How do I install the Eval Spec Vs Build skill?

Run npx skillmds@latest add https-deeplearning-ai/eval-spec-vs-build in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Eval Spec Vs Build safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Eval Spec Vs Build?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Eval Spec Vs Build free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Eval Spec Vs Build?

https-deeplearning-ai (@https-deeplearning-ai) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Eval Spec Vs Build by https-deeplearning-ai

Name: Eval Spec Vs Build
Author: https-deeplearning-ai

Eval Spec Vs Build

Scores how faithfully a recorded build run followed its spec.md, in the spec-build-lab. Use this skill ANY time the user asks to evaluate, score, check, judge, assess, or compare a specific build run AGAINST THE SPEC — including phrasings like "evaluate run-02 against the spec", "score run-02 against the spec", "did the build follow the spec", "did run-02 implement the spec", "spec fidelity check on run-NN", "how closely did run-02 follow spec.md", "run a spec-vs-build eval", "evaluate the spec adherence of the latest run", or "/eval-spec-vs-build run-NN". Reads the per-run snapshot evals/<run>/spec.md (NOT the live spec.md) and the contents of builds/<run>/, then writes evals/<run>/spec-vs-build.md. Requires an explicit run-NN; if none is given, list the runs in builds/ and ASK which one — never default. Do NOT use this skill to evaluate against course materials — that's /eval-materials-vs-build, a different reference and different question.

File contents

eval-spec-vs-build

Compare a recorded run's app against the spec snapshot it was built from. Spec fidelity only. Course alignment is /eval-materials-vs-build.

Steps

Verify cwd is a course folder. Confirm spec.md, materials/, builds/, evals/ exist. Refuse otherwise: "Run /eval-spec-vs-build from inside a course folder."
Require a run. If $ARGUMENTS is empty:
```
ls -1 builds/ 2>/dev/null | grep -E '^run-[0-9]+$' | sort
```
List those runs and ask the user: "Which run should I evaluate? Pick one — I won't default to the latest." Stop until they answer.
Validate the run. Confirm evals/$ARGUMENTS/spec.md (the snapshot) exists and builds/$ARGUMENTS/ is a non-empty directory. Refuse otherwise. The report reflects whatever the build folder contains — evaluating an in-progress run is fine; just re-run after the build finishes for a clean score.
Read the inputs.
- Snapshot spec: evals/$ARGUMENTS/spec.md (NOT the top-level spec.md — that may have been regenerated since this run).
- Build: walk builds/$ARGUMENTS/ (skip node_modules, .venv, dist, build, .git, and anything matching its own .gitignore).
Produce the report at evals/$ARGUMENTS/spec-vs-build.md with sections:
- Summary — one-paragraph verdict.
- Coverage matrix — each spec section → present / partial / missing, with file references into builds/$ARGUMENTS/.
- Divergences — things the build did that the spec did not specify.
- Missing — things the spec specified that the build did not do.
- Score — your judgment on a 0–10 scale, with reasoning.
Report the path written, then hand off. After echoing the report path, tell the user: "Spec-fidelity report written. The companion eval is /eval-materials-vs-build $ARGUMENTS — different reference, different question (course alignment, not spec fidelity). Say 'go ahead' to run it next, or skip if you've already done it."

Don't

Don't read materials/ — that's the other eval. Mixing them defeats the point of having two.
Don't read the top-level spec.md — always the per-run snapshot.
Don't pick a default run. List the runs in builds/ and ask the user which one.

---name: eval-spec-vs-builddescription: Scores how faithfully a recorded build run followed its spec.md, in the spec-build-lab. Use this skill ANY time the user asks to evaluate, score, check, judge, assess, or compare a specific build run AGAINST THE SPEC — including phrasings like "evaluate run-02 against the spec", "score run-02 against the spec", "did the build follow the spec", "did run-02 implement the spec", "spec fidelity check on run-NN", "how closely did run-02 follow spec.md", "run a spec-vs-build eval", "evaluate the spec adherence of the latest run", or "/eval-spec-vs-build run-NN". Reads the per-run snapshot evals/<run>/spec.md (NOT the live spec.md) and the contents of builds/<run>/, then writes evals/<run>/spec-vs-build.md. Requires an explicit run-NN; if none is given, list the runs in builds/ and ASK which one — never default. Do NOT use this skill to evaluate against course materials — that's /eval-materials-vs-build, a different reference and different question.---# eval-spec-vs-buildCompare a recorded run's app against the spec snapshot it was built from.**Spec fidelity only.** Course alignment is `/eval-materials-vs-build`.## Steps1. **Verify cwd is a course folder.** Confirm `spec.md`, `materials/`, `builds/`, `evals/` exist. Refuse otherwise: "Run /eval-spec-vs-build from inside a course folder."2. **Require a run.** If `$ARGUMENTS` is empty: ```bash ls -1 builds/ 2>/dev/null | grep -E '^run-[0-9]+$' | sort ``` List those runs and ask the user: "Which run should I evaluate? Pick one — I won't default to the latest." Stop until they answer.3. **Validate the run.** Confirm `evals/$ARGUMENTS/spec.md` (the snapshot) exists and `builds/$ARGUMENTS/` is a non-empty directory. Refuse otherwise. The report reflects whatever the build folder contains — evaluating an in-progress run is fine; just re-run after the build finishes for a clean score.4. **Read the inputs.** - Snapshot spec: `evals/$ARGUMENTS/spec.md` (NOT the top-level `spec.md` — that may have been regenerated since this run). - Build: walk `builds/$ARGUMENTS/` (skip node_modules, .venv, dist, build, .git, and anything matching its own .gitignore).5. **Produce the report at `evals/$ARGUMENTS/spec-vs-build.md`** with sections: - **Summary** — one-paragraph verdict. - **Coverage matrix** — each spec section → present / partial / missing, with file references into `builds/$ARGUMENTS/`. - **Divergences** — things the build did that the spec did not specify. - **Missing** — things the spec specified that the build did not do. - **Score** — your judgment on a 0–10 scale, with reasoning.6. **Report the path written, then hand off.** After echoing the report path, tell the user: "Spec-fidelity report written. The companion eval is /eval-materials-vs-build $ARGUMENTS — different reference, different question (course alignment, not spec fidelity). Say 'go ahead' to run it next, or skip if you've already done it."## Don't- Don't read `materials/` — that's the *other* eval. Mixing them defeats the point of having two.- Don't read the top-level `spec.md` — always the per-run snapshot.- Don't pick a default run. List the runs in `builds/` and ask the user which one.

Frequently asked questions