Cleanor MCP

What cleanor-app/cleanor-mcp MCP server does

cleanor-app/cleanor-mcp MCP server exposes 22 read-only tools for image workflows and developer-focused calculations. Its image tools can fetch a public image URL, re-encode the image as WebP, AVIF, or JPEG, optionally resize it, and report before-and-after byte counts. It can also create SVG QR codes and dependency-free SVG placeholders.

Two tools provide Cleanor Labs research data. storage_capacity estimates how many photos or minutes of video fit within a storage tier after accounting for operating-system and filesystem overhead. image_format_savings compares WebP, AVIF, and JPEG XL with JPEG at matched perceptual quality and reports the HEIC conversion tax.

The remaining tools cover deterministic operations that benefit from exact execution rather than language-model estimation: hashes and HMACs, UUIDs, Base64, JSON validation and formatting, JWT decoding, regular-expression testing, cron descriptions, unit and base conversion, date and time conversion, URL parsing, text diffs, color conversion, palettes, slugification, and text counts.

How it works

The hosted service is available at https://mcp.cleanor.app/mcp using MCP Streamable HTTP. No API key, signup, or OAuth flow is required. MCP clients receive typed input and output schemas for the tools, and every tool is marked read-only.

optimize_image is the only tool that reaches outside the server: it downloads an image from a public URL, subject to a 25 MB input limit. The other tools are pure computations with no network access or persistent state. The server also exposes GET /v1/capabilities and POST /v1/optimize for non-MCP callers.

Setup and configuration

For a hosted connection, configure an MCP client with the endpoint URL and no credentials. Cursor can use the URL in its MCP configuration, and Claude Desktop supports it as a custom connector. The README also documents Claude Code and VS Code configurations.

A local stdio installation is available from npm:

npx -y @cleanor/mcp

The local package contains the same tool registry as the hosted service. Local image encoding uses the optional sharp dependency; the other tools do not require it. No environment variables or secret configuration are specified.

Tools and capabilities

The image group includes optimize_image, qr_code, and placeholder_image. QR generation accepts text or URLs and returns SVG output. Placeholders support dimensions, labels, and custom background and text colors.

The utility group supports exact cryptographic digests with SHA-1, SHA-256, SHA-384, and SHA-512, plus HMAC output in hexadecimal or Base64. UUID generation supports random v4 and time-sortable v7 identifiers. Other tools validate or transform common developer data, including JSON, JWT headers and payloads, Base64, URLs, regular expressions, cron expressions, colors, text, and numeric bases.

Use datetime for the current time or timestamp conversion in an IANA timezone, unit_convert for supported physical and data units, and diff for line-based text comparison. cleanor-app/cleanor-mcp MCP server also includes palette generation from a base color and exact counts for Unicode code points, UTF-16 units, words, lines, and UTF-8 bytes.

Limitations and notes

JWT decoding does not verify signatures and does not require or store a secret. MD5 is not available. Regular-expression results are capped at the first 100 matches, and diffs support up to 1,000 lines per side. Image optimization accepts only public URLs and limits input to 25 MB.

The hosted endpoint is unauthenticated, so developers should consider the data they send to its tools. cleanor-app/cleanor-mcp MCP server is licensed under MIT according to the repository badge and provides read-only operations rather than tools that modify external systems.