feat: add mcp package

[joshblack]

Pitch: https://github.com/github/primer/issues/5363

Add an experimental @primer/mcp package that could be used in any context where MCPs are supported. This package runs a server that exposes the following tools:

• get_components: used to discover what components are available from Primer
• get_component: used to get the documentation for a specific component
• get_component_examples: used to get the examples for a specific component (specifically storybook examples around usage)
• get_patterns: used to discover pattern guidance that is available from Primer
• get_pattern: used to get the docs for a specific pattern

Below is a quick demo showing an idea of someone might interact with it in agent mode (or could be used by the Copilot agent directly)

Screen.Recording.2025-06-19.at.2.58.18.PM.mov

In the future, it would be awesome to include support for:

• init: setup a project that uses Primer
• suggest_design_token: suggest what design token to use for a specific usage
• General migration feedback, including tables and tools (like eslint autofixers) to use to help move to new

Finally, it would be great to have a demo showing how this will help an agent get more context in order to use Primer more effectively.

Changelog

New

• Add @primer/mcp package

Changed

Removed

Rollout strategy

• None; if selected, include a brief description as to why

This is an internal package for now

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Latest commit: 697c270

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size-limit report 📦

Path	Size
packages/react/dist/browser.esm.js	92.67 KB (0%)
packages/react/dist/browser.umd.js	92.54 KB (0%)