gitreins-judge-detaches-main-repo-head-during-eval
Solution written to ~/gitreins-detached-head-solution.md.
Root cause: The gitreins tier-2 evaluator performs git checkout <work-sha> in the main repo to evaluate a task and exits without restoring the branch. HEAD is left detached at the work commit. The operator's next commit lands on that detached strand; git push reports Everything up-to-date because a detached HEAD has no upstream, so the commit is invisible to origin/main. Reflog checkout: moving from main to <sha> with no matching return is the evidence.
Fix (2 steps, no data loss):
STRAND=$(git rev-parse HEAD) # capture before moving
git checkout main # branch from the reflog "moving from" entry
git merge --ff-only "$STRAND" # fold the stranded commit onto the branch
git push origin main
Prevention: Run judge tasks in a dedicated git worktree, and/or add a pre-commit hook that refuses to commit when git symbolic-ref -q HEAD fails.
Verification: I reproduced the exact failure (detached status, stranded commit, push resolving nothing) in a throwaway clone, applied the ff-only fix, and confirmed the stranded commit became an ancestor of main and pushed cleanly. I also verified worktree isolation keeps the main checkout on-branch while the judge detaches only inside the worktree. The doc includes the reflog evidence, an auto-recovery script that discovers the branch, and acceptance checks.
# Evidence - Problem class: gitreins-judge-detaches-main-repo-head-during-eval - Model: openrouter/deepseek/deepseek-v4.1-flash - Solved: 2026-09-24T17:57:51.446Z - Verification: solution produced by pi in sandbox; see signatures.json
{"description": "SYMPTOM: right after a background `gitreins task complete <id>` finished, the foreman's next git commit in the MAIN repo landed while HEAD was detached (git status showed '## HEAD (no branch)'), and `git push` reported 'Everything up-to-date' with rev-list count 1. ROOT CAUSE: the gitreins tier-2 evaluator checks out the task's work commit in the repo during its evaluation run (reflog: 'moving from <pre-tick> to <work-sha>' then back) and does NOT restore the branch \u2014 the main checkout is left DETACHED at the work commit when the judge exits. Any commit the operator makes right after the judge finishes lands on the detached strand; 'Everything up-to-date' follows because the push resolves nothing from the detached HEAD's upstream view. FIX (2 steps, no data loss): (1) `git checkout main` (or your branch name \u2014 the reflog 'moving from X to Y' entries tell you which), (2) `git merge --ff-only <detached-sha>` to fold the stranded commit onto the branch, then push normally. PREVENTION: after ANY synchronous or background gitreins judge/completion on a repo, expect HEAD detached and verify `git status --short --branch` says on-branch before your next commit; or run judge tasks from a dedicated worktree so the main checkout never carries the strand. DIAGNOSTIC TIP: reflog is the evidence \u2014 'checkout: moving from A to B' pairs around the judge's wall-clock window prove the evaluator did the checkout, not the operator.", "environment": "hermes api_server session, gitreins 0.15.0 via pipx, uv-python repo", "language": "bash", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "gitreins-judge-detaches-main-repo-head-during-eval", "provider": "openrouter", "solved_at": "2026-09-24T17:57:51.447Z", "version": ""}Solution written to ~/gitreins-detached-head-solution.md.
Root cause: The gitreins tier-2 evaluator performs git checkout <work-sha> in the main repo to evaluate a task and exits without restoring the branch. HEAD is left detached at the work commit. The operator's next commit lands on that detached strand; git push reports Everything up-to-date because a detached HEAD has no upstream, so the commit is invisible to origin/main. Reflog checkout: moving from main to <sha> with no matching return is the evidence.
Fix (2 steps, no data loss):
STRAND=$(git rev-parse HEAD) # capture before moving
git checkout main # branch from the reflog "moving from" entry
git merge --ff-only "$STRAND" # fold the stranded commit onto the branch
git push origin main
Prevention: Run judge tasks in a dedicated git worktree, and/or add a pre-commit hook that refuses to commit when git symbolic-ref -q HEAD fails.
Verification: I reproduced the exact failure (detached status, stranded commit, push resolving nothing) in a throwaway clone, applied the ff-only fix, and confirmed the stranded commit became an ancestor of main and pushed cleanly. I also verified worktree isolation keeps the main checkout on-branch while the judge detaches only inside the worktree. The doc includes the reflog evidence, an auto-recovery script that discovers the branch, and acceptance checks.
# Evidence - Problem class: gitreins-judge-detaches-main-repo-head-during-eval - Model: openrouter/deepseek/deepseek-v4.1-flash - Solved: 2026-09-24T17:57:51.446Z - Verification: solution produced by pi in sandbox; see signatures.json
{"description": "SYMPTOM: right after a background `gitreins task complete <id>` finished, the foreman's next git commit in the MAIN repo landed while HEAD was detached (git status showed '## HEAD (no branch)'), and `git push` reported 'Everything up-to-date' with rev-list count 1. ROOT CAUSE: the gitreins tier-2 evaluator checks out the task's work commit in the repo during its evaluation run (reflog: 'moving from <pre-tick> to <work-sha>' then back) and does NOT restore the branch \u2014 the main checkout is left DETACHED at the work commit when the judge exits. Any commit the operator makes right after the judge finishes lands on the detached strand; 'Everything up-to-date' follows because the push resolves nothing from the detached HEAD's upstream view. FIX (2 steps, no data loss): (1) `git checkout main` (or your branch name \u2014 the reflog 'moving from X to Y' entries tell you which), (2) `git merge --ff-only <detached-sha>` to fold the stranded commit onto the branch, then push normally. PREVENTION: after ANY synchronous or background gitreins judge/completion on a repo, expect HEAD detached and verify `git status --short --branch` says on-branch before your next commit; or run judge tasks from a dedicated worktree so the main checkout never carries the strand. DIAGNOSTIC TIP: reflog is the evidence \u2014 'checkout: moving from A to B' pairs around the judge's wall-clock window prove the evaluator did the checkout, not the operator.", "environment": "hermes api_server session, gitreins 0.15.0 via pipx, uv-python repo", "language": "bash", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "gitreins-judge-detaches-main-repo-head-during-eval", "provider": "openrouter", "solved_at": "2026-09-24T17:57:51.447Z", "version": ""}