Build a stdio MCP package

Prepared, unreleased authoring contract. This public page documents a reviewed future authoring workflow. Future authoring commands described here are not available in current releases; they do not claim that plugin-kit-ai@2 is available. Existing installer examples are identified separately. Public activation remains pending.

Choose stdio MCP when the package should supply a local process that communicates with the agent over standard input and output. The prepared template supports Node.js 22 or newer. This is a package scaffold; it does not establish that the host can start the server or that the tools behave correctly.

Create the scaffold

Use an existing disposable parent directory with no ./local-tools child. The runtime is an explicit template input.

Future installer-hosted authoring spelling:

agentplugins author init ./local-tools \
  --template mcp-stdio \
  --name local-tools \
  --description 'Provide local tools through a Node MCP server' \
  --runtime node

Equivalent future standalone authoring spelling; choose one:

plugin-kit-ai init ./local-tools \
  --template mcp-stdio \
  --name local-tools \
  --description 'Provide local tools through a Node MCP server' \
  --runtime node

Do not substitute a legacy Go, Python, shell, or TypeScript runtime flag. Those historical authoring lanes are described in v1 context, not implemented by this future template.

Review the runtime boundary

local-tools/
  plugin.json
  mcp.json
  package.json
  package-lock.json
  src/
    server.mjs
  README.md
  .gitignore

mcp.json records a stdio server with command node and argument ${PLUGIN_ROOT}/src/server.mjs. The package root token lets the consumer resolve the server file within the selected package; it is not your shell's current working directory.

The template includes the official MCP SDK dependency and its lockfile. src/server.mjs starts from a small hello tool. Review and adapt that source for your intended behavior, keeping application logs away from protocol output. No dependency install occurs during init, and no server process starts.

Gather static evidence

agentplugins author validate ./local-tools
agentplugins author inspect ./local-tools
agentplugins author test ./local-tools
agentplugins author compat ./local-tools --target codex,claude
agentplugins author doctor ./local-tools

Use plugin-kit-ai in place of agentplugins author for the equivalent future entrypoint. Static test inspects configuration, hygiene, Skills, and MCP; it is not an MCP handshake or a test invocation of hello.

Doctor inspects captured native files and executable metadata without processes or network. Its evidence is bounded. A toolchain finding cannot prove dependencies are installed, that imports resolve, or that the server starts successfully.

Prepare an honest README

Record Node.js 22 or newer as a runtime prerequisite and explain what tools the server provides. Identify the pinned dependency files and describe the remaining runtime verification work as separate work. Do not present bootstrap, dev, or runtime test commands as available v2 authoring operations.

A receiver needs both a conforming package and an explicit understanding of its execution requirements. Installation planning can evaluate target support, but it cannot stand in for independent runtime testing or user authorization to execute the server.

Continue with checks and evidence. Add instructions through extra Skills, or prepare the installer handoff.