/sunset-review

name: sunset-review
description: >
  Use this skill when the user wants to identify unused, near-zero-use, or stale skills/agents/commands in
  the plugin surface so they can be demoted or retired. Combines agent-dispatch telemetry (start-events
  only) with static reference scanning, classifies every surface item into Active / Investigate / Demote /
  Retire, and emits a Markdown report plus JSON sidecar. NEVER auto-deletes — surfaces candidates for
  human decision. Quarterly cadence. <example>Context: The plugin surface has grown and the maintainer
  wants to prune dead weight. user: "/sunset-review" assistant: "Running the sunset walk — classifying
  skills, agents, and commands by usage telemetry + static refs, grouped by Retire / Demote / Investigate
  / Active. No item is deleted automatically; I'll surface Retire/Demote candidates for your decision."
  <commentary>The user wants a usage-driven prune candidate list; this skill runs the read-only walker,
  presents grouped verdicts, and writes a sidecar — it never deletes.</commentary></example>
user-invocable: true
argument-hint: "[--kind skill|agent|command] [--window-days N]"
model: inherit
color: amber

Sunset Review Skill

Identify which skills, agents, and commands in the plugin surface are still earning their keep, and which are candidates to **Demote** (downgrade docs/tier) or **Retire** (remove). The skill is advisory: it produces a ranked candidate list and a sidecar artifact. **It never deletes anything.**

Invocation

Parse `$ARGUMENTS` before Phase 1. Two optional flags narrow the scope; anything else is ignored.

| Flag | Behavior | |---|---| | `--kind skill\|agent\|command` | Limits the walk to one surface kind — passed straight through to the walker. | | `--window-days N` | Overrides the default 90-day dispatch window resolved in Phase 1. |

`/harness-audit` answers a third question — "is session-orchestrator installed correctly?" (plugin health) — and is not this skill.

Why this is a distinct skill (not /repo-audit)

`/repo-audit` answers "does this repo match the ecosystem baseline?" — a pass/fail compliance check. `/sunset-review` answers a different question — "which parts of OUR surface are unused?" — with different inputs (dispatch telemetry + static ref scanning), a different cadence (quarterly, not per-session), and a different output (prune candidates, not compliance status). Folding it into repo-audit would muddy both.

Core data contract (read this before trusting any verdict)

The walker — `scripts/lib/sunset/walker.mjs` — is **read-only** and was built against the following grep-verified telemetry facts. Do not override them:

1. **Both agent dispatch and skill-invocation telemetry are now consumed.** `subagents.jsonl` records agent dispatches; `skill-invocations.jsonl` records Skill tool selection events (L1 telemetry, epic #645). Agents are assessed by agent-dispatch counts; **skills are assessed by real selection counts from `skill-invocations.jsonl`, supplemented by static reference scanning.** Commands still have no invocation telemetry and are assessed by static reference scanning only. Skills with zero invocations in the window receive a zero-count (not null), so the low-coverage guard still applies and can downgrade Retire → Investigate when the telemetry window is short. 2. **Only `event === "start"` records count.** `agent_type` is `null` on every `stop` event. A stop event must never mark an agent cold. The walker filters to start events. 3. **Telemetry only spans ~18 days.** A 90-day window cannot be satisfied by 18 days of data. **MANDATORY GUARDRAIL:** when `coverageDays < windowDays`, every `Retire` verdict is downgraded to `Investigate` and `meta.lowConfidence` is set true. Retiring on sub-window data is unsafe — treat any cold finding as "investigate", not "delete". 4. **Zero ≠ near-zero.** A never-dispatched agent (e.g. `memory-proposal-collector`, a by-design reference doc) is a Retire candidate; a once-dispatched agent (`db-specialist`, `ui-developer` at n=1) is a Demote candidate. The walker distinguishes them.

Verdict tiers

| Verdict | Meaning | Action posture | |---|---|---| | **Active** | Agent dispatch above floor, OR skill invoked-by-command / command invokes-a-live-skill, OR ≥2 non-boilerplate refs | Keep | | **Investigate** | Coverage < window (low-confidence), OR conflicting signals — **default-safe bucket** | Manual review | | **Demote** | Single dispatch (n=1), OR a skill with a single cross-ref and no command linkage | Consider downgrading docs/tier | | **Retire** | `dispatch===0` AND `nonBoilerplateRefs===0` AND `coverage>=window` | Strong remove candidate (verify first) |

Phases

Phase 1 — Resolve config + window

• Read Session Config for any `sunset-review.window-days` override; default to 90 (`DEFAULT_WINDOW_DAYS`).
• The window is the period over which dispatch counts are tallied. Keep the default unless the operator has a reason to narrow it.

Phase 2 — Run the walker (JSON mode)

Run the read-only walker and capture its JSON:

node scripts/lib/sunset/walker.mjs --json --window-days 90 > /tmp/sunset-walk.json

Exit 0 = walk completed (cold findings are exit 0, **not** an error). Exit 1 = bad args / surface dir missing. Exit 2 = system error. The walker writes no files — it is pure analysis.

Optionally scope to one kind for focused review:

node scripts/lib/sunset/walker.mjs --json --kind agent

Phase 3 — Classify & present (NEVER auto-delete)

• Group the `items[]` array by `verdict`, ordered Retire → Demote → Investigate → Active.
• Lead with `meta.lowConfidence`. If true, state plainly: "telemetry covers only N days (< window); all Retire candidates were downgraded to Investigate — do not retire anything this run."
• For each Retire/Demote candidate, show its `reasons[]` and `signals{}` so the operator can sanity-check the verdict against their own knowledge (a low-traffic-but-load-bearing item should