Diagnostics

fut doctor performs a bounded, read-only diagnosis of the client environment:

fut doctor
fut --json doctor
fut --socket /path/to/fut.sock doctor

It does not start or stop a daemon, create or repair directories, remove stale sockets, open a project, spawn a terminal, enter raw mode, or change terminal state.

Checks

Doctor reports:

Protocol epoch 0 is a development epoch. A successful handshake does not promise compatibility between different development builds.

Nerd Fonts

Terminal processes have no reliable cross-terminal API for discovering the active font. Doctor therefore reports the active font as unknown and asks for visual verification. It does not infer support from the terminal program or claim that an installed font is selected.

Enabling preset = "nerd_font" makes the icon check a warning until visually verified; it does not prevent Fut from starting.

Exit status

Diagnosed errors are part of the complete report rather than a secondary command failure.

JSON

fut --json doctor writes one compact success-envelope-shaped report to stdout, even when the report’s status is error and the process exits 1:

{"version":1,"command":"doctor","result":{"status":"warning","checks":[{"id":"config","status":"ok","summary":"valid defaults; no configuration file"}]}}

Check statuses are ok, info, warning, and error. Details include structured paths, environment hints, protocol versions, icon glyphs, and the explicit active_font: "unknown" limitation where applicable.