Coding agent stuck on 'did not conform to the edit format'

Every edit fails with 'SEARCH/REPLACE block failed to match' and the session can't continue.

Difficulty

Moderate

Time

~15 min

Steps

Fixed in

—

Last checked

2026-10-15

Unverified: we could not confirm from the sources that a fix shipped. Source: issue closed as completed, no linked fix. Last checked 2026-10-15.

Symptom

Every edit fails with 'SEARCH/REPLACE block failed to match' and the session can't continue.

Evidence what you'll see

SearchReplaceNoExactMatch error on the same file over and over
Often several blocks in one reply, where the first block changes lines the second one looks for

Cause

The model's SEARCH text doesn't exactly match the file, often because an earlier block in the same reply already changed those lines.

Fix steps

0 of 3 done

Step 1Read the troubleshooting page for edit errors.
Step 2Switch to the unified-diff edit format (a reporter used the udiff mode to get past it).
Step 3Ask for smaller, single-block edits, or add only the file being edited to the chat.

Your check marks stay in this browser only.

Verify the fix worked

The next edit applies cleanly and the file on disk changes.

Did this fix it?

Sources and credit

Summarized in our own words from these public reports. Credit goes to their authors.

Provided as is, without warranty. Test in a non-production environment and back up first. Security-related steps: verify against the official docs. Terms · Request removal or attribution change