JSON output

Every command accepts --json (before its own arguments). The full contract, with the shape of every command’s output and every error code, is docs/json.md in the repository; a test checks every command’s output against it.

Conventions

• Non-streaming commands print exactly one JSON document on stdout, with "ok": true on success.
• cheers, cruise, pipe and board -- CMD print newline-delimited frames instead: {"type":"stdout","data":...}, {"type":"stderr","data":...} and {"type":"event","event":...} as they happen, then exactly one {"type":"result",...}. Output that is not valid UTF-8 travels as "base64" instead of "data".
• A failure is {"ok": false, "error": {"code": "...", "message": "..."}} (with "type": "result" for a streaming command), and the process exits 125. The code is stable; the message is for people.
• boatparty’s own messages stay on stderr, prefixed boatparty: .
• No document carries a secret, with one deliberate exception: expose returns its URL, which may carry an access token.