The proactive status narration printed the internal 0-based step index, so the final step of a 13-step task announced "Starting Step 12" next to a card showing "12/13". Display now uses index + 1 in both the engine builders and the store-side updateStep narration; the 0-based tool/PROMPT.md contract is unchanged. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>