LLM Evaluation Design: From task sets and scoring criteria to model regression gates

A common LLM-evaluation mistake is collecting many attractive examples first and then looking for a score to explain them. Good evaluation starts with the goal, failure cost, and judgment criteria.

The LLM Evaluation Design Skill builds representative datasets, rubrics, and decision thresholds, so a score has a known meaning and limitation.

This guide provides an actionable checking framework and examples, helping you make evidence-backed judgments even when uncertainty remains.

LLM Evaluation Design Skill: what it is for

LLM Evaluation Design is for work that needs a clear, handoff-ready testing judgment. It keeps project material, the basis for each decision, and the next action on the same trail—so a reader can see what to inspect before choosing how to execute and review it. This guide works through one concrete scenario and keeps human decision boundaries visible.

Start with the source Skill

The complete execution contract lives in LLM Evaluation Design prompt. The source directory also contains 3 evaluation cases for checking whether an output follows the contract.

The entry point calls out these constraints:

  • map metrics to real tasks
  • calibrate and audit LLM judges
  • separate offline quality from online business metrics

Begin with project facts

Put the material you have on the table. Gaps may remain; their status needs to stay explicit.

MaterialWhat to provideWhat to do when it is missing
Goal and scopeDesign task sets, rubrics, references, review flow, and regression gates for a support-summary modelName journeys outside this pass
Version and environmentRequirement version, build, environment, time windowStay in design or analysis mode
EvidenceRequirements, interfaces, logs, metrics, traces, or defectsSeparate facts, assumptions, and open questions
Decision boundaryRisk approver and actions that are not authorizedName the owner and next step

Use a request like this:

Use the llm-evaluation-design Skill.

Task: Design task sets, rubrics, references, review flow, and regression gates for a support-summary model
Inputs: [versions, links, log paths, or reports]
Scope: [included and excluded objects]
Constraints: [time, data, permissions, compliance]

Audit the inputs first. Order results by risk and evidence strength. Label unsupported claims as assumptions and give a validation method.

Make the result usable by the next person

Output fieldWhy it existsExample status
Finding or judgmentDescribes observed behavior, difference, or riskConfirmed / Assumption / Open
BasisPoints to a version, log, trace, test, or requirementsource_id or link
ImpactExplains affected users, journeys, or release decisionP0, P1, or accepted residual risk
Next actionNames verification work and an ownerOwner, date, expected evidence

Do not write “passed” without a run record, query result, or source artifact. Static analysis and runtime proof are different things.

Run one focused pass

Start with a bounded pass—Design task sets, rubrics, references, review flow, and regression gates for a support-summary model. Put the input version, time window, and accountable owner in one place. Then link each judgment to an artifact. Finish with one validation action that can change the decision.

The evaluation set must cover high-value tasks, risky samples, and failure boundaries with reviewable scoring. The handoff should include an evidence index, assumptions that still need checking, and an action the next person can run without reconstructing the conversation. Plain work. It holds up.

Run one focused pass

Start with a bounded pass—Design task sets, rubrics, references, review flow, and regression gates for a support-summary model. Put the input version, time window, and accountable owner in one place. Then link each judgment to an artifact. Finish with one validation action that can change the decision.

The evaluation set must cover high-value tasks, risky samples, and failure boundaries with reviewable scoring. The handoff should include an evidence index, assumptions that still need checking, and an action the next person can run without reconstructing the conversation. Plain work. It holds up.

Advanced use: turn one analysis into a maintained mechanism

The evaluation set must cover high-value tasks, risky samples, and failure boundaries with reviewable scoring.

Keep input versions and source IDs with every result. When requirements, code, environment, or data change, recompute only affected judgments and mark them changed, unchanged, or needs-review. Old conclusions are not new evidence.

A three-Skill chain

prompt-testing → llm-evaluation-design → llm-testing

HandoffPayloadReceiver check
Upstream to llm-evaluation-designSource versions, scope, risk, open itemsStaleness and conflicts
llm-evaluation-design to downstreamJudgments, evidence index, residual risk, tasksExecutability and ownership
Feedback to llm-evaluation-designRuns, defects, changed factsBaseline and regression scope

Hand over a summary, an evidence index, and locations for the source artifacts. That gives the receiver enough context and keeps the trail recoverable.

Team gates

GateCheckFailure action
llm-evaluation-design inputVersion, environment, sources, and ownerStop and list gaps
llm-evaluation-design artifactMaterial claims have basis, status, and impactReturn for evidence
llm-evaluation-design executionCommand, query, or verification path is repeatableClassify infrastructure or test issue
llm-evaluation-design decisionResidual risk has an accepter and dateDo not enter the next stage

Common traps

  1. Listing checks without input conditions, expected results, or evidence.
  2. Marking every finding high priority and removing the team’s ability to choose.
  3. Refusing to produce a bounded first pass, or presenting guesses as facts.
  4. Treating one success or one anomaly as long-term behavior while ignoring repeated trials and version changes.

Two practical questions

Can I start with incomplete input?

Yes. Produce a constrained first pass with known facts, assumptions, gaps, and the smallest validation action. Missing environment, data, or permission cannot support an execution claim.

When is human confirmation required?

The accountable owner must confirm scope trade-offs, risk acceptance, production actions, data permission, and release decisions. The Skill organizes evidence and options; it does not grant authority.

Run LLM Evaluation Design with one real artifact and keep the input, output, human edits, and verification evidence in the same work chain. That is what makes the next change cheaper to assess.

References

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