storied sandbox takes an optional SCENARIO file whose contents submit as the player's first line, before the first key, the same as a typed line. Testing in the sandbox meant retyping the same opening prompt every session; now a canned file like scenarios/l3-cleric-and-zombies.md starts the scene by itself. The line goes through the normal submit path, so it shows on the prompt prefix in the transcript, records in the terminal history for recall with Up, and holds the prompt until the opening turn ends. An unreadable or empty scenario file fails before the terminal changes anything. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01HvctyUUkzw7PcNrjCGG6dF