ascent-accessibility-mcp

ascent-accessibility-mcp

An MCP server that exposes the WCAG 2.2 success-criteria knowledge base used by Ascent Accessibility — the catalogue, manual-test guidance, remediation steps, human-reviewer profiles, localised Understanding content, and applicability logic.

It is pure and offline: no network calls, no browser, no credentials. All data is bundled from the MIT-licensed clean-room engine source in src/lib/standards.

Tools

Tool	Purpose
list_standards	Supported standards (WCAG 2.0/2.1/2.2 × A/AA/AAA) with tags and criteria counts
list_success_criteria	Criteria for a named standard, or filtered by version / level / principle
get_success_criterion	Full detail for one criterion (spec + Understanding URLs, nature, manual test, remediation, reviewer, affected communities)
search_success_criteria	Case-insensitive search over numbers, titles and slugs
get_remediation	Developer remediation guidance for one criterion
get_understanding	Localised Understanding content (zh-Hant / zh-Hans)
check_applicability	Whether a criterion applies to a page given its feature flags

Plus one resource catalogue (wcag://catalog), a per-criterion resource (wcag://sc/{num}, e.g. wcag://sc/1.1.1) and a review-page-against-wcag prompt.

Install

Claude Desktop / Cursor / VS Code (stdio)

{
  "mcpServers": {
    "ascent-accessibility": {
      "command": "npx",
      "args": ["-y", "ascent-accessibility-mcp"]
    }
  }
}

• Cursor: Settings → Features → MCP → + Add New MCP Server (or ~/.cursor/mcp.json).
• Claude Desktop: Settings → Developer → Edit Config (claude_desktop_config.json).
• Claude Code: claude mcp add ascent-accessibility npx -y ascent-accessibility-mcp.
• VS Code: Command Palette → MCP: Add Server.

Docker

docker build -f mcp/Dockerfile -t ascent-accessibility-mcp .
docker run -i --rm ascent-accessibility-mcp

Develop

cd mcp
npm install
npm run check   # tsc --noEmit
npm test        # vitest
npm run build   # esbuild bundle -> dist/server.js

npm run build bundles the catalogue from ../src/lib/standards into a self-contained dist/server.js; only @modelcontextprotocol/sdk and zod stay external.

License

MIT. The accessibility engine source it is built from is also MIT (humanity4ai/ascent-accessibility). WCAG content is © W3C, used under the W3C Document License.