Harmon
A policy-driven music daemon — one control plane over Spotify, Apple Music, and YouTube Music, for humans and agents alike.
- Session policies — focus, workout, meditate — with hard constraints and soft weights
- `nudge` shifts the session's energy live without restating everything
- An honest capability matrix — providers aren't pretended equal
- ~35 MCP tools so your assistant can run the queue
Music control is fragmented across three providers’ apps. Harmon puts one daemon on loopback and lets a human at a CLI, a web player, a menubar, or an AI over MCP all speak the same language.
The heart is the session policy engine: declare focus with no vocals and a tempo ceiling, or energize with a target energy, and the queue refills itself to match. Mid-session, nudge bends the energy without renegotiating.
Where a provider can’t do something, Harmon fails explicitly instead of faking it. Secrets live in an AES-256-GCM envelope with Keychain first. The macOS menubar does the Liquid Glass notch-island thing, because craft is allowed to be fun.