Headless (elph run)

Use the same harness without the TUI — scripts, CI, and editor glue that is not ACP.

elph run "write a test"
elph run --mode=plan "design the auth boundary"
elph run --output=json "summarize this diff"

Formats: plain, pretty, json, stream-json, stream-message-json.

Provider and model follow env / session defaults (ELPH_PROVIDER, ELPH_MODEL). Auth is the same as the TUI — see Providers.