check_accessibilityLABSCO SUMMARY
Two questions an accessibility check usually needs a person for.
axe-core catches the rule violations. The colour-blindness simulation catches what rules miss — a chart or a status badge that only works if you can tell red from green — and hands back an image you can actually look at.
What it is
An MCP server that drives Puppeteer and axe-core. One tool audits a URL for accessibility violations; the other re-renders the page through protanopia, deuteranopia and tritanopia colour matrices and saves the screenshots.
What you get
- Any URL audited against WCAG guidelines with axe-core
- Violations reported in detail, not merely counted
- Protanopia, deuteranopia and tritanopia simulated as saved screenshots
- A custom user agent, for pages that serve differently by client
- A waitForSelector, so the audit runs after the page has actually rendered
Requirements
Node.js v14 or higher and npm, with the server built by npm run build. The output directory must be given in the environment as an absolute path for the colour-blindness tool to save its screenshots; without it, output goes to ./output relative to the working directory.
Setup effort
Build from source
USE CASES
01
Auditing a page before it ships
Run axe-core against the URL and read the violations back in detail.
02
Checking a page that renders after load
Wait for the selector that marks the content ready, then audit.
03
Seeing whether a colour-coded UI still reads
Render the page through protanopia, deuteranopia and tritanopia and look at the screenshots.
04
Testing what a different client gets served
Set a custom user agent for the audit.
05
Making the case to the rest of the team
The simulation output is an image, which argues better than a violation count.
2 tools
Listed in project docs. Your client may show a different list.
simulate_colorblindBEFORE YOU INSTALL
What to know first
Tools you get
2 tools named in the project's documentation.
Requires
Node.js
Where it runs
The documented client runs the server on your machine.
INSTALLATION
Connect your client
MCP Clients
Cline
CLINE · JSON
{
"mcpServers": {
"web-a11y": {
"command": "node",
"args": [
"<YOUR_PATH_TO_MCP_WEB_A11Y>/build/index.js"
],
"disabled": false,
"autoApprove": [],
"env": {
"MCP_OUTPUT_DIR": "<YOUR_MCP_OUTPUT_DIR>"
}
}
}
}
