Test Guidelines
getsentry/sentry-dart
Enforce Sentry Dart/Flutter SDK test conventions for naming, structure, and fixtures.
Red-green-refactor development methodology requiring verified test coverage.
Install Test Driven Development
$ npx skills add aiskillstore/marketplace --skill test-driven-development -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install aiskillstore/marketplace test-driven-development --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/aiskillstore/marketplace.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/codingcossack/test-driven-development .claude/skills/test-driven-development && 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-driven-development" agent skill from https://github.com/aiskillstore/marketplace/tree/main/skills/codingcossack/test-driven-development into .claude/skills/test-driven-development/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-driven-development", 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/aiskillstore/marketplace/tree/main/skills/codingcossack/test-driven-developmentType 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 aiskillstore/marketplace --skill test-driven-development -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install aiskillstore/marketplace test-driven-development --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/aiskillstore/marketplace.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/codingcossack/test-driven-development .agents/skills/test-driven-development && 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-driven-development" agent skill from https://github.com/aiskillstore/marketplace/tree/main/skills/codingcossack/test-driven-development into .agents/skills/test-driven-development/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-driven-development", 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 aiskillstore/marketplace --skill test-driven-development -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install aiskillstore/marketplace test-driven-development --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/aiskillstore/marketplace.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/codingcossack/test-driven-development .cursor/skills/test-driven-development && 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-driven-development" agent skill from https://github.com/aiskillstore/marketplace/tree/main/skills/codingcossack/test-driven-development into .cursor/skills/test-driven-development/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-driven-development", 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/aiskillstore/marketplace.git --path skills/codingcossack/test-driven-development--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 aiskillstore/marketplace --skill test-driven-development -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install aiskillstore/marketplace test-driven-development --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/aiskillstore/marketplace.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/codingcossack/test-driven-development .gemini/skills/test-driven-development && 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-driven-development" agent skill from https://github.com/aiskillstore/marketplace/tree/main/skills/codingcossack/test-driven-development into .gemini/skills/test-driven-development/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-driven-development", 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 aiskillstore/marketplace test-driven-developmentInstalls 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 aiskillstore/marketplace --skill test-driven-development -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/aiskillstore/marketplace.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/codingcossack/test-driven-development .github/skills/test-driven-development && 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-driven-development" agent skill from https://github.com/aiskillstore/marketplace/tree/main/skills/codingcossack/test-driven-development into .github/skills/test-driven-development/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-driven-development", 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 aiskillstore/marketplace --skill test-driven-development -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install aiskillstore/marketplace test-driven-development --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/aiskillstore/marketplace.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/codingcossack/test-driven-development .opencode/skills/test-driven-development && 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-driven-development" agent skill from https://github.com/aiskillstore/marketplace/tree/main/skills/codingcossack/test-driven-development into .opencode/skills/test-driven-development/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-driven-development", 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-driven-development- GitHub stars
- 430
- Token cost
- ~1.9k tokens
- SKILL.md length
- 709 words
- Files
- 4 (incl. references)
- Skills in repo
- 1,108
- Repo updated
- First seen
- Licence
- None found
At a glance
Red-green-refactor development methodology requiring verified test coverage.
- Works in 5 steps: Write tests that capture current… → Run tests, observe actual outputs → Update assertions to match reality… → …
- Feature implementation
- SKILL.md covers The Iron Law, Red-Green-Refactor Cycle, Good Tests and Example: Bug Fix, plus 9 more sections
- Calls npm
What it does
Test Driven Development is an agent skill from aiskillstore/marketplace. Red-green-refactor development methodology requiring verified test coverage. Use for feature implementation, bugfixes, refactoring, or any behavior changes where tests must prove correctness.
Its SKILL.md is about 1.9k tokens, which your agent loads only when the skill is triggered. The skill folder holds 4 other files, including reference files (for example `references/tdd-philosophy.md`, `references/testing-anti-patterns.md` and `skill-report.json`).
It sits in Testing & QA, covering Test-driven development, Refactoring and Test coverage. The repository describes itself as: Security-audited skills for Claude, Codex & Claude Code. One-click install, quality verified.
When your agent uses it
- Feature implementation
- Any behavior changes where tests must prove correctness
Example prompts
- “/test-driven-development”
Workflow steps
5 steps, taken from the first numbered list in SKILL.md.
- Write tests that capture current behavior (even if "wrong")
- Run tests, observe actual outputs
- Update assertions to match reality (these are "golden masters")
- Now you have a safety net for refactoring
- Apply TDD for new behavior changes
What it can do on your machine
Read from SKILL.md and the folder at commit ad8daf7. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
Shell commands in SKILL.md call:
npm
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md. Its commands use npm, which can reach the network depending on how they are called.
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 Driven Development loads about 1.9k tokens when it runs, and up to ~4.7k if it reads all its reference files. Until then it costs about 54 tokens; SKILL.md has 709 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 passed
The automated check found no risky patterns in SKILL.md.
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
Without a licence we can't republish the file, so here is its outline and opening line. It has 709 words (~1,877 tokens).
“Write test first. Watch it fail. Write minimal code to pass. Refactor.”
- name
- test-driven-development
Files
SKILL.md and 3 other files (references) in skills/codingcossack/test-driven-development of aiskillstore/marketplace.
- SKILL.md
- references/tdd-philosophy.md
- references/testing-anti-patterns.md
- skill-report.json
Open the folder on GitHubat commit ad8daf7
Compare with similar skills
Test Driven Development 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 Driven Development this skillaiskillstore/marketplace | 430 | — | ~1.9k | Automated safety check: Pass | None | |
| Test Guidelinesgetsentry/sentry-dart | 873 | — | ~3.1k | Automated safety check: Pass | MIT | |
| Characterisation Testscitypaul/.dotfiles | 739 | — | ~3.6k | Automated safety check: Pass | Custom licence | |
| TDD Refactor Guardgustavscirulis/snapgrid | 117 | 1 repos | ~1.8k | Automated safety check: Notes | Custom licence | |
| Test Guidelinesgetsentry/sentry-react-native | 1.8k | — | ~1.3k | Automated safety check: Pass | MIT | |
| Test Coveragescott-fryxell/brayness | 124 | — | ~1.6k | Automated safety check: Pass | MIT |
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Related
Categories
Questions about Test Driven Development
What does Test Driven Development do?
Red-green-refactor development methodology requiring verified test coverage. Test Driven Development is an agent skill from aiskillstore/marketplace. Red-green-refactor development methodology requiring verified test coverage.
When should I use Test Driven Development?
Test Driven Development fits situations like: feature implementation; any behavior changes where tests must prove correctness.
How do I install Test Driven Development in Claude Code?
Run `npx skills add aiskillstore/marketplace --skill test-driven-development -a claude-code`. Or copy the skill folder (skills/codingcossack/test-driven-development in aiskillstore/marketplace) into .claude/skills/test-driven-development in your project. Claude Code loads it when a task matches its description.
How do I install Test Driven Development in Codex?
Run `npx skills add aiskillstore/marketplace --skill test-driven-development -a codex`. Or copy the skill folder (skills/codingcossack/test-driven-development in aiskillstore/marketplace) into .agents/skills/test-driven-development in your project. Codex loads it when a task matches its description.
Can I use Test Driven Development 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 aiskillstore/marketplace --skill test-driven-development -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-driven-development, .gemini/skills/test-driven-development, .github/skills/test-driven-development and .opencode/skills/test-driven-development in your project.
What does Test Driven Development need to run?
Going by SKILL.md and its folder, Test Driven Development needs the command-line tools its instructions call (npm).
Does Test Driven Development access the network?
SKILL.md contains no URLs. Its commands use npm, which can reach the network depending on how they are called. This is read from the text; nothing was executed.
Is Test Driven Development safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Test Driven Development use?
No licence was found for Test Driven Development or its repository. Without one, default copyright applies: ask the author before reusing or redistributing it.
How many tokens does Test Driven Development use?
About 1.9k tokens (SKILL.md is roughly 7.5k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 2.8k tokens, read only when the agent opens those files.
What are the alternatives to Test Driven Development?
Skills that share tags, products or a category with Test Driven Development: Test Guidelines (getsentry/sentry-dart, 873 stars), Characterisation Tests (citypaul/.dotfiles, 739 stars), TDD Refactor Guard (gustavscirulis/snapgrid, 117 stars) and Test Guidelines (getsentry/sentry-react-native, 1.8k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Test Driven Development?
aiskillstore (a GitHub organization) maintains it in aiskillstore/marketplace, which has 430 GitHub stars. The repository holds 1,108 skills in this directory. The repository was last updated on October 7, 2026.
Source: aiskillstore/marketplace on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.