Skip to content
THIRI logo
build.thiri.ai
Music theory for agents
Get a key
Docs Play Case studies Research Manual
Get a key Usage dashboard Builders community GitHub

Docs · Changelog

Changelog

Newest first. The engine is deterministic, so a grid change is the only thing that can alter a response you have already seen; those are marked Engine.

Updated 2026-10-02

2026-10-06

Billing

  • Paid plans on /keys: Theory Pro (10,000 calls a month, 120 a minute, 2 keys), Developer (100,000, 300, 10) and the MCP commercial licence (1,000,000, 1,000, 25). Checkout by card through Stripe; the account's keys change tier within a minute.
  • Free tier is now 1,000 calls a month at 60 a minute with 1 active key. Every tier is a hard cap. Keys from the earlier Builder tier carry the Developer limits.
  • Access-code redemption retired. T.H.I.R.I. Builders on Skool is the community and no longer changes a key's tier.

Unreleased

Site

  • On the branch, dated when it deploys: build.thiri.ai rebuilt as a developer site with quickstart, install, REST and MCP reference, keys and limits, errors, changelog.
  • Every instrument gets its own play space with goals and a "what the API returned" panel.
  • Case studies for Elk Audio and the score-to-picture work; the THIRI manual published in Markdown and PDF.
  • Get Started Guide (PDF) added; delivered on the keys page after sign-in.

2026-08-09

MCP

  • @bluesprincemedia/thiri-mcp 0.5.3 on npm. Current release; also ships thiri-conductor-mcp and thiri-composition-mcp binaries.

2026-08-01

MCP

  • thiri-mcp 0.5.2.

2026-07-29

MCP

  • thiri-mcp 0.5.1.

2026-07-23

MCP

  • thiri-mcp 0.5.0: conductor and composition servers join the package.

2026-07-16

Engine

  • Parser composes altered chords across all four families (dominant, major, minor, sus) with canonical alteration ordering. Minor keys accepted everywhere a key is.
  • Hosted remote MCP at mcp.thiri.ai redeployed with the same grid.

2026-06-19

MCP

  • thiri-mcp 0.3.0.

2026-06-16

MCP

  • thiri-mcp 0.2.1 to 0.2.3: packaging fixes.

2026-06-15

Integrations

  • n8n-nodes-thiri 0.1.0 on npm: all five endpoints as an n8n node and AI Agent tool.

2026-06-05

MCP

  • Hosted remote MCP server live at mcp.thiri.ai/mcp.

2026-06-01

MCP

  • thiri-mcp 0.2.0: first public release wrapping the v2 API.

2026-05-28

API

  • v2 endpoints live on chords.thiri.ai: analyze, resolve, voicing, reharmonize (eight techniques), conduct. Monthly quota headers on every response.
  • Launch tiers locked: free (1,000/month, 30 rpm) and Builder (50,000/month, 300 rpm).

Subscribe to the research feed for write-ups; releases are tagged on GitHub.

Next

Support →

Community, email, and what to put in a bug report.