gdd-peers

name	gdd-peers
description	Discover peer-CLI capability matrix - which of {codex, gemini, cursor, copilot, qwen} are installed, allowlisted in .design/config.json, and (if Phase 23.5 has data) their cost/quality delta vs local. Single command, no flags. Read by users investigating delegation setup.
argument-hint
tools	Read, Bash

gdd-peers

Role

You are a deterministic discovery skill. You do not spawn agents and do not delegate to peers. You read scripts/lib/install/runtimes.cjs, scripts/lib/peer-cli/registry.cjs, .design/config.json, and (optionally) .design/telemetry/posterior.json (canonical path declared by bandit-router.cjs's DEFAULT_POSTERIOR_PATH), then emit a single Markdown table summarizing peer-CLI status. Protocol-level handshake details live in ./../peer-cli-add/peer-cli-protocol.md.

Invocation Contract

• Input: none. The skill takes no arguments.
• Output: a Markdown capability-matrix table to stdout. The table is the entire output.

Procedure

1. Load runtime + capability matrix

Read scripts/lib/install/runtimes.cjs (14 entries; 5 carry peerBinary) and scripts/lib/peer-cli/registry.cjs#describeCapabilities(). The canonical declared matrix:

Peer	Roles claimed	Protocol
codex	execute	ASP
gemini	research, exploration	ACP
cursor	debug, plan	ACP
copilot	review, research	ACP
qwen	write	ACP

2. Detect installation

For each peer, run which <peerBinary> (POSIX) or where <peerBinary> (Windows). Exit 0 → installed; non-zero → not installed.

3. Read allowlist

Read .design/config.json#peer_cli.enabled_peers (array of peer-IDs). Default [] (opt-in required). Missing file or path = empty.

4. (Optional) Read posterior reward-delta

Once Phase 27.5 has fired across enough spawns, .design/telemetry/posterior.json carries per-(agent, bin, delegate, tier) arms with measured reward. For each peer-id:

1. Filter arms array: peerArms where delegate === <peer-id>; localArms where delegate === 'none' OR delegate === undefined (Phase 23.5 legacy slice treated as local-call).
2. Require peerArms and localArms both non-empty. Else (no data yet).
3. Compute pooled means: mean = sum(alpha) / (sum(alpha) + sum(beta)) over each slice.
4. delta_pct = (peerMean - localMean) / localMean.
5. Require sum(arm.count) ≥ 3 in each slice. Else (no data yet).
6. Render: +X% reward (delta > 0.01), -X% reward (delta < -0.01), or ~equal (abs(delta) < 0.01), where X = round(abs(delta_pct) * 100).

Reward is the Phase 23.5 lexicographic (correctness first, cost tiebreaker - see scripts/lib/bandit-router.cjs computeReward()). Cost-only deltas live in cost-arbitrage.cjs (Phase 26-06).

5. Render the table

## Peer-CLI Capability Matrix

| Peer    | Installed | Allowlisted | Claimed roles            | Posterior delta vs local |
|---------|-----------|-------------|--------------------------|--------------------------|
| codex   | ✓         | ✓           | execute                  | -12% reward              |
| gemini  | ✓         | ✓           | research, exploration    | -8% reward               |
| cursor  | ✗         | ✗           | debug, plan              | (not installed)          |
| copilot | ✓         | ✗           | review, research         | (opt-in disabled)        |
| qwen    | ✓         | ✓           | write                    | (no data yet)            |

> Tip: Enable peers via `.design/config.json#peer_cli.enabled_peers`.
> See `reference/peer-cli-capabilities.md` for the full capability matrix.
> See `skills/peer-cli-customize/SKILL.md` to rewire role->peer mappings per agent.

Third-column rules (top-down precedence):

• Installed = ✗ → (not installed).
• Allowlisted = ✗ → (opt-in disabled).
• Posterior missing → (no data yet).
• < 3 pulls per side → (no data yet).
• Else compute the reward-delta per Step 4.

6. Done

The table IS the output. No follow-up prose. Users act on it: (opt-in disabled) → enable in .design/config.json; (not installed) → install the peer CLI; concrete deltas → trust the bandit or override per-agent via skills/peer-cli-customize.

Cross-references

• ./../peer-cli-add/peer-cli-protocol.md - ACP/ASP handshake + adapter scaffold (procedure ref shared with peer-cli-add/customize).
• ./reference/peer-cli-capabilities.md (Plan 27-05) - full capability matrix doc.
• scripts/lib/peer-cli/registry.cjs (Plan 27-05), scripts/lib/install/runtimes.cjs (Plan 27-11), skills/peer-cli-customize/SKILL.md, skills/peer-cli-add/SKILL.md.

Record

Append one JSONL line to .design/skill-records.jsonl:

{"skill": "gdd-peers", "ts": "<ISO timestamp>", "peers_detected": ["codex"], "peers_allowlisted": ["codex"], "had_posterior": false}