Summary
Coding agents look near-identical for the first few turns of a session; the meaningful divergence emerges around turn five, and it is how they treat the working tree. The question is whether each AI edit becomes its own commit or accumulates as an uncommitted diff. Fine-grained commits make every change an atomic, bisectable, individually revertible unit and protect correct early work from a late failure. Coarse, session-level rollback does not.
Key Points
- Aider commits after every edit the model lands, with a generated message. Each AI change is an atomic, bisectable unit: something broke →
git log→ revert that commit. Work from turn three is never lost to a turn-five spiral. - Cursor writes straight to the working tree, leaving staging to the user. In a long agent session the diff accumulates with no natural boundary between useful early changes and regrettable late ones, and the temptation to accept-all climbs along with the diff.
- Claude Code behaves like Cursor out of the box (writes, does not commit) but ships a hook system. A few lines of
PostToolUseconfig to stage and commit after every successful edit yields Aider's safety profile — most users never set it up. - Recovery granularity should match risk granularity. A whole-session revert (
git reset --hard+git checkout -- src/) means a failure in the last task discards correct work from earlier tasks in the same session. The recovery is coarser than the risk. - Per-task or per-edit commit granularity is the cheaper safety profile.
- Sub-agent parallelism (Claude Code
Tasktool) dispatches isolated workers in fresh context to research a module, draft an interface, or write migration tests in parallel, then rolls findings back — claimed to take a 20-file refactor from ~40 min to ~12. Cursor's interactive agent (Composer-1) and Aider are single-threaded by design.