[VDR][v0.6.0] TUT-dc0d74c9 · Tutorial's app.py replaces a scaffold it no longer resembles, breaking the scaffolded tests

[anwithk]

Severity: 🟠 high | Category: Tutorials | Finding ID: TUT-dc0d74c9

Location: fern/versions/latest/pages/environment-tutorials/single-step-environment.mdx:177

Problem

gym env init --resources-server X now generates an app.py built around ReverifyMode.STATELESS, an XVerifier mixin, a VERIFIER_FIXTURE = VerifierFixture(...) and tests/verifier_cases.jsonl, with tests/test_app.py doing from ..app import VERIFIER_FIXTURE. Section 3.2 says 'Open app.py and implement:' and shows a completely different file with none of that. Pasting it and running gym env test before Section 5 fails at collection. The tutorial never mentions VERIFIER_FIXTURE, verifier_cases.jsonl, or REVERIFY_MODE, so the reverify support the scaffold sets up is silently discarded.

Suggested fix

Re-sync Section 3.2 against the current scaffold: keep the MyWeatherToolVerifier + VERIFIER_FIXTURE structure and show only the deltas (tool route, get_weather, tool-usage verify, and updated verifier_cases.jsonl). Also update the generated-structure tree at line 61 to include init.py, tests/init.py and tests/verifier_cases.jsonl.

Evidence

tests/test_app.py:8: from ..app import VERIFIER_FIXTURE -> ImportError: cannot import name 'VERIFIER_FIXTURE' from 'my_weather_tool2.app'

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_{Found by the tutorial-walker critic in DX review Gym-1-20260821203248 — incremental from v0.5.0 to fa0d25158. Parent tracker #2214.}