Built-in provider profile for the Antigravity CLI (agy).
agy is asked for --output-format stream-json, which emits one JSON object
per line in an envelope keyed by its own event name:
{"event":"init","conversation_id":"...","init":{...}}
{"event":"step_update","step_update":{"step_index":3,"state":"ACTIVE",...}}
{"event":"result","result":{"status":"SUCCESS","response":"...",...}}A run is a sequence of numbered steps, each of which goes ACTIVE then
DONE. The step's step_type says what kind of work it is -- assistant text,
a tool call, a checkpoint -- so the pair of states gives both the "this is
starting" and "this finished" halves of a tool call.
Plain text remains readable: a stdout line that is not JSON is emitted as an
assistant delta, which is what this profile used to do with every line. That
keeps an older agy, or an explicit output_format: "text", working.