Where does the bug appear (feature/product)?
Somewhere else…
Describe the Bug
Cursor Cloud has dodgy system prompt causing it to get confused about branch names. It wouldn’t push/create PRs because it was holding a cursor/… prefix for the branch locally and pushing to that, but showed the branch name without the cursor/ prefix in the sidebar.
It says this is because of some system prompt, which is definitely new because last week I had no such issues with the Cloud Agents.
[me]
> The branch exists on the remote. The PR creation tool has a bug where it strips the cursor/ prefix. Here's the direct link you can use to create the PR manually:
> What PR creation tool? Give me full information that you have on this tool
[agent]
The ManagePullRequest tool is one of the built-in tools I have access to. Here's what I know about it:
What it does: Creates or updates pull requests for the current repository.
Available actions:
create_pr — requires title and body, optional base_branch and draft (defaults to true)
update_pr — optional pr_url, title, body, base_branch
What happened: When I called create_pr, the tool internally resolves the head branch from the current git branch. My branch was cursor/smcgown/... but the error message said:
the head branch "smcgown/..." does not exist on the remote
It stripped the cursor/ prefix, looking for smcgown/... which didn't exist at that point. That's why I then pushed the same commits to a branch without the cursor/ prefix (git push origin cursor/...:smcgown/...) and the PR creation succeeded on the second attempt.
So it's not really a "bug" — the tool likely expects branch names without the cursor/ namespace prefix, or it auto-strips it assuming that's a local-only convention. The workaround was just pushing to a matching branch name that the tool could find.
[me]
> Why did your branch start with cursor/
[agent]
Because of a rule in my system instructions:
CRITICAL: the branch should start with 'cursor/' and end with matching session id, otherwise push will fail with 403 http code.
I'm told that branches must be prefixed with cursor/ or pushes will be rejected with a 403. So when I created the branch I named it cursor/smcgown/... to comply with that rule.
Turns out the push worked fine, but then the PR creation tool stripped the cursor/ prefix when looking for the head branch on the remote. The workaround was just pushing the same commits to a second branch name without the prefix.
Steps to Reproduce
Start a cloud agent
It won’t create a PR anymore
Ask it why and its because of the above repro
Expected Behavior
Creates a PR and doesn’t get confused about branches.
Operating System
MacOS
Version Information
Cursor Cloud latest version (refreshed today)
Does this stop you from using Cursor
Sometimes - I can sometimes use Cursor