Open-source PostMCP turns any OpenAPI spec into a token-optimized MCP server, cutting schema bloat up to 99%
Abraveram · reddit · 2026-09-23
A developer released PostMCP, an MIT-licensed open-source tool that addresses schema bloat when connecting APIs to Claude Desktop or Cursor via MCP — large OpenAPI specs can consume 40k–80k tokens of boilerplate before an agent makes a single call.
Features:
- Ingests OpenAPI 3.0/3.1/Swagger specs or URLs
- Token Diet engine compresses schema and payload output up to 99% via field masks and Markdown tables
- Built-in Visual Web Studio for live tool dispatch testing with Vercel AI Gateway
- 1-click config export for Claude Desktop, Cursor, and other coding agents
Available on npm (npm install -g @postmcp/cli) and GitHub, feedback welcome.
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