[MODEL] Unprompted branch opened by Claude Code

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• [x] I have searched existing issues for similar behavior reports
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Type of Behavior Issue

Claude modified files I didn't ask it to modify

What You Asked Claude to Do

This has happened twice.The second time I became worried. This branch was created about 45 minutes to an hour or so before I started work this morning. None of this was prompted by me. I was working on a separate branch to add features to my application which I gave Claude a prompt the night before, went to bed and Claude has made the appropriate changes to the codebase in my other branch. When I woke up, I accepted those changes and published them to my repo. When I went to the repo to merge those into my main branch, I noticed this new Claude branch that was created with six different commits over a period of time while I was asleep. Seems very suspicious to me.

The branch name (claude/nice-goodall-J1AF5)
The commit timestamps (May 11, 10:31–10:49 UTC)

What Claude Actually Did

Claude Code opened a new branch, modified some files for a problem that I was not asking it to solve.

Expected Behavior

It should not have done anything.

Files Affected

aws/images/wx-scripts/Dockerfile
s/script-local.sh

were the files that were attempted to be modified. Yes, auto-accept was on but for a totally different branch that I specifically opened.

Permission Mode

Accept Edits was ON (auto-accepting changes)

Can You Reproduce This?

Haven't tried to reproduce

Steps to Reproduce

_No response_

Claude Model

Sonnet

Relevant Conversation

Impact

Low - Minor inconvenience

Claude Code Version

2.1.138 (Claude Code)

Platform

Anthropic API

Additional Context

I think it must have been trying to build the product locally to make some changes, and ran into trouble. So, it decided to start making other changes to build. The changes seem suspect though. This is the second such event and both I believe were related to running the same script to populate data in a staging database.