
Skill
braintrust-plan-agent-eval
plan evaluation workflows for LLM applications
Description
Plan an evaluation workflow for an LLM application or agent by identifying the product decision, expected behavior, target population, evidence, datasets, scorers, validation, analysis, and release criteria. Use for broad or early-stage requests such as "help me evaluate this agent," "design an eval strategy," "where do we start with evals," or when a user describes an agent, a product goal, or a production failure without naming an eval artifact. Do not use when the user already names a behavior spec, dataset, sample size, scorer, human review, experiment, analysis, release gate, or report — route to that skill.
SKILL.md
Plan an agent eval
Contract: references/interaction-contract.md. Calibration, templates, provenance: references/lifecycle-inventory.md.
Trigger
- Broad eval requests naming no artifact and no stage.
- An agent, goal, or incident described with no eval scaffolding.
- A stalled effort: metrics exist, but nobody can say which decision they serve.
Do
- Restate the product decision in one sentence. Every downstream choice serves it.
- Inventory existing artifacts against the staged lifecycle in
references/lifecycle-inventory.md, labeling each stageConfirmed/Assumed/Needs decision/Not yet measurable. - Name the earliest missing artifact, not the most interesting one. A gap upstream makes every downstream number uninterpretable.
- Check the two prerequisites teams skip: is the system instrumented well enough to reconstruct a failure, and can anyone state what "good" means?
- Hand off the one stage to do next, its concrete first action, and the reason it blocks the rest.
Avoid
- Do not walk the whole lifecycle in one pass or produce every artifact at once.
- Do not intercept a request that already names an artifact.
- Do not propose a public benchmark as the starting point; it measures its own construct.
- Do not manufacture process for a low-stakes, reversible decision — say so instead.
Check
- Decision stated; construct and population named or flagged unknown.
- Every lifecycle stage carries a status label.
- Exactly one recommended next stage, with its blocking reason.
- Assumptions listed separately from confirmed facts.
Risk
- A broad router over-triggers: it will invent process for someone who asked a narrow question. Whenever the request already names an artifact, that artifact's own stage owns the work.
- The earliest gap is usually unglamorous — instrumentation, population definition — and gets skipped for scorer work.
- Plans go stale as soon as the product changes. Date it; it is a map, not a contract.
Braintrust
Read the project before asking — most planning questions answer themselves. Which of the four
objects (references/platform-mechanics.md §1) already exist, and in what state? Are datasets
versioned (§3)? Are scorers named consistently across experiments, or renamed per run (§5)?
Do experiments record independent variables in metadata, or only scores (§4)? Is anything
scoring production traffic?
Each "no" is a lifecycle gap. Record it in the inventory rather than acting on it here — and note that the §3 and §4 gaps are the ones with no retroactive fix, which usually makes them the earliest missing artifact even when they are not the most interesting one.
More skills from the eval-library repository
View all 24 skillsbraintrust-analyze-eval-experiment
analyze LLM and agent eval experiments
Aug 20AnalysisBraintrustEvalsLLM +1braintrust-attribute-multi-variable-change
attribute performance changes to multiple variables
Aug 20AnalysisBraintrustEvalsLLM +1braintrust-build-eval-dataset
create and manage LLM eval datasets
Aug 20AgentsBraintrustDatasetsEvals +1braintrust-define-eval-objective
define LLM evaluation objectives
Aug 20BraintrustEvalsLLMProduct Management +1braintrust-define-eval-release-gate
configure release gates for LLM applications
Aug 20AgentsBraintrustCI/CDEvals +1braintrust-deploy-evaluator
deploy evaluators to Braintrust
Aug 20BraintrustDeploymentEvals
More from Braintrust
View publishertroubleshoot-braintrust-mcp
configure and troubleshoot Braintrust MCP servers
braintrust-claude-plugin
Jul 12BraintrustDebuggingMCPbraintrust-design-eval-experiment
design controlled LLM eval experiments
eval-library
Aug 20BraintrustEvalsExperimentsLLM +1braintrust-design-eval-instrumentation
design trace and evaluation dataset schemas
eval-library
Aug 20BraintrustDatasetsEvalsObservability +1braintrust-design-eval-metric-bundle
create multi-objective evaluation metric bundles
eval-library
Aug 20AgentsBraintrustEvalsLLM +1braintrust-design-human-eval-review
design human evaluation and review workflows
eval-library
Aug 20AgentsBraintrustDatasetsEvals +1braintrust-discover-agent-failures
identify and classify agent failure modes
eval-library
Aug 20AgentsBraintrustDebuggingEvals +1