"Understanding PRD and MVP concepts" matching MCP connectors:

Hosted x402 preflight for action authority, payment mandate, destination, expiry and replay.

Chords, scales, transposition, capo and tempo maths, with links to free interactive music tools.

Free restaurant profit check: 12 multiple-choice questions, a grade, and the biggest money leak.

Research extension listings and search results; track installs, keyword rankings, and competitors.