Borrowing it
Nothing to install: this file belongs to nicograef/handbook. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/nicograef/handbook/main/.claude/skills/test-quality/SKILL.mdgit clone --depth 1 https://github.com/nicograef/handbookWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/nicograef/handbook/test-quality)<a href="https://agentmods.dev/skills/nicograef/handbook/test-quality"><img src="https://agentmods.dev/badge/skills/nicograef/handbook/test-quality.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00044 | $0.00861 |
| Opus 5 | $0.00022 | $0.00430 |
| Sonnet 5 | $0.00009 | $0.00172 |
| Haiku 4.5 | $0.00004 | $0.00086 |
Grade A, and why
test-quality scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test Quality Review
Workflow
Step 1 — Discover
- List the test files in a compact inventory table: file → test count → framework.
- Note any test helpers, fixtures, or shared setup files.
- Ask the user whether to limit scope to specific packages or files, before proceeding.
Step 2 — Audit
- Evaluate every test file.
- Assign each test exactly one tag: Keep, Refactor, Delete, or Merge.
- Apply the decision rules and anti-pattern catalog in anti-patterns.md.
- Group findings by file.
- Do not make changes yet.
Step 3 — Report
Present the summary to the user before touching any code.
- Group the tags by file, in this shape:
File: src/checkout/checkout.test.ts (12 tests)
Keep 4 — [list test names]
Refactor 5 — [list test names + 1-line reason]
Delete 2 — [list test names + 1-line reason]
Merge 1 — [list test names + target]
File: src/cart/cart.test.ts (8 tests)
...
Total: 20 tests → 17 tests after changes
- Fields — Keep and Merge list test names; Merge adds the target.
- Fields — Refactor and Delete add a one-line reason per test.
- Delete and Merge tags follow the report shape rules.
- Explain the biggest quality wins after the report.
- Ask for explicit confirmation before proceeding.
- Update any tag the user disagrees with, before proceeding.
- Gate — do not start Step 4 until the user confirms.
Step 4 — Refactor
Work through changes one file at a time.
- Apply Merge first (reduces total test count, simplifies subsequent work)
- Apply Refactor next (rewrite tests to use public interface only)
- Apply Delete last (already confirmed in the Step 3 report)
- Remove dead test helpers and fixtures that are no longer referenced
- Clean up imports left orphaned by deleted tests
- Preserve mocks at true system boundaries (HTTP, email, time, randomness). Prefer a real test DB, mocking the driver only when none is available.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago Changed · -5 lines f0acbbcc6ed9
- 6d ago First seen · 98 lines · 44 tokens per session scan A 4d3e30f5c2c9
test-quality is a skill published in the GitHub repository nicograef/handbook (2 stars, last pushed 3d ago), licensed MIT. It adds 44 tokens to every session and 861 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
adversarial-reviewer
Adversarial code review that assumes bugs exist and hunts for them. Use when asked to review code, find bugs, audit for correctness, stress-test a PR, or when someone says "tear this apart" or "what's wrong with this". Give no benefit of the doubt — every line is guilty until proven innocent.
go-testing
Trigger: Go tests, go test coverage, Bubbletea teatest, golden files. Apply focused Go testing patterns.
semgrep-rule-variant-creator
Creates language variants of existing Semgrep rules. Use when porting a Semgrep rule to specified target languages. Takes an existing rule and target languages as input, produces independent rule+test directories for each language.
brooks-sweep
Full-sweep mode: runs a unified analysis across all quality dimensions — code decay, architecture, tech debt, and test quality — then applies fixes directly to the codebase. Safe changes are auto-applied; risky changes are confirmed before execution. Drawing on twelve classic engineering books. Triggers when: user…
include-test-files-that-assert-on-behavior-being-changed-in-decl
When delegating a task affected by this skill, include.
qa-frontend
Internal PostHog developer frontend/browser QA skill. Use only when a PostHog developer explicitly asks to run frontend QA, browser-test a PR, verify a UI flow against the local PostHog stack, use qa-frontend, or QA current frontend changes with browser/runtime evidence. Do not use for generic code review, PR review…