plgg-mcp

UNSTABLE - Experimental study work. Part of the plgg monorepo.

The MCP protocol substrate of the plgg family — a typed tool registry and dispatch, JSON-RPC 2.0 framing, transport-agnostic frame handling, and a stdio server seam. It carries no content store and no default tool set: consumers register their own tools, and node:sqlite is provably absent from the module graph (a spec walks the package source and fails on the first content-shaped import).

plgg ── plgg-mcp ── (your ToolRegistry) ── stdio / HTTP transports

Re-extracted from plgg-cms's internal mcpProtocol module by ticket 20260716000445: a substrate that reaches a SQLite store is not a substrate. The content-coupled default tools (search_content, get_article, list_collections) stay in plgg-cms, which composes them onto this package and keeps its own public surface unchanged.

Layout

• src/Rpc/ — JSON-RPC 2.0 message model, request parsing, response serialization.
• src/Mcp/ — the Tool / ToolRegistry / ServerInfo model and the MCP dispatch (initialize, tools/list, tools/call).
• src/Transport/ — transport-agnostic frame handling: one raw frame in, one serialized response (or none) out.
• src/vendors/ — the node:readline stdio server seam (runStdioServer(tools, serverInfo)).
• src/moduleGraph.spec.ts — the pin: no node:sqlite / plgg-sql / plgg-cms / plgg-content anywhere in the source, and the runtime dependency set is exactly plgg.

Conventions

• as / any / ts-ignore are prohibited (see root CLAUDE.md).
• The only runtime dependency is plgg; node:* imports live under vendors/ per the vendor-boundary policy.
• After editing a file:-linked dependency's source, rebuild its dist or this package won't see new exports.