
Open Components
Guidelines for UI components with a perfect UX, DX and AX, whether humans or AI agents write them.
What it can do
What data it sees
Do you need an account
No: the server works without sign-in
Guidelines for UI components with a perfect UX, DX and AX, whether humans or AI agents write them.
How to connect
How to connect Open Components to Claude
The server address to paste into Claude settings:
https://mcp.opencomponents.dev/mcp
- Open Claude (claude.ai or the desktop app).
- Go to Settings → Connectors.
- Click Add custom connector.
- Paste the server address copied below into Remote MCP server URL and click Add.
- In a chat, click + → Connectors and switch the new connector on.
Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.
Authorization
After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.
How to connect Open Components to ChatGPT
The server address to paste into ChatGPT settings:
https://mcp.opencomponents.dev/mcp
- Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
- Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
- Open Settings → Connectors and click Create.
- Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
- Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
- In a new chat open + → Apps/Connectors and enable the connector.
OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.
Authorization
On first use ChatGPT opens the service's sign-in window. Sign in and approve access.
How to connect Open Components to Cursor
The server address to paste into Cursor settings:
https://mcp.opencomponents.dev/mcp
Fastest: click Open in Cursor below and confirm the prompt.
Manually:
- In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
- Paste the JSON copied below into
~/.cursor/mcp.json(per project:.cursor/mcp.jsonin the repo root). - Save the file. The server appears in the MCP list; authorize it there if asked.
Authorization
If the service needs sign-in, an authorize button appears next to the server in the MCP list.
Server tool list (6)
Raw names from tools/list. Only developers need these.
| get-contract | Returns the contract of a component or a foundation, as YAML: its API (props, slots and events), its DOM contract (element, role, states, keyboard and parts), its tokens, and every rule in its checklist, each with a stable ID (like button/keep-focus), a level (must or should), a scope (component, usage or both) and how to check it. It holds every requirement in a fraction of the page's length, and it's the same file as https://opencomponents.dev/raw/docs/<path>.yaml. WHEN TO USE: first, before you build, review or explain a component or its tokens. WHEN NOT TO USE: for some of the rules only (by scope, layer, level or check), use list-rules. For the reasoning or the examples behind a rule, use get-page with its sections. |
| get-page | Reads a docs page as markdown, whole or just the sections you name. Component pages explain why each rule exists, with examples in React, Vue, Svelte, Angular, Solid, Astro and Vanilla: pass a framework to keep only its examples. WHEN TO USE: for the reasoning, an example or the details behind a rule (like the sections ["Loading"] of the button's page), or for a page without a contract, like the introduction or the roadmap. WHEN NOT TO USE: for the requirements alone, use get-contract or list-rules, which are much shorter. To find which page or section covers a topic, use search-docs. A page longer than about 8,000 tokens, like the button's, returns its outline instead: every heading with its anchor and length, so you can ask for the sections you need. So do sections that are too long to return together. |
| get-reference-implementation | Returns a shipped component's reference implementation: a Vue 3 component that meets every rule in its checklist, the tests that prove it, the helpers it shares with other components and its theme tokens. The live examples on the site run on this code. WHEN TO USE: to build a component that meets the standard, in Vue or by porting it and its tests to another framework, or to see how a rule is met in code. WHEN NOT TO USE: for the requirements, use get-contract. For how the component is used in another framework, use get-page with that framework. |
| list-components | Lists what the Open Components standard covers: the components that have shipped (like Button), the foundations every component follows (like Design Tokens), and the components planned on the Roadmap. WHEN TO USE: to check whether a component has a standard yet, to get the name the other tools take for it, or to see what's planned. WHEN NOT TO USE: if you already know the component, call get-contract directly. To find a topic in the docs, use search-docs. Shipped entries come with their page, their contract and how many rules they have. Planned ones have no page, contract or rules yet: hold them to the three layers and Design Tokens, following the Button's structure, as the build-component prompt does. |
| list-rules | Lists checklist rules as records, filtered by component, ID, scope, layer, level or check. Each rule has a stable ID to cite in reviews and commits, its level (must or should), its scope, its requirement, how to check it (like a unit test, a review or axe's button-name rule) and a link to it. WHEN TO USE: to review code rule by rule, to get only the rules that apply to a task, to look rules up by ID, or to find the ones a tool can check. Pass scope ["component", "both"] to build or review a component, and ["usage", "both"] to review a screen that uses it. WHEN NOT TO USE: for a component's API, DOM contract and tokens, use get-contract, which has every rule too. It returns up to 50 rules at a time, and total counts every rule that matches. When there are more, pass nextOffset as offset, with the same filters, to get the next page. A component meets the standard when it meets every must rule. Each should rule is expected unless there's a good reason not to follow it. |
| search-docs | Searches the whole standard, every section of every page and every checklist rule, and returns the best matches: where each one is, a short excerpt, and for rules, their ID, level and scope. WHEN TO USE: to find where a topic is covered when you don't know the page or the section, like "focus after delete", "spinner", "aria-pressed" or "dark mode". Then read a section with get-page, or rules with list-rules. WHEN NOT TO USE: to list a component's rules, use list-rules. To see which components there are, use list-components. Search for a few specific words rather than a whole question. |