Give your AI coding agent eyes. RenderLens is an MCP server with 3 tools: render (code → screenshot), audit (Lighthouse + WCAG accessibility), diff (pixel-level visual comparison). Free during beta — 100 calls/month, no API key, no signup.
Overview
What is RenderLens?
An MCP server that gives your AI coding agent eyes. Instead of writing UI code blind, your agent can verify what it builds visually.
Tools
render
Send HTML or React code, get back a screenshot. Supports custom viewports, full-page capture, and framework auto-detection.
audit
Run Lighthouse + WCAG accessibility audits on any code. Returns violations, passes count, and scores.
diff
Compare two versions of UI code pixel-by-pixel. Returns a diff image and percentage of changed pixels.
Quick Setup
Works with Claude Code, Claude Desktop, Cursor, Windsurf, and any MCP client.
Features
- No API key, no signup — just paste the config and go
- 100 free calls/month during beta
- Playwright-powered rendering
- GDPR compliant (no code stored, IPs anonymized)
Server Config
{
"mcpServers": {
"renderlens": {
"type": "streamable-http",
"url": "https://app.renderlens.dev/mcp"
}
}
}