@celilo/mcp-dev-server

An MCP server that helps a developer adapt an application into a celilo module — the authoring companion to @celilo/mcp-server (which drives e2e runs).

Its job is to deliver celilo's authoring knowledge — capability contracts, the hook lifecycle, the manifest schema, the primitives guide — into the developer's own repo, where the celilo monorepo isn't checked out, and to offer a tight authoring loop (validate a manifest, scaffold a capability-wired module).

A minimal Model Context Protocol server over stdio (newline-delimited JSON-RPC 2.0), hand-rolled like @celilo/mcp-server — no SDK dependency.

Design: apps/celilo/designs/DEVELOPER_MCP_SERVER.md. The consumer-tool framing it builds on: openspec/changes/cele2e-consumer-tool/proposal.md.

Run it

bun run packages/mcp-dev-server/src/index.ts   # or: packages/mcp-dev-server/bin/celilo-dev-mcp

Register with an MCP client (.mcp.json / Claude config):

{
  "mcpServers": {
    "celilo-dev": {
      "command": "bun",
      "args": ["run", "/abs/path/to/packages/mcp-dev-server/src/index.ts"]
    }
  }
}

Tools

| tool | what it does | |------|--------------| | list_capabilities | Every capability a module can provide/require — version, one-line, provider module(s). | | describe_capability({name}) | The RAW TypeScript contract for one capability (source-of-truth data + methods), plus version + providers. | | list_hooks | Every lifecycle hook, its purpose, and whether it has required inputs/outputs. | | describe_hook({name}) | One hook's full inputs/outputs contract. | | validate_manifest({path}) | Runs celilo module check on a module dir; structured pass/fail. | | scaffold_module({id, requires?, provides?, zone?, …}) | Generates a capability-wired module skeleton: manifest.yml + hooks in the testable injectable-deps shape, a unit test per hook, and a cele2e e2e stub in tests/. Passes validate_manifest + bun test out of the box. |

Resources

| uri | content | |-----|---------| | guide://primitives, guide://module-development, guide://subsystems, guide://core-modules, guide://glossary | The authoring docs. | | schema://manifest | JSON Schema for manifest.yml. | | capability://<name> | One per capability — its raw .ts contract. | | hooks://contract | The full hook lifecycle contract. |

A resource whose source can't be resolved in the current environment is omitted from resources/list rather than erroring.

How it resolves things

• Capability names/versions + raw .ts contracts come from the installed @celilo/capabilities (it ships its src/).
• validate_manifest shells the installed celilo CLI (@celilo/cli). Override the binary with CELILO_BIN.
• Docs / manifest schema are read from @celilo/cli if installed, else from a monorepo checkout (CELILO_REPO_ROOT overrides the repo-root search).
• The hook contract is a small bundled copy of V1_HOOKS — it isn't exported from any published package today (see src/hook-contract.ts).

Status

v1 covers authoring — including generated hook unit tests (pure bun test, no harness needed). The full "test the module" half — driving a real deploy through @celilo/e2e — is deferred until that consumer surface stabilizes; the scaffold emits a skipped cele2e stub as the placeholder. See the design doc.

Dev tool, private, workspace-only for now.

Test

cd packages/mcp-dev-server && bun test