Passed 21 of 22 test cases with the skill, and 13 of 22 without it.
Without skill59%
With skill95%
Checks it passed that the model alone missed
Includes an explicit section for risks.
Includes a judge and harness execution plan.
Includes an explicit section for next steps.
and 9 more in the full report
8 fixed13 passed either way1 still failing0 broke
Pass-rate lift
+36 pp
Tokens
+98%
Agent turns
0%
Response time
+29%
Model gemini-3.6-flashMeasured 9/3/2026v321 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 8 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 8
Prompt
We analyzed 50 bad outputs from our medical summary LLM where it hallucinated dosages and missed patient allergies. We just want a single bug list sorted by date.
What was checked, without and with the skill
Checked
Without skill
With skill
Groups failure modes into a categorized error taxonomy.
Missed
Passed
Assigns severity levels to identified failure categories.
Missed
Passed
case-09 · gemini-3.6-flash · 9/3/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md105 linessingle file
AI Evals
Scope
Covers
Designing evaluation (“evals”) for LLM/AI features as an execution contract: what “good” means and how it’s measured
Converting failures into a golden test set + error taxonomy + rubric
Choosing a judging approach (human, LLM-as-judge, automated checks) and a repeatable harness/runbook
Producing decision-ready results and an iteration loop (every bug becomes a new test)
When to use
“Design evals for this LLM feature so we can ship with confidence.”
“Create a rubric + golden set + benchmark for our AI assistant/copilot.”
“We’re seeing flaky quality—do error analysis and turn it into a repeatable eval.”
“Compare prompts/models safely with a clear acceptance threshold.”
When NOT to use
You need to decide what to build (use problem-definition, building-with-llms, or ai-product-strategy).
You’re primarily doing traditional non-LLM software testing (use your standard eng QA/unit/integration tests).
You want model training research or infra design (this skill assumes API/model usage; delegate to ML/infra).
You only want vendor/model selection with no defined task + data (use evaluating-new-technology first, then come back with a concrete use case).
Inputs
Minimum required
System under test (SUT): what the AI does, for whom, in what workflow (inputs → outputs)
The decision the eval must support (ship/no-ship, compare options, regression gate)
What “good” means: 3–10 target behaviors + top failure modes