LLM Evaluation Engineering
The methodology that catches regressions before users do.
5
Skills
5
Adapters
2
Worked examples
What you'll be able to do
Concrete outcomes, not vague promises.
You're shipping an LLM feature
You added a new prompt. You want to know if quality went up or down. No eval system, just vibes and a few manual checks.
You're evaluating a new model
GPT-5 just dropped. You want to know if it's better than Sonnet for your use case. The vendor says yes. Your gut says maybe.
You're scaling AI features
Three teams, six features, dozens of prompts. You can't manually review every change. Quality is drifting.
Built for
If any of these are you, this is for you.
Why this playbook works
Three things that make this different from a wall of prompts.
The eval funnel
Deterministic first (cheap, fast, reliable). LLM-as-judge second (expensive, needs calibration). Human review last (ground truth). Every eval system should walk the funnel.
Golden sets from real failures
The best golden sets are built from real prod failures, not imagined test cases. The pack teaches how to harvest failures into your eval set.
Eval-first PRs
Run evals before merging. Compare to the prior baseline. Catch regressions before they reach users. The workflow, not the tool.
Quick start
Drop the package into your project and start using the commands.
What's in the box
- 5 skillseval funnel, design, scorers, judge, workflow
- 5 tool adapterspi-agent, Claude Code, Cursor, Cline, generic
- 2 worked exampleseval design + regression detection
- Methodologyvendor-agnostic
- Calibration patternsfor LLM-as-judge
- Golden set constructionfrom real failures
Everything in the pack
What you get the moment your payment clears.
Adapters included
These skills were authored for pi-agent, but we include drop-in adapters for the major AI coding tools.
| Tool | Adapter location | What you get |
|---|---|---|
| pi-agent | adapters/pi-agent/ | SKILL.md drop-in |
| Claude Code | adapters/claude-code/ | .claude/commands/*.md + CLAUDE.md |
| Cursor | adapters/cursor/ | .cursorrules rule sets |
| Cline / Continue | adapters/cline/ | System-prompt rules |
| Aider / generic | adapters/generic/ | INSTRUCTIONS.md snippets |
Same playbook, different packaging. The adapters translate the methodology into the format each tool expects. Install once, swap agents without re-learning the method.
Full documentation
Everything in the package, every prop, every pattern.
LLM Evaluation Engineering
The methodology that catches regressions before users do.
Built and battle-tested. 5 skills covering the eval mindset, deterministic scorers, LLM-as-judge calibration, golden sets, and eval-driven development. Adapters for pi-agent, Claude Code, Cursor, Cline, and any tool that reads a system-prompt file.
What's Inside
| Skill | Purpose |
|---|---|
| llm-evaluation | Master orchestrator — the eval funnel, when to use what, the eval mindset |
| eval-design | Designing evals: what to measure, how to write criteria, golden set construction |
| deterministic-scorers | Non-LLM-as-judge: schema checks, regex, exact-match, citation-presence |
| llm-as-judge | When LLM judges make sense, calibration, prompt design, pitfalls |
| eval-driven-dev | Workflow: eval-first PRs, baseline tracking, regression detection |
Quick Start
# 1. Extract
tar -xzf llm-evaluation-0.1.0.tgz
cd llm-evaluation-0.1.0
# 2. Pick your agent host
ls adapters/
# pi-agent (recommended)
mkdir -p ~/.pi/agent/skills
cp -r skills/* ~/.pi/agent/skills/
# /reload in pi to pick them up
# Claude Code
mkdir -p .claude/commands
cp -r adapters/claude-code/commands/* .claude/commands/
cat adapters/claude-code/CLAUDE.md >> CLAUDE.md
The Core Idea
The single sentence that ties this whole pack together:
All you get from using prefab evals is you don't know what they actually do. — Hamel Husain
The pack teaches the eval funnel: deterministic checks first (cheap, fast, reliable), LLM-as-judge second (expensive, slower, needs calibration), human review last (slowest, most expensive, ground truth). Every eval system should walk the funnel — most ship the wrong way.
The 5 Skills in Detail
llm-evaluation — The orchestrator
- The eval funnel (deterministic → LLM → human)
- When to use what
- The eval-driven development loop
eval-design — What to measure
- Writing criteria that mean something
- Golden set construction from real failures
- Coverage: happy path, edge cases, adversarial cases
deterministic-scorers — The cheap layer
- Schema validation
- Exact-match, regex, substring
- Citation-presence, refusal detection
- These are the workhorses — use them first
llm-as-judge — The expensive layer
- When LLM judges make sense (quality, nuance)
- Calibration against human ground truth
- Prompt design for judges
- Bias mitigation
eval-driven-dev — The workflow
- Eval-first PRs (eval before feature)
- Baseline tracking
- Regression detection (vs prior baseline)
- CI integration
Adapters Included
Works in every major AI coding tool:
| Tool | Adapter location | What you get |
|---|---|---|
| pi-agent | adapters/pi-agent/ | SKILL.md drop-in |
| Claude Code | adapters/claude-code/ | .claude/commands/*.md + CLAUDE.md fragments |
| Cursor | adapters/cursor/ | .cursorrules rule sets |
| Cline / Continue | adapters/cline/ | System-prompt rules |
| Aider / generic | adapters/generic/ | INSTRUCTIONS.md snippets |
Updates
Free for life. Re-download for new scoring patterns, new LLM-as-judge techniques, new baseline tracking approaches.
What This Isn't
- Not a vendor replacement — works with Braintrust, LangSmith, Arize, Helicone
- Not eval-as-a-service — methodology you apply to your own evals
- Not prebuilt eval sets — teaches you to build your own from real failures
What's in the download
llm-evaluation-0.1.0/
├── README.md
├── OVERVIEW.md
├── METHODOLOGY.md
├── INSTALL.md
├── LICENSE.md
├── package.json
├── skills/ ← 5 SKILL.md files
│ ├── llm-evaluation/
│ ├── eval-design/
│ ├── deterministic-scorers/
│ ├── llm-as-judge/
│ └── eval-driven-dev/
├── adapters/ ← drop-in for AI coders
│ ├── pi-agent/
│ ├── claude-code/
│ ├── cursor/
│ ├── cline/
│ └── generic/
├── examples/ ← 2 worked examples
└── docs/ ← diagrams + decision trees
Common questions
Things people ask before buying.
Is this a Braintrust / LangSmith / Helicone replacement?
No. The pack is methodology — what to measure, how to design evals, how to detect regressions. The vendors are infrastructure — they run the evals. Use both: this pack for the playbook, your vendor for execution.
How is this different from Hamel Husain's Maven course?
Hamel's course is the gold standard. This pack distills the same methodology into a SKILL.md bundle you can drop into your agent. The course is 6 weeks of video; the pack is the same playbook, condensed, agent-loadable.
I don't have any evals yet. Where do I start?
Start with eval-design. It teaches you to write criteria, build a golden set from real failures, and pick the right granularity. From there, deterministic-scorers first (cheap), LLM-as-judge second (calibrate against human).
£40 — lifetime
One purchase. Yours forever.
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