# claude-code-plugin-gvt-construct3
The **`gvt-construct3` plugin** for Claude Code — Construct 3 platform knowledge, C3 agents, and a convention audit for any repository with a Construct 3 project on disk.
It bundles the **construct3-chef** and **c3-domain-manager** MCP servers, ships the `c3-explorer` and `c3-implementer` agents, and owns the canonical **C3 platform reference** (`plugin/docs/c3/`). It is **independent of the `gvt-dev` plugin** — installable on its own.
It is distributed through the [`claude-code-gvt-marketplace`](https://github.com/GenvidTechnologies/claude-code-gvt-marketplace) catalog (marketplace name `gvt-plugins`).
## Install
```text
/plugin marketplace add https://github.com/GenvidTechnologies/claude-code-gvt-marketplace.git
/plugin install gvt-construct3@gvt-plugins
```
The plugin declares `construct3-chef` and `c3-domain-manager` in its `plugin.json` (`mcpServers`), so they start when the plugin is enabled. They may appear as **"Pending approval"** — approve them once.
Then verify the repo satisfies the contract:
```text
/gvt-construct3:audit-c3-conventions
```
The audit checks for a **C3-project marker** and that both MCP servers are reachable at their minimum versions.
## What the plugin provides
**Agents** (dispatched via `subagent_type: "gvt-construct3:<name>"`):
| Agent | Model | Purpose |
|-------|-------|---------|
| `c3-explorer` | haiku | Read-only C3 recon — DSL, layouts, domain index, search |
| `c3-implementer` | opus | C3 mutations via recipes, layout/sprite scaffolding, project sync |
**Skill** (invoked as `/gvt-construct3:<name>`):
| Skill | Purpose |
|-------|---------|
| `audit-c3-conventions` | Read-only validator — C3-project marker + MCP server reachability/versions |
| `author-navigation-patterns` | Authors/validates a chef `navigation.targetPatterns` convention for wrapper-routed navigation |
| `build-reference` | Builds chef's `c3-reference` cache (built-in ACEs + concept docs) so `search-docs` resolves built-ins |
| `create-c3-op` | Authors + dry-run-validates a construct3-chef user-defined op wrapper (params + `{{PARAM}}` placement) |
**Bundled docs** (`plugin/docs/c3/`): the canonical **C3 platform reference** — event-sheet architecture, layouts, scripting, TS integration, and `construct3-guide.md`. The agents link these via `${CLAUDE_PLUGIN_ROOT}/docs/c3/*`.
**Bundled MCP servers** (`plugin.json` `mcpServers`): `construct3-chef` (recipes, DSL, scaffolding; its own docs at the `construct3-chef` server's `docs:///index` resource) and `c3-domain-manager` (domain index, overrides).
## The convention contract
`gvt-construct3` requires a consuming repo to be a Construct 3 project with the two MCP servers available. The full contract — including the optional, project-owned context the agents read from your `CLAUDE.md` — is documented in [`plugin/CONVENTIONS.md`](https://github.com/genvidtechnologies/claude-code-plugin-gvt-construct3/blob/HEAD/plugin/CONVENTIONS.md).
## Knowledge boundaries
- **C3 platform reference** (how Construct 3 behaves) → this plugin (`plugin/docs/c3/`).
- **Tooling reference** (recipe format, generators, CLI, recipe gotchas) → the `construct3-chef` server's `docs:///index` resource, versioned with the tool.
- **Project-specific facts** (named layouts, file paths, commit format, project gotchas) → the consuming repo.
## Contributing
The shipped plugin lives in the **`plugin/`** subfolder; the repo root is the dev workspace (a `gvt-dev` consumer). See [`CLAUDE.md`](https://github.com/genvidtechnologies/claude-code-plugin-gvt-construct3/blob/HEAD/CLAUDE.md) for the full layout.
- Skills are directories with `SKILL.md`; agents are flat `.md` files in `plugin/agents/`.
- Top-level frontmatter is fixed (`name`, `description`, plus Anthropic-supported fields); custom expectations go under `metadata.expects`.
- Run everything with `node scripts/ci/gate.mjs && claude plugin validate plugin`, from the repo root — that is exactly what `commands.validate` and CI both run.
- Test the audit alone with `cd plugin && node --test skills/audit-c3-conventions/scripts/test/*.test.mjs`.
