Baseline Checker MCP Server

MCP server to check web feature compatibility with Baseline standards.

Baseline Tooling Hackathon - Accelerate availability of modern web features

Installation

npm install
npm run build

Related MCP server: Accessibility Testing MCP

MCP Configuration

VSCode

{
  "servers": {
    "baseline-checker": {
      "command": "node",
      "args": ["/<absolute path to your project>/dist/index.js"]
    }
  }
}

Cursor / Other editors

{
  "mcpServers": {
    "baseline-checker": {
      "command": "node",
      "args": ["/<absolute path to your project>/dist/index.js"]
    }
  }
}

Test with MCP Inspector

You can test this MCP server with the inspection tool:

npx @mcpjam/inspector@latest

More info: https://github.com/MCPJam/inspector

Available Tools

1. check_baseline

Analyzes complete HTML/CSS/JavaScript code for Baseline compatibility.

Input: Complete code to analyze Output: Detailed compatibility report with:

• Compatibility percentage

• Detected web features grouped by status (Baseline, Non-Baseline, Discouraged)

• Browser support warnings

• Specific recommendations and alternatives

Usage: "Analyze this code for Baseline compatibility: [paste your code]"

2. check_baseline_from_selection

Automatic code retrieval tool.

Input: Source type (selection, active_file, or clipboard) Output: Instructions for the AI agent to:

• Use editor tools to access the selected/active code

• Pass the retrieved code to the check_baseline tool

• Provides guidance for proper workflow integration

Purpose: Directs AI agents to use proper workflow for code analysis

Usage Examples

• "Analyze this code for Baseline compatibility: [your code]"

• "Check if this HTML/CSS/JS is Baseline compatible"

• Use check_baseline tool with your code for immediate analysis

Resources

• MCP Documentation

• Web Features