MCP Toolkit Editor

Author, validate, preview, and export MCP Description(mcpdesc) documents — entirely in your browser.

Pure client-side. No account, no backend. Your document never leaves your device.

Opens editor.mcptoolkit.org

The MCP Toolkit Editor showing a YAML MCP Description on the left and an interactive cards preview on the right.

Schema-driven editing

Monaco editor with JSON Schema autocomplete, inline squiggles, folding, and syntax highlighting for JSON and YAML.

Real-time validation

AJV validation against the MCP Description schema, plus semantic warnings for semver, empty capabilities, and duplicate names.

Interactive cards preview

Collapsible cards for server info, transports, security, tools, resources, and prompts. Click any type to jump to its source.

Markdown & export

Render Handlebars documentation, convert JSON ↔ YAML in one click, and export as .mcpdesc.json, .mcpdesc.yaml, or .md.

Generate a description from a live server

Point the mcpcontract CLI at any MCP server to produce anmcpdesc document you can open in the editor:

mcpcontract dump \
  --transport streamable-http \
  --url "https://your-mcp-server/mcp" \
  --output server.mcpdesc.json

Learn more about mcpcontract →

Your MCP Description stays in your browser.

No MCP server description content is uploaded to our servers. Edits persist locally via your browser's storage. Analytics only tracks anonymous product usage events.