implement-plugin-parity

Implement Plugin Parity (EXECUTION)

This skill consumes an approved routing artifact written by analyze-plugin and executes its plan. It is the execution half of the parity subsystem; the planning half (analyze-plugin) and the drift check (plugin-parity-drift) are its siblings.

Hard approval gate (do this first)

1. Pre-flight validation gate. Run node scripts/plugin-routing-validate.mjs (optionally scoped with --routing-dir/--cache-root). If it exits non-zero → STOP; the artifact set is schema-invalid, version-stale, or trips an anti-pattern gate, and must be re-run through analyze-plugin and re-approved before implementation. Do not act on an artifact that fails this gate.
2. Read parity/plugin-routing/<plugin>@<marketplace>.json.
3. If the file is missing, malformed, or fails the routing-artifact schema (embedded below) → STOP with an error. Do nothing else.
4. If status is not exactly "approved" → STOP and print: "Artifact is <status>, not approved. A human must review the matrix and flip status to approved (visible in the git diff) before implement-plugin-parity will run." Make no changes.
5. Only when status === "approved" (and the pre-flight gate passed) do you perform the actions below.

This gate is the whole point of separating analyze from implement: nothing deterministic happens to the source tree until a human has approved the routing in the committed artifact. The gate is human/CI-enforced, not a programmatic interlock — "approval" is a committed, git-diff-visible status flag a reviewer flips, and this skill simply refuses to act unless it reads "approved". There is no separate lock; the audit trail is the git history of the artifact.

Routing artifact schema (the contract this skill validates)

The artifact this skill consumes is written by analyze-plugin; this is a compact copy of its schema so an executor reading this skill alone can validate it (the authoritative copy lives in analyze-plugin/SKILL.md and the design doc). Reject the artifact if any required field is missing or mistyped:

{
  "schemaVersion": 1,
  "plugin": "code-simplifier@claude-plugins-official", // canonical id == synced-from plugin-ref
  "pluginName": "code-simplifier",
  "marketplace": "claude-plugins-official",
  "upstreamVersion": "1.0.0",      // resolved from the cache; used for the synced-from stamp
  "analyzedAt": "2026-05-30",      // informational only
  "status": "proposed",            // "proposed" | "approved" — MUST be "approved" to run
  "components": [                  // inventory; each: { kind, id, path, classification, notes }
    { "kind": "agent", "id": "code-simplifier", "path": "agents/code-simplifier.md", "classification": "claude-agent", "notes": "" }
  ],
  "routing": {                     // exactly one entry per agent; outcome from the locked enum
    "codex":   { "outcome": "reimplement",              "actions": ["..."], "rationale": "..." },
    "cursor":  { "outcome": "claude-only",              "actions": [],      "rationale": "..." },
    "agy":     { "outcome": "reimplement",              "actions": ["..."], "rationale": "..." },
    "copilot": { "outcome": "enable-vendor-equivalent", "actions": ["..."], "rationale": "..." }
  }
}

Outcome enum (locked): already-native | re-point-mcp-lsp | enable-vendor-equivalent | claude-only | reimplement.

What it does (deterministic actions only)

For each agent's routing entry, perform only the declared actions, according to the outcome:

• already-native — no action; the existing fan-out already covers it.
• re-point-mcp-lsp — emit the MCP/LSP server into that agent's variant by invoking the existing generator/installer as a black box (see "Reused building blocks"). Do not hand-write variant manifests.
• enable-vendor-equivalent — enable the agent's native equivalent in its project-scoped marketplace per the declared action.
• claude-only — no action; documented as intentionally not ported.
• reimplement — scaffold a Lisa-native skill stamped synced-from: <name>@<marketplace>@<upstreamVersion> (the value from the artifact). v1 scaffolds only — create the skill shell + frontmatter pin; the actual reimplementation logic is out of scope per the issue. This is the only action that creates a drift-tracked artifact.

After any re-point-mcp-lsp work that flows through the build, run bun run build:plugins so the agent variants regenerate deterministically, and confirm bun run check:plugins still passes.

Reused building blocks (cite, never reimplement)

These are invoked as black boxes — this skill never edits them and never copies upstream plugin source into them:

• scripts/build-plugins.sh — build_plugin (Claude→Codex derive) and the per-agent fan-out (build_per_agent_variant). Triggered via bun run build:plugins.
• scripts/generate-codex-plugin-artifacts.mjs — Codex .codex-plugin/ derivation (skills + MCP pointer + hooks).
• scripts/generate-cursor-plugin-artifacts.mjs — Cursor variant (.mdc rules, mcp.json, native hooks).
• scripts/generate-agy-plugin-artifacts.mjs (generateAgyVariant) — agy variant; drops .mcp.json/mcpServers (MCP is user-global only).
• scripts/generate-copilot-plugin-artifacts.mjs — Copilot surfaces a bundled .mcp.json's servers as an inline mcpServers object on the manifest; also uniquely supports lspServers.
• src/agy/mcp-installer.ts — agy runtime MCP delivery (~/.gemini/config/mcp_config.json, serverUrl shape, _lisaManaged tagged-merge). The non-plugin path for agy MCP.

If a routed action needs a new emission path that none of these already provides (e.g. the first LSP routed to Copilot lspServers), do not silently attempt it — that is a separate work item. Surface it, leave it for a follow-up, and complete the rest.

Placement constraints

• Scaffolded reimplementation skills are Lisa-repo-internal and live at root .claude/skills/<name>/SKILL.md — NEVER in plugins/src/ or all/copy-overwrite/ (per PROJECT_RULES.md, same rule that keeps the parity skills root-only).
• Never port upstream plugin code. A reimplement scaffold is a Lisa-native shell carrying the synced-from pin so plugin-parity-drift can track it; the behavior is authored separately, not copied from the upstream plugin.

The synced-from stamp

Every scaffolded reimplement skill carries exactly:

synced-from: <name>@<marketplace>@<upstreamVersion>

where the three fields come from the approved artifact's pluginName, marketplace, and upstreamVersion. This stamp is what plugin-parity-drift reads to detect when upstream has advanced past the pinned version.

Definition of done

• The artifact was status:"approved" (otherwise this skill was a no-op error).
• Only the artifact's declared actions were performed.
• Any reimplement produced a root .claude/skills/<name>/SKILL.md stamped with the correct synced-from pin.
• No upstream plugin source was copied; no generator/installer file was edited.
• If the build was involved, bun run build:plugins is deterministic and bun run check:plugins passes.
• Any required new emission path was flagged as a follow-up rather than improvised.