Debugging AI-Generated Regressions in Production

Incident triage starts with scope

Before root cause, define blast radius:

• affected endpoints or user flows
• first bad deploy window
• percentage of impacted requests

AI regressions are often subtle contract mismatches, not full crashes.

Build the minimal repro

Create the smallest failing case:

• one request payload
• one environment assumption
• one expected output

This prevents chasing multiple speculative hypotheses.

Diff-aware investigation

Compare:

• changed logic paths
• guard clauses removed by “cleanup”
• implicit defaults changed in refactor

AI often rewrites code “cleanly” but alters hidden assumptions.

Fast mitigation

Prefer reversible fixes:

• feature flag rollback
• route-level disable
• strict input fallback

Avoid broad hotfixes that increase uncertainty during incident response.

Postmortem rule update

Every regression should produce one policy update:

• new test requirement
• stricter prompting pattern
• explicit banned refactor type

This is how incidents translate into stronger AI coding standards.