[VDR][v0.6.0] TUT-63304da8 · Single-step tutorial's own unit test fails: output items now require a type discriminator #2695

Severity: 🟠 high | Category: Tutorials | Finding ID: TUT-63304da8

Location: fern/versions/latest/pages/environment-tutorials/single-step-environment.mdx:386

Problem

Section 5 tells you to paste three tests into tests/test_app.py. test_verify_without_tool_call builds an output item {"role": "assistant", "id": "", "content": [...]} with no type key. NeMoGymResponse gained a validator at nemo_gym/openai_utils.py:535 in commit 88d1692 (2026-08-10, after v0.5.0) that rejects it. Copy-pasting the tutorial's code verbatim gives 1 failed, 2 passed — the doc's success criterion for step 5 is unreachable.

Suggested fix

Add "type": "message" (and "status": "completed") to the assistant output item in the snippet, matching the shape used in fern/versions/latest/pages/agent-server/remote-agent.mdx:165. Consider a docs test that executes the tutorial's snippets in CI so openai_utils schema changes can't silently break them.

Evidence

ValidationError for NeMoGymResponse / output.0 / Value error, Responses API output items must include a type discriminator -> 1 failed, 2 passed

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