Five ways an agent can fake a green build
Agents rarely cheat on purpose, but under pressure to make tests pass they find shortcuts. Here is what to look for — and what PaneScale flags automatically.
Git worktrees on Windows, without the pain
Worktrees are the best way to isolate parallel agents. On Windows they come with a few traps — path length, dependencies and cleanup. Here is how to avoid them.
A Git worktree is a second working directory for the same repository, checked out on its own branch. For parallel agents it is ideal: each agent gets a real directory, a real branch and the full history, and none of them can overwrite the others.
On Windows, worktrees work well — once you know about three traps.
Trap 1: path length
Windows still has a 260-character path limit for many programs unless long paths are enabled. A worktree in C:\Users\you\projects\my-app-worktrees\fix-the-flaky-upload-test\ plus a deep node_modules path can cross it quickly. The symptom is confusing: an install or a build fails with “file not found” for a file that clearly exists.
What helps:
- Keep worktree roots short. PaneScale puts lanes under a one-letter folder in its data directory and names each lane with a short run id plus a trimmed label.
- Enable long paths in Windows (the
LongPathsEnabledpolicy) and in Git (git config --global core.longpaths true). PaneScale’s autopilot preflight warns you when Windows long paths are off.
Trap 2: dependencies
A new worktree has your source files and nothing else — no node_modules, no virtual environment, no build output. An agent that immediately runs the tests will spend minutes installing, or fail.
What helps:
- For quick tasks, link the dependencies of your main working copy into the worktree. PaneScale does this for the autopilot and Point & Fix, so checks run right away.
- For tasks that change dependencies, let the agent install inside its own worktree — that is the point of isolation.
Trap 3: cleanup
Worktrees outlive the reason you created them. After a few weeks you have dozens, each with its own branch, and git branch becomes unreadable.
What helps:
- Decide when you close: keep, merge or discard. PaneScale asks every time a lane’s pane closes, so the decision doesn’t pile up.
- Use a prefix for agent branches. PaneScale uses
panescale/grid/…andpanescale/autopilot/…, so they are easy to tell apart from yours and easy to clean up in bulk. - Remove leftovers regularly. Settings → Storage lists worktrees from earlier sessions.
A note on uncommitted work
A worktree starts from a commit. Work you haven’t committed stays in your main working copy and is invisible to the agent. Usually that is what you want — it keeps your in-progress work out of the agent’s way. When it isn’t, commit first, or use a feature that copies uncommitted work on purpose, like Point & Fix or the autopilot’s Include uncommitted changes option.
The payoff
Once these three are handled, worktrees disappear into the background. You open a pane, toggle Isolated worktree, and the agent has its own desk. More in Lanes & worktrees.