Handoff vs PatternBook

Handoff is an open-source tool for design system documentation and automation for teams and AI agents. A browser UI, REST API, and MCP server all read from the same underlying data. Figma is the only source currently wired up: a workspace can pull design tokens from Figma and push tokens, components, documentation, and assets to a registry. Handoff can create documentation pages for React and other component libraries, including live previews, properties, and tokens. Its token pipeline converts Figma tokens into CSS, SCSS, Tailwind, and DTCG outputs. Compatible agents such as Claude, Cursor, and Windsurf can access design system data through the MCP server; agents can also create component pages and usage guidelines for team approval. A promptable design space supports exploration with approved components, tokens, and brand patterns. Workspaces can use local filesystem-backed mode or a Postgres-backed registry, deployable with Docker or Vercel. The docs describe 56 MCP tools across 12 categories and an OpenAPI 3.1 specification for each registry’s REST API. Each registry currently serves one workspace, and the handoff-app package requires Node 20.9 or later. Other data sources and destinations are future direction, not shipped connectors.

PatternBook has no write-up on Specifiction yet; its figures are above.