Follow a session live

A server-sent event stream of the run as it happens. Before the sandbox starts you get status events ({status}); then the harness's own events (message, tool_use, tool_result, thinking, result, error), each with an id. The stream ends with done, whose data is {status, output, result}: result is the SessionAnswer, or null when the run produced none. On a session that already finished the stream sends only status and done, never the history: read that from GET …/messages or GET …/trajectory. An error without a type ({code, message}, code one of NOT_FOUND or STREAM_ERROR) ends it early. An API key receives only these events. Reconnect with Last-Event-ID (or ?cursor=) to resume after the last event you saw. Comment lines (: keepalive) keep idle connections open.