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overlayrisk-witness

overlayrisk-witness

Local
overlayrisk.comDeveloper Tools0Updated 18w ago
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About overlayrisk-witness

overlayrisk-witness is a thin MCP client for running OverlayRisk's independent accessibility-overlay check on a public URL. It compares a page with an overlay enabled and disabled, then returns a documented finding and timestamp; findings are evidence, not legal compliance rulings.

Key features

  1. 01Before-and-after page capture
  2. 02Overlay detection
  3. 03Accessibility claim testing
  4. 04Timestamped finding
  5. 05Progress notifications

Use cases

  1. 01Reviewing a public site using accessiBe
  2. 02Checking a UserWay overlay's effect
  3. 03Documenting accessibility claim discrepancies

MCP support

The MCP server exposes the `witness_page` tool, which sends a public URL to OverlayRisk's hosted API and returns the free witness result. The full timestamped Risk Packet is available through the website's paid checkout.

Configuration

Local server config is the same for every client. Copy it into your client’s MCP config file.

mcp.json · Universal config
{
  "mcpServers": {
    "mertcanvural-overlayrisk-witness": {
      "command": "npx",
      "args": [
        "-y",
        "overlayrisk-witness-mcp"
      ],
      "env": {
        "OVERLAYRISK_API_URL": "<OVERLAYRISK_API_URL>"
      }
    }
  }
}
Run commandnpx -y overlayrisk-witness-mcp
Environment variables to set
OVERLAYRISK_API_URLOverride the hosted witness endpoint (defaults to https://overlayrisk.com/api/witness).

Local servers need a runtime on your machine (e.g. Node.js 18+). Config file locations differ by client; see your client’s docs.

Packages
npmoverlayrisk-witness-mcp0.1.0

Tools

1

Saved tool list · updated 3w ago

ParameterTypeRequiredDescription
urlstringYesHTTP or HTTPS public page URL to run through the free OverlayRiskWitness witness.

Details

From the project README

OverlayRiskWitness MCP server

A Model Context Protocol server that runs the free, independent before/after accessibility-overlay witness from OverlayRiskWitness on any public URL.

Accessibility overlay widgets (accessiBe, UserWay, and similar) are sold as one-line ADA/WCAG compliance fixes, but independent testing routinely shows the underlying page is unchanged for real assistive-technology users. This server lets an AI agent run the witness: it loads a page with the overlay on, then off, captures both states, and returns one documented finding where the page's public accessibility/compliance claims don't hold up — with a UTC timestamp.

Findings are evidence, not a legal compliance ruling. This server is independent of accessiBe and UserWay; it tests their effect, it does not sell or defend an overlay.

What this server is (and isn't)

This is a thin client. It contains no scanning logic and no secrets. Its single tool POSTs to the hosted API at https://overlayrisk.com/api/witness, which does the real work (overlay detection, headless before/after capture, claim extraction). The full timestamped Risk Packet is a paid checkout on the website — see overlayrisk.com/pricing. The MCP server is a free funnel; it never handles payment.

Tool

witness_page
Input{ "url": "https://example.com/checkout" } — a public HTTP/HTTPS page URL
SuccessThe free-witness JSON: runId, siteUrl, overlayVendor (accessibe/userway), pagesTested, claimsTested, didNotHoldUp, freeFinding, lockedFindingCount — plus a note linking to the paid Risk Packet
Error{ status, code, error } (e.g. overlay_no_effect, page_fetch_failed, witness_timeout)

A single witness run can take up to ~3 minutes on cold/heavy sites. That exceeds many MCP clients' default 60s request timeout. The server emits periodic progress notifications, so clients that honor resetTimeoutOnProgress stay connected automatically; clients that don't should raise their per-request timeout.

Install

Run directly with npx (no global install):

npx overlayrisk-witness-mcp

The process speaks MCP over stdio.

Claude Desktop / Cursor / other MCP clients

Add to your client's MCP config:

{
  "mcpServers": {
    "overlayrisk-witness": {
      "command": "npx",
      "args": ["-y", "overlayrisk-witness-mcp"]
    }
  }
}

Configuration

Env varDefaultPurpose
OVERLAYRISK_API_URLhttps://overlayrisk.com/api/witnessOverride the witness endpoint (e.g. for local dev)
OVERLAYRISK_TIMEOUT_MS200000Request timeout in ms

No API key is required — the free one-page witness is public.

Develop

npm install
npm run smoke   # offline handshake test (lists tools, no network)
npm start       # run the server on stdio

License

MIT © Mert Can Vural

Comments

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An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.