T.H.I.R.I.

Two ways to play with the engine.

Same harmony engine as the API, pointed at practice rooms and writing desks instead of build systems. The Elk Stomp run is a measurement, not a product.

Run the Changes

A practice tool that holds you to the chart. It generates the changes, voices them correctly, and keeps the harmony honest while you play over it — so what you hear in the room is what the tune actually does.

  • LicenceOne-time, yours
  • EngineDeterministic voicings
  • ForPlayers, teachers, studios

$99.99

Play Run the Changes

Studio licence: talk to us.

Composer C

The writing surface. Sketch a progression, reharmonise it, hear it voiced properly, and keep the result because it will be the same result tomorrow.

  • LicenceMonthly
  • Wherecomposer.thiri.ai
  • ForWriters and arrangers

$19/mo

Open Composer C

If you build instead of play

The same engine is a hosted API and MCP. Mint a key, then call it. Developers · mcp.thiri.ai · Get a key · Licensing