Guides

Choose the harness and workflow before the model

Tool design, context assembly, permissions, and retries shape agent behavior.

3 min

A concise editorial guide, not a universal recommendation or guarantee.

Decision rule

Write down the job: repository editing, research, delegation, or unattended batches. Then test the harness permissions, diffs, recovery, and model-provider support. The same model can behave differently because harnesses build prompts and tool loops differently.

Practical checklist

  • Test recovery from a failed tool call.
  • Review permissions before unattended work.

Sources checked

These first-party or authoritative sources ground the note. Checked 2026-08-16.

  1. OpenAI Codex documentation(opens in a new tab)