Risk Based Testing
petrkindlmann/qa-skills
Produce a risk matrix or heatmap that quantifies what could break by business impact × probability, runs failure mode analysis on the top items, and maps test coverage to risk zones.
Coverage-design method for qa-engineer — pyramid ratios per archetype, equivalence/boundary/property case selection, mutation score as the real coverage signal, and a flake-quarantine policy.
Install Test Strategy
$ npx skills add avelikiy/great_cto --skill test-strategy -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install avelikiy/great_cto test-strategy --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/avelikiy/great_cto.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/test-strategy .claude/skills/test-strategy && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "test-strategy" agent skill from https://github.com/avelikiy/great_cto/tree/main/skills/test-strategy into .claude/skills/test-strategy/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-strategy", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/avelikiy/great_cto/tree/main/skills/test-strategyType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add avelikiy/great_cto --skill test-strategy -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install avelikiy/great_cto test-strategy --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/avelikiy/great_cto.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/test-strategy .agents/skills/test-strategy && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "test-strategy" agent skill from https://github.com/avelikiy/great_cto/tree/main/skills/test-strategy into .agents/skills/test-strategy/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-strategy", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add avelikiy/great_cto --skill test-strategy -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install avelikiy/great_cto test-strategy --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/avelikiy/great_cto.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/test-strategy .cursor/skills/test-strategy && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "test-strategy" agent skill from https://github.com/avelikiy/great_cto/tree/main/skills/test-strategy into .cursor/skills/test-strategy/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-strategy", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/avelikiy/great_cto.git --path skills/test-strategy--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add avelikiy/great_cto --skill test-strategy -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install avelikiy/great_cto test-strategy --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/avelikiy/great_cto.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/test-strategy .gemini/skills/test-strategy && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "test-strategy" agent skill from https://github.com/avelikiy/great_cto/tree/main/skills/test-strategy into .gemini/skills/test-strategy/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-strategy", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install avelikiy/great_cto test-strategyInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add avelikiy/great_cto --skill test-strategy -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/avelikiy/great_cto.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/test-strategy .github/skills/test-strategy && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "test-strategy" agent skill from https://github.com/avelikiy/great_cto/tree/main/skills/test-strategy into .github/skills/test-strategy/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-strategy", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add avelikiy/great_cto --skill test-strategy -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install avelikiy/great_cto test-strategy --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/avelikiy/great_cto.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/test-strategy .opencode/skills/test-strategy && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "test-strategy" agent skill from https://github.com/avelikiy/great_cto/tree/main/skills/test-strategy into .opencode/skills/test-strategy/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-strategy", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
test-strategy- GitHub stars
- 102
- Token cost
- ~1k tokens
- SKILL.md length
- 389 words
- Files
- 1
- Skills in repo
- 27
- Repo updated
- First seen
- Licence
- MIT
At a glance
Coverage-design method for qa-engineer — pyramid ratios per archetype, equivalence/boundary/property case selection, mutation score as the real coverage signal, and a flake-quarantine policy.
- Works in 4 steps: Pyramid ratio — pick by archetype (not… → Case selection — equivalence / boundary… → Mutation score — the only coverage that… → …
- Tasks that involve Test strategy
- SKILL.md covers 1. Pyramid ratio — pick by…, 2. Case selection —…, 3. Mutation score — the only… and 4. Flake quarantine — a flaky…, plus 1 more section
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Test Strategy is an agent skill from avelikiy/great_cto. Coverage-design method for qa-engineer — pyramid ratios per archetype, equivalence/boundary/property case selection, mutation score as the real coverage signal, and a flake-quarantine policy. Turns "coverage is 90%" (a number with no method) into a defensible test plan. Emits TEST-STRATEGY-{slug}.md, which the QA gate checks exists.
Its SKILL.md is about 1k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
It sits in Testing & QA, covering Test strategy, QA and bug reports and Test generation. The repository describes itself as: You already have the agent. This is everything around it. greatcto runs Claude Code as a pipeline of 70 specialist agents — an independent model checks each stage before the next… The licence is MIT.
When your agent uses it
- Tasks that involve Test strategy
- Tasks that involve QA and bug reports
- Tasks that involve Test generation
Example prompts
- “coverage is 90%”
- “/test-strategy”
Requirements
- Pre-approved tools (allowed-tools): Read, Write, Grep, Glob, Bash
Workflow steps
4 steps, taken from the step headings in SKILL.md.
What it can do on your machine
Read from SKILL.md and the folder at commit 97dd037. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves these tools, so the agent can use them without asking each time:
ReadWriteGrepGlobBash
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Test Strategy loads about 1k tokens when it runs. Until then it costs about 87 tokens; SKILL.md has 389 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check: notes
The automated check noted patterns worth knowing about, such as sudo or a known installer.
- NotePre-approves every shell command (allowed-tools: Bash)SKILL.md
allowed-tools: Read, Write, Grep, Glob, Bash
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from avelikiy/great_cto at commit 97dd037, republished under its MIT licence (© avelikiy). 389 words, ~1,018 tokens.
Download SKILL.mdSave it as
.claude/skills/test-strategy/SKILL.md (or your agent's skills folder).- name
- test-strategy
- description
- Coverage-design method for qa-engineer — pyramid ratios per archetype, equivalence/boundary/property case selection, mutation score as the real coverage signal, and a flake-quarantine policy. Turns "coverage is 90%" (a number with no method) into a defensible test plan. Emits TEST-STRATEGY-{slug}.md, which the QA gate checks exists.
- allowed-tools
- Read, Write, Grep, Glob, Bash
- when_to_use
- Apply when: - qa-engineer is planning tests for a medium/large feature (>1 file, real behaviour risk) - a coverage % is being reported and you need to know…
- effort
- medium
- paths
- tests/**, docs/qa-reports/**
test-strategy
Coverage % is a number with no method. This skill makes the QA plan defensible: what to test, why that set, and a real signal that the tests bite.
qa-engineer emits docs/qa-reports/TEST-STRATEGY-{slug}.md capturing the four
decisions below; the QA gate checks the file exists for medium/large features.
1. Pyramid ratio — pick by archetype (not by reflex)
The right unit:integration:e2e mix depends on where the risk lives.
| Archetype | unit | integration | e2e | why |
|---|---|---|---|---|
| library / devtools / cli | 80% | 15% | 5% | logic-dense, few I/O seams |
| web-app / saas | 60% | 30% | 10% | request→db→render seams dominate |
| commerce / fintech / marketplace | 50% | 35% | 15% | money paths need cross-component proof |
| data-platform / streaming | 45% | 45% | 10% | correctness lives in pipelines, not units |
| ai-system / agent-product | 50% | 20% | 10% + evals 20% | behaviour is the contract → eval set (see [[decision-eval]]) |
State the chosen ratio in TEST-STRATEGY and justify any deviation.
2. Case selection — equivalence / boundary / property
Don't enumerate inputs; partition them.
- Equivalence classes — one representative per class of behaviour (valid, invalid, empty, max). Testing 5 valid ids ≠ testing 5 classes.
- Boundaries — the bug lives at the edge: 0, 1, n-1, n, n+1, off-by-one, empty, overflow, the threshold itself.
- Property-based — for pure/transform logic, assert invariants over generated input (round-trip
decode(encode(x))===x, idempotency, ordering) instead of hand-picked cases. Use fast-check / Hypothesis where the logic warrants it.
Show full SKILL.md (180 more words)Show less
3. Mutation score — the only coverage that proves the tests bite
Line/branch coverage proves code ran, not that a test would fail if it broke. Mutation testing (Stryker / mutmut / cargo-mutants) flips operators/conditions and checks a test catches it. A "90% covered" module with 30% mutation score has assertion-free tests. Target: mutation score ≥ 60% on changed logic-dense files; report it in TEST-STRATEGY when the change is logic-heavy. Coverage % is the cheap proxy; mutation score is the truth.
4. Flake quarantine — a flaky test is worse than no test
A test that fails ~randomly trains the team to ignore red. Policy:
- A test that fails non-deterministically is quarantined (skipped + tracked in a Beads bug), not left to rot the signal.
- Quarantine is time-boxed: a bug with an owner and a deadline, not
it.skipforever. - Root-cause before re-enabling (shared state, timing, real network, ordering).
- This is the same discipline the eval runner needs (see the eval
flakyflag intests/eval/runner.mjs— stddev > 0.1 is a flake signal).
Output: TEST-STRATEGY-{slug}.md
# TEST-STRATEGY-{slug}
- Archetype + chosen pyramid ratio (+ justification for any deviation)
- Equivalence classes & boundaries enumerated per changed unit
- Property-based candidates (which logic, which invariants)
- Mutation-score target + result (for logic-dense changes)
- Quarantine list (flaky tests + their tracking bug)Done = the plan answers "why THIS set of tests", not just "how much is covered".
© avelikiy, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
Just SKILL.md in skills/test-strategy of avelikiy/great_cto.
Open the folder on GitHubat commit 97dd037
Compare with similar skills
Test Strategy next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Test Strategy this skillavelikiy/great_cto | 102 | — | ~1k | Automated safety check: Notes | MIT | |
| Risk Based Testingpetrkindlmann/qa-skills | 170 | — | ~5.3k | Automated safety check: Pass | MIT | |
| Senior QAnicepkg/auto-company | 195 | 3 repos | ~1.1k | Automated safety check: Notes | None | |
| QA Manual Istqbfugazi/test-automation-skills-agents | 249 | — | ~3.6k | Automated safety check: Pass | MIT | |
| Test Planquran/quran.com-frontend-next | 1.9k | — | ~1.4k | Automated safety check: Pass | None | |
| Bmad Testarch Test Designbmad-code-org/bmad-method-test-architecture-enterprise | 105 | 3 repos | ~1.4k | Automated safety check: Pass | Custom licence |
Similar skills
Senior QA
nicepkg/auto-company
Comprehensive QA and testing skill for quality assurance, test automation, and testing strategies for ReactJS, NextJS, NodeJS applications.
QA Manual Istqb
fugazi/test-automation-skills-agents
Create QA artifacts from requirements: test plans, test conditions/cases, bug reports, regression suites, traceability, and exploratory charters.
Test Plan
quran/quran.com-frontend-next
Generates a comprehensive testing plan based on the current branch changes or a specific PR.
Bmad Testarch Test Design
bmad-code-org/bmad-method-test-architecture-enterprise
Create system-level or epic-level test plans. An agent skill from bmad-code-org/bmad-method-test-architecture-enterprise.
Designing Tests
CloudAI-X/opencode-workflow
Guides test strategy, TDD/BDD approaches, test coverage planning, and testing best practices.
More from avelikiy/great_cto
All 27 skills in this repoAnyDesign Design Analyzer
avelikiy/great_cto
Analyzes a screenshot, website or Figma file and writes a `design.md` with its token system, component inventory and reconstruction notes, or an `element.md` for one element.
Opportunity Solution Tree
avelikiy/great_cto
Builds an Opportunity Solution Tree that links one measurable outcome to customer opportunities, candidate solutions and experiments.
Outcome-Focused Roadmap Rewriter
avelikiy/great_cto
Rewrites a feature-list roadmap into outcome statements that name the customer segment, the result they get and the business impact, grouped into themes.
Exposed Secret Rotation
avelikiy/great_cto
Turns a leaked key, token or password into one tracked rotation task the moment it's spotted, instead of a reminder repeated every session.
Skeptical Triage
avelikiy/great_cto
Runs a three-round self-challenge plus an arbiter over high-stakes findings, so false positives from reviews, audits and flaky-test verdicts do not become blockers.
Aesthetic Instrument
avelikiy/great_cto
greatcto's own committed aesthetic — the instrument panel. An agent skill from avelikiy/great_cto.
Related
Categories
Questions about Test Strategy
What does Test Strategy do?
Coverage-design method for qa-engineer — pyramid ratios per archetype, equivalence/boundary/property case selection, mutation score as the real coverage signal, and a flake-quarantine policy. Test Strategy is an agent skill from avelikiy/great_cto. Coverage-design method for qa-engineer — pyramid ratios per archetype, equivalence/boundary/property case selection, mutation score as the real coverage signal, and a flake-quarantine policy.
When should I use Test Strategy?
Test Strategy fits situations like: tasks that involve Test strategy; tasks that involve QA and bug reports; tasks that involve Test generation.
How do I install Test Strategy in Claude Code?
Run `npx skills add avelikiy/great_cto --skill test-strategy -a claude-code`. Or copy the skill folder (skills/test-strategy in avelikiy/great_cto) into .claude/skills/test-strategy in your project. Claude Code loads it when a task matches its description.
How do I install Test Strategy in Codex?
Run `npx skills add avelikiy/great_cto --skill test-strategy -a codex`. Or copy the skill folder (skills/test-strategy in avelikiy/great_cto) into .agents/skills/test-strategy in your project. Codex loads it when a task matches its description.
Can I use Test Strategy in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add avelikiy/great_cto --skill test-strategy -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/test-strategy, .gemini/skills/test-strategy, .github/skills/test-strategy and .opencode/skills/test-strategy in your project.
What does Test Strategy need to run?
SKILL.md names no scripts, command-line tools or credentials: Test Strategy is instructions for the agent only. Its frontmatter pre-approves these tools: Read, Write, Grep, Glob, Bash.
Does Test Strategy access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Test Strategy safe to install?
Our automated static check of SKILL.md found notes only (pre-approves every shell command (allowed-tools: bash)), nothing it rates as a warning. It is not a guarantee. Review the folder before installing.
What licence does Test Strategy use?
Test Strategy is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Test Strategy use?
About 1k tokens (SKILL.md is roughly 4.1k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Test Strategy?
Skills that share tags, products or a category with Test Strategy: Risk Based Testing (petrkindlmann/qa-skills, 170 stars), Senior QA (nicepkg/auto-company, 195 stars), QA Manual Istqb (fugazi/test-automation-skills-agents, 249 stars) and Test Plan (quran/quran.com-frontend-next, 1.9k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Test Strategy?
avelikiy (a GitHub user) maintains it in avelikiy/great_cto, which has 102 GitHub stars. The repository holds 27 skills in this directory. The repository was last updated on October 9, 2026.
Source: avelikiy/great_cto on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.