "^- " memory/cog-meta/self-observations.md memory/personal/observations.md memory/*/observations.md memory/*/*/observations.md 2>/dev/null

# Completed action items count (>10 = archive)
grep -c "^\- \[x\]" memory/personal/action-items.md memory/*/action-items.md memory/*/*/action-items.md 2>/dev/null
```

Only read files that need work based on these results. Skip unchanged files.

## 1. Garbage Collect Memory

Review and archive stale data per CLAUDE.md glacier rules. All glacier files must have YAML frontmatter.

**Observations — archive by primary tag:**
- If any `observations.md` has >50 entries, group oldest entries by primary tag and move to `memory/glacier/{domain}/observations-{tag}.md`
- If `memory/cog-meta/self-observations.md` has >50 entries, group by primary tag → `memory/glacier/cog-meta/observations-{tag}.md`

**Other files — standard rules:**
- If any `action-items.md` has >10 completed items, move to `memory/glacier/{domain}/action-items-done.md`
- Apply same logic for all domains listed in `memory/domains.yml`
- If `memory/cog-meta/improvements.md` has >10 implemented items, move to `memory/glacier/cog-meta/improvements-done-{YYYY}.md`

## 2. Prune Hot Memory (rule-based)

Keep ALL hot-memory.md files under 50 lines. Relevance judgment (promote/demote) is /reflect's job — you apply structural rules:

**Files to check:**
Read `memory/domains.yml` to discover all active domains. Check `hot-memory.md` for each domain, plus the cross-domain `memory/hot-memory.md`.

**Pruning priority (trim in this order):**
1. **Resolved items** — anything with ~~strikethrough~~, "DONE", "RESOLVED"
2. **Past events** — entries about dates that have already occurred
3. **SSOT violations** — same fact in hot-memory AND the canonical file (entities, action-items, etc.). Keep in canonical file, replace hot-memory copy with `[[link]]` or remove
4. **Stale entries** — items not referenced in 14+ days
5. **Low-signal entries** — FYI items with no action or deadline

**Where trimmed entries go:**
- Entries with lasting value → append to domain's `observations.md`
- Entries that are purely historical → let them go
- Never silently delete — always move or note removal in debrief

## 3. Surface Opportunities & Accountability

Review all `action-items.md` files across every domain:
- **Stale items** (open >2 weeks): list with age and suggested next action
- **Dormant domains**: if any domain has 0 new observations in >4 weeks, flag
- **Health escalation**: items open >6 months get flagged with urgency label
- **Birthday prep**: if any birthday in entities.md is <2 weeks away, pull interests and suggest ideas

Be direct. Don't just report — recommend specific actions.

## 4. Rebuild Glacier Index

Scan all `memory/glacier/**/*.md` files. Extract YAML frontmatter. Write results to `memory/glacier/index.md`:

```
# Glacier Index
<!-- Auto-generated by housekeeping. Do not edit. -->
<!-- Last updated: YYYY-MM-DD -->

| File | Domain | Type | Tags | Date Range | Entries | Summary |
|------|--------|------|------|------------|---------|---------|
```

## 5. Link Audit (discover missing links)

For each non-glacier memory file:
1. **Entity mentions**: Scan for names matching `### <Name>` headers in entities.md — add `[[links]]` if missing
2. **Cross-domain references**: If a file mentions a topic from another domain, add a cross-domain link
3. **Action item references**: If an observation references a task, link it

Only add links where the reference is substantive.

## 5b. Entity Registry Format Enforcement

Scan all `entities.md` files for registry format compliance:

1. **3-line max**: Any `### entry` with >3 content lines should be compressed. If the entry has an associated detail file (`→ [[link]]`), compress to: name/relationship, pipe-separated key facts, status+link. If no detail file exists and entry is >5 lines, flag as a promotion candidate (suggest creating a thread file).
2. **Glacier candidates**: Entries with `status: inactive` or `last:` date >6 months ago → move to `glacier/{domain}/entities-inactive.md` (leave a stub with archived comment).
3. **Missing metadata**: Flag entries missing `status:` or `last:` fields.

## 5c. Temporal Fact Maintenance

Scan all `entities.md` files for `(until YYYY-MM)` markers with past dates:
1. If the line has no ~~strikethrough~~, add it
2. If already struck through, move to a `## Historical` subsection at the bottom of that entity's block (create the subsection if absent)
3. Report moved facts in the debrief

## 6. Rebuild Link Index

Scan all memory files (excluding `glacier/`) for `[[wiki-links]]`. For each link, record: target → source.

Rewrite `memory/link-index.md`:

```markdown
# Memory Link Index
<!-- Auto-generated by housekeeping. Do not edit. -->
<!-- Last updated: YYYY-MM-DD -->

| Target | Linked from |
|--------|-------------|
| `personal/entities` | `personal/observations`, `personal/hot-memory` |
```

Rules:
- Only include targets with at least one inbound link
- Combine multiple sources per target on one row (comma-separated)
- Exclude glacier files from both source and target

## 7. Write Briefing Bridge

Write key findings to `memory/cog-meta/briefing-bridge.md` so foresight can pick them up. Overwrite the file each run.

**SSOT rule**: Every line in the bridge must include a `[[source]]` link to its canonical file. The bridge summarizes and links — it NEVER introduces original facts.

```markdown
# Briefing Bridge
<!-- Auto-generated by housekeeping. Consumed by foresight. -->
<!-- Last updated: YYYY-MM-DD -->

## Stale Items (>2 weeks)
- <item> — <age> — suggested action: <action>
- **Compression rule**: Items stale >4 weeks — group by domain as a single line

## Birthday Prep
- <name> birthday in <N> days — interests: <from entities> — gift ideas: <suggestions>

## Dormant Domains
- <domain> — last activity: <date> — recommendation: <shelf/reactivate/shut down>

## Health Escalation
- <item> — open <N> months — urgency: <high/medium>
```

Only include sections that have content. Empty sections should be omitted.

## 8. L0 Header Maintenance

Check all active memory files for missing `<!-- L0: ... -->` headers. If a file is missing its L0:
- Read the file content, write a one-line summary (max 80 chars)
- Add on the line after the `# Title`

L0 headers are the first tier of the retrieval protocol — they let any skill scan what a file contains before deciding to read it.

## 9. Rebuild Domain Indexes

Regenerate `INDEX.md` for each domain directory. These files power the memory router — the system prompt only shows a light domain table; the model reads INDEX.md on demand to find specific files.

**For each domain** (scan `memory/` for directories, skip `glacier/`):
1. List all `.md` files in the domain (exclude `INDEX.md`, `hot-memory.md`, and empty files)
2. Extract the L0 summary from each file (same logic as step 8)
3. Count total files
4. Write `memory/{domain}/INDEX.md`:

```markdown
# {Domain} Index
<!-- L0: {domain summary} — {N} files -->
<!-- Auto-generated by housekeeping. Do not edit. -->
<!-- Last updated: YYYY-MM-DD -->

- **{filename}** — {L0 summary}
- **{filename}** — {L0 summary}
...
```

- Sort entries alphabetically by filename
- Domain summary: use the `label` from `memory/domains.yml` for the matching domain
- If a file has no L0, list it as just `**{filename}**` (no summary)

## 10. Compose Debrief

Summarize everything done:
- What was archived/pruned
- Upcoming events flagged
- Action items surfaced
- Links added

Keep it concise but informative.