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Setting Up for A11yNow MCP

Prerequisites​

  1. Node.js and npm must be installed on the machine.
  2. Access to the BarrierBreak npm registry: https://npm.barrierbreak.net.
  3. Registry credentials provided by BarrierBreak administrator.
  4. Chromium and Playwright for opening and scanning webpages.

Available Tools​

A11yNow MCP provides the following tools:

Scanning​

  • scan_page: Scans a single webpage for accessibility issues.
  • scan_site: Scans multiple pages across a website.
  • scan_urls: Checks a specific list of webpages.
  • scan_diff: Compares two scans to show issues that were fixed, which remains, and which are new.

Inspection​

  • check_contrast: Checks whether text and background colors provide sufficient contrast according to WCAG AA or AAA requirements.
  • page_outline: Shows the structure and headings of a webpage.

Fixing & Advice​

  • suggest_fix: Takes an accessibility issue and suggests the actual code or markup change needed to fix it.
  • ask_a11y_advice: Provides accessibility guidance and best practices.

Rules​

  • search_rules: Searches the accessibility rules used by the system.

Reporting​

  • export_sarif: Creates a SARIF report, which is standard format used by developer and security tools.
  • export_report: Creates a human-readable report.
  • wcag_conformance: Summarizes how well a website meets WCAG accessibility requirements.

Meta​

  • server_info: Provides information about the accessibility testing system itself.

Resources & Prompts​

  • Resource a11y://rules: Contains the complete collection of accessibility rules used by the system.
  • Prompt audit_component: Allows you to provide a specific UI component for an accessibility review.

Setting Up and Connecting A11yNow MCP​

Installation from the registry​

The server is published to BarrierBreak npm registry at https://npm.barrierbreak.net as a11ynowmcp. The A11yNow accessibility engines required by the server are already included in the package.

  1. Authenticate with the npm registry.
  2. Open a terminal and run. Run: npm login --registry https://npm.barrierbreak.net
  3. Enter the username and password provided by the administrator when prompted.

note

Authentication is required before installing A11yNow MCP.

  1. After successful authentication, install A11yNow MCP.
    Run: npm install -g a11ynowmcp --ignore-scripts --registry https://npm.barrierbreak.net

note

The --ignore-scripts avoids a failing native build of fsevents an optional, macOS-only Playwright dependency that the server does not require (without this option, the installation may fail with a node-gyp rebuild → binding.gyp not found).

  1. A11yNow uses Playwright and Chromium to open and scan webpages for accessibility issues.
    Run: npx playwright install chromium