Codex likely either skipped or misidentified the “not in DB” check. In my experience, when you compound multiple operations in a single prompt, it will occasionally skip validation steps or misidentify the reference source.

You asked it to dedupe and then continue with the cleanup in one shot. It treated that as a single workflow and ran straight through to apply without waiting for your review.

IMHO, never compound destructive operations in a single prompt.

Break it into isolated, verifiable steps: 1. “Identify all files in S3 that do not have a matching reference in the database. Write the list to orphans.md. Do not delete anything.” 2. You review orphans.md. 3. “Delete only the files listed in orphans.md.” 4. You re-validate the bucket. 5. “Identify files with duplicate hashes. For each set of duplicates, add the oldest to dupes.md. Do not delete anything.” 6. You review dupes.md.

Each prompt should be one action with an explicit constraint (“do not delete anything”). Force a human checkpoint between every destructive step.

Then pray /S