`ac` lists Automatic plus the same open models as openrouter (●/$ marks), settings may pick one, and openrouter only shows with a key. in pro the hosted engine carries the workspace tools, 80 rounds, close_session and the person's MCP servers, shared with OpenServer through proLoop — tools run here, only messages go to the relay. a 402/429 from the relay shows its own sentence and re-reads the braincell meter. no preview, no lying: without a running preview write_piece says the file is on disk, ac_preview/ac_frame are not offered, and the prompt stops promising them. developer instructions no longer drop the piece contract. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>