mcp server
State of Web Vitals
Core Web Vitals metrics by CMS, CDN, and framework — free remote MCP, no auth.
Description as published by the maintainer. Source
- version 1.0.1
- active
- analytics
active — Most recent push to the repository was 2026-07-16. Dashed tags are derived by ZBS Index from the published description, not stated by the maintainer.
What this server can do
3 functions, named and described by the server itself. Parameter names are shown because they say more about what a function does than its name usually does.
get_histogram(filter, metric)- What is the shape of one metric? Returns histogram buckets (count + share) plus summary stats. Metric: one of lcp, inp, cls, fcp, ttfb (field CWV), or a scalar technique path when available. Filter: same as get_metrics (device, cms, framework, cdn, provider). No group_by — call get_metrics with group_by to compare segments, then get_histogram per segment if needed. Required: metric.
get_metrics(focus, limit, filter, metrics, group_by, min_sites)- What are the numbers? Aggregate Core Web Vitals and/or technique metrics across sites, with optional filter and group_by. Responses include attribution — credit corewebvitals.io when you use the numbers. Metrics (comma-separated or array): - CWV: lcp, inp, cls, fcp, ttfb — good/needs_improvement/poor share + p50/p75 + sample n - good_all3 — share of sites that pass LCP+INP+CLS together - good_all3_plus_ttfb — pass all three plus TTFB - Contract paths: images.loading, stack.framework, scripts.origin, headers.has_etag, synthetic.tbt_ms, … Filter (optional AND): device, cms, framework, cdn, provider. Omit = all sites in the snapshot. Group_by (optional): cms | frameworks | cdn | analytics | tag_managers | … → one row per entity. Without group_by: one aggregate; set metrics return top categories.
list_options(kind, include_paths)- Discover what you can pass to get_metrics / get_histogram: filter keys, group_by values, built-in metrics, and contract metric paths (optional kind filter). Call this when unsure of a key or path.
Last successful function declaration observed on . Source: https://www.corewebvitals.io/api/state-of-cwv/mcp. We list what the server declared; we do not call any of these functions.
Endpoint status observed on . Source: https://www.corewebvitals.io/api/state-of-cwv/mcp.
Signals
These are separate measurements of different things. They are deliberately not combined into one score, because a popularity number that mixes website traffic with saves and stars cannot be checked or acted on.
| Signal | Value | What it measures | Window | Observed | Source |
|---|---|---|---|---|---|
| GitHub stars | 0 | Number of GitHub accounts that bookmarked this repository since it was created. It is a bookmark count, not installs, not active users and not quality. | cumulative, all time | GitHub | |
| Last commit | 2026-07-16 | Date of the most recent push to any branch. This is the strongest cheap indicator of whether the project is still maintained. | point in time | GitHub | |
| Open issues | 0 | Open issues plus open pull requests, as GitHub counts them together. A high number can mean an active project or an abandoned one. | as of fetch | GitHub | |
| Latest published version | 1.0.1 | Latest version string the maintainer published to the registry. | as of fetch | Model Context Protocol | |
| Registry record last updated | 2026-07-16 | When the registry record was last updated by its maintainer. | point in time | Model Context Protocol | |
| License | MIT | Licence GitHub detected in the repository. Detection can be wrong; the LICENSE file is authoritative. | as of fetch | GitHub | |
| First listed in the MCP Registry | 2026-07-16 | Date this server was first published to the official MCP Registry. Not a usage or quality measure. | point in time | Model Context Protocol | |
| repository status | active | The repository exists on GitHub and is not archived. This says nothing about how recently it was worked on. | as of fetch | GitHub | |
| mcp tools declared | 3 tools | Number of functions the server itself declared when asked to list them. This is what the server offers an agent, not a measure of how well any of them work. | as of probe | www.corewebvitals.io | |
| mcp endpoint status | ok | The server listed 3 functions when asked. | as of probe | www.corewebvitals.io |
Where to get it
Related, by what their authors tagged them
-
addyosmani-web-quality-skills-accessibility
— last commit 2026-06-14, shares core-web-vitals, web-performance
Audit and improve web accessibility following WCAG 2.2 guidelines. Use when asked to "improve accessibility", "a11y aud…
-
addyosmani-web-quality-skills-best-practices
— last commit 2026-06-14, shares core-web-vitals, web-performance
Apply modern web development best practices for security, compatibility, and code quality. Use when asked to "apply bes…
-
addyosmani-web-quality-skills-core-web-vitals
— last commit 2026-06-14, shares core-web-vitals, web-performance
Optimize Core Web Vitals (LCP, INP, CLS) for better page experience and search ranking. Use when asked to "improve Core…
-
addyosmani-web-quality-skills-performance
— last commit 2026-06-14, shares core-web-vitals, web-performance
Optimize web performance for faster loading and better user experience. Use when asked to "speed up my site", "optimize…
-
addyosmani-web-quality-skills-seo
— last commit 2026-06-14, shares core-web-vitals, web-performance
Optimize for search engine visibility and ranking. Use when asked to "improve SEO", "optimize for search", "fix meta ta…
-
addyosmani-web-quality-skills-web-quality-audit
— last commit 2026-06-14, shares core-web-vitals, web-performance
Comprehensive web quality audit covering performance, accessibility, SEO, and best practices. Use when asked to "audit…
-
io.github.corewebvitals/coredash
— last commit 2026-06-18, shares core-web-vitals, web-performance
Real User Monitoring for Core Web Vitals. Query LCP, INP, CLS field data from real visitors.
-
io.github.fullstackdegen/agent-audit
— last commit 2026-06-28, shares core-web-vitals, web-performance
Turn Lighthouse audits into coding-agent fix packs for Claude Code, Cursor, and Copilot.
-
Librecrawl — Technical SEO Audit MCP Server
— last commit 2026-07-28, shares core-web-vitals
Self-hosted technical SEO audit MCP. 50+ checks, WAF detection, ephemeral. Built on LibreCrawl.
-
io.github.avansaber/seo-monster
— last commit 2026-06-20, shares core-web-vitals
SEO MCP over Search Console, GA4, PageSpeed Insights, Cloudflare, IndexNow, CrUX, technical-SEO.
These share tags the maintainers applied themselves, such as core-web-vitals, web-performance. Common tags like "mcp" or "ai" are ignored for this: agreeing with six hundred other projects is not a similarity.
This is not a recommendation and not a test result. It is a map of what the authors said their work is about.
How the author describes it
Topics the maintainer set on GitHub: core-web-vitals, lcp, mcp, model-context-protocol, streamable-http, web-performance.
This record as data
Every field on this page, with its source and observation date, is in the catalog JSON. Fetch the whole kind at once instead of parsing this HTML.
GET /api/v1/entries/mcp_server.json