DontAsk mode runs Claude Code with zero prompts. Any tool not on your allow list simply fails - no dialog, no escalation.

What it does

You pre-configure which tools and patterns are allowed. Claude either uses them or fails the turn. No human is in the loop. This is the headless-CI mode, designed for workflow runs, schedulers, and automated pipelines where waiting for a prompt would hang the job.

When to use it

GitHub Actions, GitLab CI, or cron-scheduled Claude Code runs.
Routines that run on infrastructure with no attached terminal.
Batch jobs where a hang is worse than a clean failure.
Automations that should fail loudly on unexpected tool needs.

Gotchas

Over-tight allow lists break the job for legitimate needs. Err on the side of explicit lists, not bypass.
Logs matter - you can't see the prompt, so make sure failures write enough detail to debug.
Combine with bare mode for deterministic runs when hooks and skills might interfere.

Official docs: https://code.claude.com/docs/en/permission-modes.md#allow-only-pre-approved-tools-with-dontask-mode