any scale · any tuning · any guitar
custom (low→high):

⚡ AI coach

bring your own Anthropic key to switch it on
Your key is stored only in this browser (localStorage) and is sent straight to api.anthropic.com — never to us, never to a server. Your key, your browser, your bill.
Bring your own AI key

Paste an Anthropic API key to switch on the AI coach. It's stored only in this browser and goes directly to Anthropic — we never see it.

No key? Get one at console.anthropic.com. Typical cost: a fraction of a cent per question on Haiku.