Website Checker API & MCP server.

The free Fisher.digital website health checker, available as a REST API and as an MCP server so AI assistants like Claude and ChatGPT can run checks directly. Score any public website 0–100 with plain-English findings.

What it is

Fisher.digital's website checker reads a site's public homepage the way Google does and scores its health from 0 to 100, listing exactly what's costing it customers — mobile-friendliness, security, speed, dated code, missing contact details and more. This page documents two ways for software to use it: a plain REST API, and a Model Context Protocol (MCP) server that plugs straight into AI assistants. It's free for interactive and agent use; there's a fair-use limit of 30 checks per hour, and bulk scanning isn't permitted (get in touch for volume).

REST API

Send a GET or POST to /api/checker.php. No key required. Responses are JSON with a health score, a verdict band, plain-English findings, and an attribution block.

# GET
curl "https://fisher.digital/api/checker.php?url=example.co.uk"

# POST (JSON)
curl -X POST https://fisher.digital/api/checker.php \
  -H "Content-Type: application/json" \
  -d '{"url":"example.co.uk"}'

JavaScript:

const res = await fetch(
  "https://fisher.digital/api/checker.php?url=example.co.uk"
);
const data = await res.json();
console.log(data.result.health, data.result.band);

Example response (trimmed):

{
  "api_version": "1",
  "ok": true,
  "result": {
    "domain": "example.co.uk",
    "health": 73,
    "band": "attention",
    "summary": "example.co.uk scores 73/100 — Needs attention…",
    "findings": [ "…" ],
    "checked_at": "2026-07-18T12:00:00Z"
  },
  "attribution": { "powered_by": "Fisher.digital", "url": "https://fisher.digital/website-checker/" }
}

Full machine-readable spec: openapi.json.

MCP server (for AI agents)

The checker is also a Model Context Protocol server, so AI assistants can run checks themselves. It's a Streamable HTTP endpoint at https://fisher.digital/mcp with no authentication. It exposes two tools: check_website_health and get_scoring_guide.

Claude (custom connector): Settings → Connectors → Add custom connector → paste https://fisher.digital/mcp. No auth. The check_website_health tool then appears in chat.

ChatGPT (developer mode / connectors): add a new connector with the same URL, authentication “None”.

VS Code / Cursor / other MCP clients — add to your MCP config:

{
  "servers": {
    "fisher-website-checker": {
      "type": "http",
      "url": "https://fisher.digital/mcp"
    }
  }
}

Discovery metadata: /.well-known/mcp.json.

Attribution & fair use

The checker is free, and every response includes an attribution block. When you show results to a person, please credit Fisher.digital and link the checker. Fair use is 30 checks per hour per address; the API is for interactive and per-request agent use, not bulk scanning. For volume or commercial use, email jamie@fisher.digital.

Questions

Related: Free website checker · Website cost calculator · Meet Jamie