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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Code & DevOps

Open Components

Guidelines for UI components with a perfect UX, DX and AX, whether humans or AI agents write them.

Checks passed
14 / 22

1 failed · 7 not measured

Median response
80 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
6

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
312

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 86 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name open-components.

  • Pass
    Lists tools

    tools/list returned 6 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 80 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 85 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    19 of 20 parameters have a description (95%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Fail
    Website matches publisher

    The website host does not match the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-10-10T18:55:47.173409Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using Open Components

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http open-components https://mcp.opencomponents.dev/mcp

Capabilities

Tools 6

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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered
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.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected86 ms6
Connected74 ms6