Public usernames only. The browser asks the site directly; nothing is signed in to.

Move phrases are a closed vocabulary and are read freely. Unique text — a finding, a card, a briefing — is a Speak button, and by default those buttons live only in Listen.

Stockfish runs in this browser by default; the 7 MB is fetched the first time you press Analyse. Point a remote engine here and the long jobs can run elsewhere — see docs/engine.md for the two transports and the reference server.

One block serving both the voice and the “Why?” explanations. Any OpenAI-compatible server works: OpenAI itself, a local LM Studio or Ollama, OpenRouter, your own proxy. The browser calls it directly, so the endpoint has to allow that (CORS) — the README has a four-line proxy for the ones that do not.

The key is stored in this browser’s localStorage, in plain text, and is sent only to the base URL above.

Off by default; the app is complete without it. A self-hosted server that stores five blobs — see docs/sync.md for the contract and the reference server.