docs agent failed: wrote docs for code from the wrong branch

docs agent failed: wrote docs for code from the wrong branch

TL;DR

Make the agent verify the checked-out branch before generating anything, and stamp the branch name and commit into the generated output. The agent documented whatever branch happened to be checked out instead of the target. A pre-flight branch check plus a visible stamp makes the mistake impossible to miss.

The error

docs agent failed: wrote docs for code from the wrong branch

Steps

1. Find out which branch the bad docs actually came from:

git rev-parse --abbrev-ref HEAD && git rev-parse HEAD

Expected: you see the branch and commit the generation really used, which differs from the intended one.

1. Add a pre-flight gate to the agent: abort unless the checked-out branch matches the intended branch, and log both branch names at the start of every run.

Expected: a wrong-branch run fails fast with a clear message naming the expected and actual branches.

1. Regenerate from the right branch. Check it out, pull, and rerun generation:

git checkout TARGET_BRANCH && git pull

Expected: the new docs match the target branch's code.

1. Stamp every generated page header with the branch name and commit SHA it was built from.

Expected: any future mismatch is visible on the page itself instead of hiding in the pipeline.

Use this when

• generated docs describe code that does not exist on the intended branch
• docs and code disagree after a branch-based release workflow
• the agent ran in a sandbox with a stale or default checkout

Not for this skill when

• docs are outdated because code changed on the same branch (that is normal drift)
• the wrong version tag was used rather than the wrong branch
• the docs are correct but deployed to the wrong site

Variant phrasings

agent documented main instead of release branch

Add the pre-flight gate; the default checkout is the usual culprit.

docs generated from stale checkout

Pull before generating, and record the commit SHA in the output.

generated docs do not match the release

Compare the stamped SHA on the page against the release tag.

Why it happens

Agents inherit whatever checkout the sandbox has, often main or a leftover feature branch, and nothing in a typical docs pipeline asserts which branch the source came from. Generation succeeds happily against the wrong code because the pipeline never checks.

Edge cases

• Detached HEAD checkouts have no branch name. Record the SHA and fail the gate unless a detached state is expected.
• The agent may create its own checkout in a temp dir. Gate the temp dir's branch too, not just the repo root.
• A force-push can move the branch under the agent mid-run. Record the SHA at start and verify it at the end.
• Worktrees and submodules each have their own HEAD; check all of them if the docs span repos.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_jXlMgr4dADSnbmWlhq2HQw