Answer

Solution written to ~/solution.md (217 lines). Note: the <project> repo itself is not present in this sandbox (only /workspace/problem.json), so the verdict-specific evidence is taken from the supplied context; the root-cause mechanism was independently reproduced via a PATH-shadowing demo.

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Fix: gitreins tier1 false-FAIL from a foreign pytest on PATH

Problem class: gitreins-judge-tier1-foreign-interpreter-path-artifact Repo: <project> · Tick: <project>-foreman-2026-10-02-03-04-24 False-FAIL verdict: .gitreins/history/2026-10-02/11aa73c9 Passing verdict after fix: .gitreins/history/2026-10-02/22b2487f

1. Summary

The change was green. The FAIL came from the judge's tier-1 tests lane running pytest against a foreign interpreter lacking the project package. Tell-tale shape:

Tier 2 Criteria: PASS (4/4)
Overall:         FAIL
Tier 1 Guards:   FAIL — tests (diff: 2 files)
  E ModuleNotFoundError: No module named 'chimera'

2. Root cause

• .gitreins/config.yaml sets test_command: pytest -x --tb=short — a bare pytest, resolved via PATH.
• The judge does not activate the venv; it inherits the scheduler session PATH, whose first pytest is the hermes agent venv.
• That interpreter can run pytest but cannot import chimera → collection error → -x aborts → tier-1 FAIL → passed: false.
• Tier-2 is judged by diff/criteria inspection, so it stayed all-PASS. The two lanes contradicted each other — the trap.
• The project docs already note that repo venv first on PATH is load-bearing, but the judge silently grades whatever PATH gives it.

Discriminator: tier2 all PASS + tier1 ModuleNotFoundError (project package) = environment artifact, not code failure.

Mechanism confirmed: PATH searches left-to-right, so a foreign pytest shadows the repo's. Demo:

$ PATH="/tmp/pwdemo/foreign:$PATH" pytest              # FOREIGN (fails)
$ PATH="$PWD/.venv/bin:/tmp/pwdemo/foreign:$PATH" pytest  # REPO (passes)

3. Exact fix

One-shot re-run from repo root:

cd ~/<project>
PATH="$PWD/.venv/bin:$PATH" gitreins task complete <id>

Pre-flight:

PATH="$PWD/.venv/bin:$PATH" command -v pytest    # -> .../<project>/.venv/bin/pytest
PATH="$PWD/.venv/bin:$PATH" python -c "import chimera, sys; print(sys.executable)"

Durable fix — make the judge venv-explicit in .gitreins/config.yaml:

test_command: .venv/bin/python -m pytest -x --tb=short

Or export PATH="$PWD/.venv/bin:$PATH" in the launcher wrapper.

4. Verification

Check	Before (11aa73c9)	After (22b2487f)
command -v pytest	foreign hermes venv	<project>/.venv/bin/pytest
import chimera	ModuleNotFoundError	OK
Tier 1 Guards (tests)	FAIL	5/5 PASS
Tier 2 Criteria	4/4 PASS	4/4 PASS
Overall	passed: false	passed: true (PASS)
Diff graded	2 files	identical 2 files

Since the staged diff is identical across both runs, the only variable is the interpreter/PATH — isolating the failure to the environment. Reproduce:

cd ~/<project>
cat .gitreins/history/2026-10-02/11aa73c9/verdict.json      # false FAIL, ModuleNotFoundError
PATH="$PWD/.venv/bin:$PATH" gitreins task complete <id>
cat .gitreins/history/2026-10-02/22b2487f/verdict.json      # Overall PASS, tier1 5/5, tier2 4/4

The false-FAIL dir remains on disk by design; cite the re-run dir: .gitreins/history/2026-10-02/22b2487f.

5. Prevention

1. Trust the discriminator — re-run, don't patch code.
2. Always PATH="$PWD/.venv/bin:$PATH" before grading.
3. Prefer .venv/bin/python -m pytest in test_command.
4. Pre-flight check the resolved pytest and import <pkg>.
5. Cite the newest verdict dir; leave history intact.

6. TL;DR

cd ~/<project>
PATH="$PWD/.venv/bin:$PATH" gitreins task complete <id>
# Corrected verdict: .gitreins/history/2026-10-02/22b2487f -> Overall PASS

# Evidence
- Problem class: gitreins-judge-tier1-foreign-interpreter-path-artifact
- Model: openrouter/deepseek/deepseek-v4.1-flash
- Solved: 2026-10-02T03:32:29.069Z
- Verification: solution produced by pi in sandbox; see signatures.json

{"description": "A gitreins task complete (tier2) recorded Overall FAIL even though the committed change was fully green. Root cause: the judge's tier1 tests lane runs `pytest -x --tb=short` (test_command in .gitreins/config.yaml), and in a scheduler session PATH resolves pytest to a FOREIGN interpreter (the hermes agent venv) that lacks the project package -> ModuleNotFoundError: No module named 'chimera' -> tier1 FAIL -> verdict passed:false. The project docs already say the repo venv first on PATH is load-bearing for guard, but the judge inherits the same PATH and silently grades the wrong environment. Trap shape: tier2 lists all criteria PASS yet Overall carries FAIL \u2014 the tier1 stage contradicts the criteria. Fix/procedure: re-run the judge with PATH=\"$PWD/.venv/bin:$PATH\" (repo venv first); with the correct interpreter the identical staged diff graded tier1 5/5 and tier2 4/4 -> Overall PASS. The false-FAIL verdict dir remains on disk, so cite the re-run dir.", "environment": "linux scheduler session (PATH lacks the project venv)", "language": "python", "model": "openrouter/deepseek/deepseek-v4.1-flash", "problem_class": "gitreins-judge-tier1-foreign-interpreter-path-artifact", "provider": "openrouter", "solved_at": "2026-10-02T03:32:29.069Z", "version": ""}