derive-tests

phuryn/product-engineering Testing & QA

derive-tests is a skill in phuryn/product-engineering, last changed 8 Nov 2026. It is instructions only: no scripts, no named hosts and no pre-approved tools.

From the author

'What should we test' or a coverage map: derive the coverage map and missing tests from docs and code; check mode reports staleness.

What it can touch

Instructions only

It is instructions only: no scripts, no named hosts and no pre-approved tools.

How much a skill can do, not whether it is risky.

Pattern check

Nothing flagged

That isn't proof the skill is harmless.

Commit bdb2389 · 11 Nov 2026

How the check works

Pattern check: nothing flagged

That isn't proof the skill is harmless.

QAI Index

58/QI

We rate every listed skill the same way, from 0 to 100.

A guide to compare by, not a verdict on the skill.

How it's scored

Install

Each tab says whether it installs commit bdb2389, the one we checked, or the latest version.

OpenCode also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.

Goose also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.

Windsurf (Devin Desktop) also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.

Zed also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.

Roo Code also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.

Factory Droid also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.

Junie also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.

Amp also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.

No install command here reaches Kiro. Copy the skill's folder into .kiro/skills/ in your project, or ~/.kiro/skills/ for all your projects. phuryn/product-engineering/ai-shipping/skills/derive-tests (opens in a new tab)

Antigravity also looks in .agents/skills/, so the Any agent steps reach it with This project. For All projects, see where Antigravity looks.

Cline also looks in .claude/skills/, so the Claude Code steps reach it with This project. For All projects, see where Cline looks.

No tab for your agent? Use Any agent for OpenCode, Goose, Windsurf (Devin Desktop), Zed, Roo Code, Factory Droid, Junie and Amp. With This project, Any agent also reaches Antigravity and Claude Code reaches Cline. Kiro needs the folder copied by hand.

Pinned to commit bdb2389, the one we checked.

From your project's root folder:

tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/phuryn/product-engineering.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin bdb2389c7636f6615c37fd66dd8518986284ec01 &&git -C "$tmp" sparse-checkout set -- ai-shipping/skills/derive-tests &&git -C "$tmp" checkout -q bdb2389c7636f6615c37fd66dd8518986284ec01 &&mkdir -p .claude/skills &&mkdir .claude/skills/derive-tests &&cp -R "$tmp"/ai-shipping/skills/derive-tests/. .claude/skills/derive-tests/ &&rm -rf "$tmp"

If Claude Code was already running and this created the skills folder, run /reload-skills.

Or install the ai-shipping plugin it ships in. Installs the latest version, not the one we checked. Installs everything in the plugin, including any hooks, MCP servers and scripts our check doesn't cover.

claude plugin marketplace add phuryn/product-engineering --scope project &&claude plugin install ai-shipping@product-engineering --scope project

Claude Code docs

Pinned to commit bdb2389, the one we checked.

Skills in the Claude apps belong to your account rather than to a project.

Make derive-tests.zip, with the skill folder at the top level:

tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/phuryn/product-engineering.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin bdb2389c7636f6615c37fd66dd8518986284ec01 &&git -C "$tmp" sparse-checkout set -- ai-shipping/skills/derive-tests &&git -C "$tmp" checkout -q bdb2389c7636f6615c37fd66dd8518986284ec01 &&out="$(mktemp -d)" &&cp -R "$tmp"/ai-shipping/skills/derive-tests "$out"/derive-tests &&(cd "$out" && zip -qr - derive-tests) > derive-tests.zip &&rm -rf "$tmp" "$out"

In Claude, open Customize > Skills, select +, then + Create skill > Upload a skill, and choose derive-tests.zip.

On Free, Pro and Max plans, turn on Code execution and file creation (Create and edit files in newer settings) under Settings > Capabilities.

Claude apps docs

Pinned to commit bdb2389, the one we checked.

From your project's root folder:

tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/phuryn/product-engineering.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin bdb2389c7636f6615c37fd66dd8518986284ec01 &&git -C "$tmp" sparse-checkout set -- ai-shipping/skills/derive-tests &&git -C "$tmp" checkout -q bdb2389c7636f6615c37fd66dd8518986284ec01 &&mkdir -p .agents/skills &&mkdir .agents/skills/derive-tests &&cp -R "$tmp"/ai-shipping/skills/derive-tests/. .agents/skills/derive-tests/ &&rm -rf "$tmp"

Codex picks up new skills on its own; restart it if this one does not appear.

Codex docs

Pinned to commit bdb2389, the one we checked.

From your project's root folder:

tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/phuryn/product-engineering.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin bdb2389c7636f6615c37fd66dd8518986284ec01 &&git -C "$tmp" sparse-checkout set -- ai-shipping/skills/derive-tests &&git -C "$tmp" checkout -q bdb2389c7636f6615c37fd66dd8518986284ec01 &&mkdir -p .cursor/skills &&mkdir .cursor/skills/derive-tests &&cp -R "$tmp"/ai-shipping/skills/derive-tests/. .cursor/skills/derive-tests/ &&rm -rf "$tmp"

Cursor docs

Pinned to commit bdb2389, the one we checked.

From your project's root folder:

tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/phuryn/product-engineering.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin bdb2389c7636f6615c37fd66dd8518986284ec01 &&git -C "$tmp" sparse-checkout set -- ai-shipping/skills/derive-tests &&git -C "$tmp" checkout -q bdb2389c7636f6615c37fd66dd8518986284ec01 &&mkdir -p .github/skills &&mkdir .github/skills/derive-tests &&cp -R "$tmp"/ai-shipping/skills/derive-tests/. .github/skills/derive-tests/ &&rm -rf "$tmp"

In a running Copilot CLI session, run /skills reload.

Or install it with gh skill, which also installs the commit we checked. Needs GitHub CLI 2.90 or later.

gh skill install phuryn/product-engineering ai-shipping/skills/derive-tests/SKILL.md@bdb2389c7636f6615c37fd66dd8518986284ec01 --agent github-copilot --scope project

Copilot & VS Code docs

Pinned to commit bdb2389, the one we checked.

From your project's root folder:

tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/phuryn/product-engineering.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin bdb2389c7636f6615c37fd66dd8518986284ec01 &&git -C "$tmp" sparse-checkout set -- ai-shipping/skills/derive-tests &&git -C "$tmp" checkout -q bdb2389c7636f6615c37fd66dd8518986284ec01 &&mkdir -p .gemini/skills &&mkdir .gemini/skills/derive-tests &&cp -R "$tmp"/ai-shipping/skills/derive-tests/. .gemini/skills/derive-tests/ &&rm -rf "$tmp"

In a running session, run /skills reload.

Or use Gemini CLI’s own installer. Installs the latest version, not the one we checked.

gemini skills install https://github.com/phuryn/product-engineering.git --path ai-shipping/skills/derive-tests --scope workspace

Gemini CLI docs

Pinned to commit bdb2389, the one we checked.

OpenCode, Goose, Windsurf (Devin Desktop), Zed, Roo Code, Factory Droid, Junie, Amp and Antigravity read .agents/skills in a project.

From your project's root folder:

tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/phuryn/product-engineering.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin bdb2389c7636f6615c37fd66dd8518986284ec01 &&git -C "$tmp" sparse-checkout set -- ai-shipping/skills/derive-tests &&git -C "$tmp" checkout -q bdb2389c7636f6615c37fd66dd8518986284ec01 &&mkdir -p .agents/skills &&mkdir .agents/skills/derive-tests &&cp -R "$tmp"/ai-shipping/skills/derive-tests/. .agents/skills/derive-tests/ &&rm -rf "$tmp"

Or use the skills CLI from skills.sh. Installs the latest version, not the one we checked. The skills CLI reports installs to skills.sh unless you set DISABLE_TELEMETRY=1.

npx skills@1.7.4 add phuryn/product-engineering --skill derive-tests

Agent Skills docs

Read SKILL.md first

MIT

Licence

530

Repo stars

Folder last changed

Publisher

Files

Checked

11 Nov 2026

What it can touch

From the files and frontmatter at commit bdb2389. This is how much a skill can do, not whether it is risky.

Instructions only

It is instructions only: no scripts, no named hosts and no pre-approved tools.

Pattern check

Pattern check: nothing flagged · commit bdb2389 · 11 Nov 2026

We checked every text file in this skill, at commit bdb2389 on 11 Nov 2026, against 45 published patterns such as download-and-run commands, hidden text and credential access. We don't run the skill, we don't read the web pages it points to, and we can't judge everything its instructions might lead an agent to do. In published tests, pattern checks like this one missed most malicious skills. Read the skill before you install it — especially anything it asks you to download or run.

How the check works Report an incorrect finding

Format check

Each agent reads SKILL.md a little differently. We check the file against each one's published rules; we don't run the skill in any agent.

Agent Skills specPasses with warnings
The open format from agentskills.io, held to the strictest version of each rule among the agents we check.
- Warning
  Fields outside the spec: argument-hint (read by Claude Code and VS Code). Uploads to the Claude apps and API, and the spec's validator, reject the file; most agents ignore these fields. O1
  Fix: Delete them for a portable skill, or keep them if you only target the agents that read them.
- Note
  The description doesn't say when to use the skill. D6
  Fix: Add a sentence such as "Use when …" naming the requests or files that should trigger it.
- Note
  There is no license field, so readers can't tell whether they may reuse the skill. O2
  Fix: Add license: with an SPDX name such as MIT or Apache-2.0, or the name of a bundled licence file.
Claude CodePasses
Claude apps & API uploadFails
Uploading to claude.ai or the Claude API, or packaging with Anthropic's script, accepts only the six spec fields and stops on anything else.
- Error
  Upload and packaging fail on fields outside the spec: argument-hint. O1
  Fix: Delete them, and keep your own data under metadata as text values.
OpenAI (Codex & API)Passes with warnings
Codex finds SKILL.md by its exact name and needs a description; OpenAI's Skills API checks the frontmatter against the spec and caps uploads.
- Warning
  Fields outside the spec: argument-hint. Codex ignores them; OpenAI doesn't say whether its upload accepts them. O1
  Fix: Delete them, or move your own data under metadata as text values.
VS Code & CopilotPasses

SKILL.md

Read SKILL.md on GitHub

Files

1 file

Path	Size
SKILL.md (opens in a new tab)	11.1 KB

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At a glance

What it can touch

Pattern check

QAI Index

Install

Claude Code

Claude apps

Codex

Cursor

Copilot & VS Code

Gemini CLI

Any agent

What it can touch

Pattern check

Format check

SKILL.md

Files

More from phuryn/product-engineering

Other Testing & QA skills