Investigate omitted contract and design details in write-naturally #4

Problem

Some public rewrite outputs omit details required by their cases despite reading the core skill and technical-design reference.

From the public suite in PR #2:

• D2 drops parameterized SQL ownership and the explicit exclusion of database pool size as the correctness mechanism.
• D3 drops the selected EF Core/Npgsql technology and the claim's EF transaction.
• D7 explains the output limit but drops max_completion_tokens, the required field used to send that limit.
• C11 keeps the new workshop time, room and reply deadline but omits the old time. Confirm whether retaining that old time is necessary for this request before treating the omission as a skill defect.

The skill already says to preserve relevant guarantees and contract identifiers, and to remove incidental implementation details. These failures do not establish whether the cause is conflicting guidance, model adherence or an overly strict case expectation.

Proposed work

• Decide which details are required for the reader's decision or contract, and align the writer request and grader with that intent.
• Calibrate the cases before changing guidance; retain meaningful omissions as failures.
• Compare focused, repeated runs with and without the skill to investigate its effect.
• If evidence supports a skill change, make a small general clarification at the appropriate scope. Technical abstraction guidance belongs in the technical-design reference.

Acceptance

• Required architecture choices and contract fields survive the rewrite, while incidental wiring can still be removed.
• The scheduling case has an explicit, justified retention requirement.
• Any proposed guidance change improves repeated focused results without regressing the removal of implementation plumbing.
• Record remaining failures and grader disagreements rather than tuning criteria to the latest output.

Writer: gpt-6.1-sol; grader: gpt-5.6-luna; reasoning: medium. Reproduce using the fictional public cases; no captured private writing is needed.

Additional coverage lives in the private eval repository.