Agent skill

TDD

Test-Driven Development workflow. An agent skill from 2SSK/dot-files.

MITAuto-check passedTesting & QA

Install TDD

skills CLI

$ npx skills add 2SSK/dot-files --skill tdd -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install 2SSK/dot-files tdd --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/2SSK/dot-files.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.claude/skills/tdd .claude/skills/tdd && rm -rf skills-src

Use ~/.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/

Paste into Claude Code

Install the "tdd" agent skill from https://github.com/2SSK/dot-files/tree/main/.claude/skills/tdd into .claude/skills/tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "tdd", 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

$skill-installer install https://github.com/2SSK/dot-files/tree/main/.claude/skills/tdd

Type 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.

skills CLI

$ npx skills add 2SSK/dot-files --skill tdd -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install 2SSK/dot-files tdd --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/2SSK/dot-files.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.claude/skills/tdd .agents/skills/tdd && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "tdd" agent skill from https://github.com/2SSK/dot-files/tree/main/.claude/skills/tdd into .agents/skills/tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "tdd", 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.

skills CLI

$ npx skills add 2SSK/dot-files --skill tdd -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install 2SSK/dot-files tdd --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/2SSK/dot-files.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.claude/skills/tdd .cursor/skills/tdd && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "tdd" agent skill from https://github.com/2SSK/dot-files/tree/main/.claude/skills/tdd into .cursor/skills/tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "tdd", 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

$ gemini skills install https://github.com/2SSK/dot-files.git --path .claude/skills/tdd

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add 2SSK/dot-files --skill tdd -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install 2SSK/dot-files tdd --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/2SSK/dot-files.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.claude/skills/tdd .gemini/skills/tdd && rm -rf skills-src

Use ~/.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/

Paste into Gemini CLI

Install the "tdd" agent skill from https://github.com/2SSK/dot-files/tree/main/.claude/skills/tdd into .gemini/skills/tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "tdd", 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.

GitHub CLI

$ gh skill install 2SSK/dot-files tdd

Installs 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).

skills CLI

$ npx skills add 2SSK/dot-files --skill tdd -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/2SSK/dot-files.git skills-src && mkdir -p .github/skills && cp -r skills-src/.claude/skills/tdd .github/skills/tdd && rm -rf skills-src

Use ~/.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/

Paste into GitHub Copilot

Install the "tdd" agent skill from https://github.com/2SSK/dot-files/tree/main/.claude/skills/tdd into .github/skills/tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "tdd", 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.

skills CLI

$ npx skills add 2SSK/dot-files --skill tdd -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install 2SSK/dot-files tdd --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/2SSK/dot-files.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.claude/skills/tdd .opencode/skills/tdd && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "tdd" agent skill from https://github.com/2SSK/dot-files/tree/main/.claude/skills/tdd into .opencode/skills/tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "tdd", 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: tdd
GitHub stars: 247
Token cost: ~444 tokens
SKILL.md length: 115 words
Files: 1
Skills in repo: 7
Repo updated: Sep 12, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

Test-Driven Development workflow. An agent skill from 2SSK/dot-files.

Works in 3 steps: Write Failing Test → Write Minimal Code → Refactor
Tasks that involve Test-driven development
SKILL.md covers Workflow, Testing Patterns by Language and Quality Gates
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

TDD is an agent skill from 2SSK/dot-files. Test-Driven Development workflow. Write failing test first, implement code to pass, then refactor. Essential for all languages: Go, TypeScript, C++, Python. Use before any implementation task.

Its SKILL.md is about 440 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts. Compatibility notes: opencode

It sits in Testing & QA, covering Test-driven development. It works with C++, TypeScript and Python. The licence is MIT.

When your agent uses it

Tasks that involve Test-driven development

Example prompts

“/tdd”

Requirements

Compatibility (from SKILL.md): opencode

Workflow steps

3 steps, taken from the step headings in SKILL.md.

Write Failing Test
Write Minimal Code
Refactor

What it can do on your machine

Read from SKILL.md and the folder at commit 5cab3b1. 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
No scripts in the folder and no shell commands in SKILL.md (its code samples are go, typescript and cpp).
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.
Compatibility
opencode
From compatibility in the SKILL.md frontmatter.

Context cost

TDD loads about 444 tokens when it runs. Until then it costs about 49 tokens; SKILL.md has 115 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~49
When it runs · the whole SKILL.md, loaded when a task matches: ~444

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

The full file from 2SSK/dot-files at commit 5cab3b1, republished under its MIT licence (© 2SSK). 115 words, ~444 tokens.

Download SKILL.mdSave it as .claude/skills/tdd/SKILL.md (or your agent's skills folder).

name: tdd
description: Test-Driven Development workflow. Write failing test first, implement code to pass, then refactor. Essential for all languages: Go, TypeScript, C++, Python. Use before any implementation task.
compatibility: opencode

Test-Driven Development Skill

Enforce TDD for every implementation task. This skill ensures quality throughtests first.

Workflow

Step 1 — Write Failing Test

Identify the smallest unit of behavior
Write test that fails because feature doesn't exist
Use language-specific testing framework
Keep test focused and simple

Step 2 — Write Minimal Code

Implement only what's needed to pass test
No optimization yet
No additional features
Get to green quickly

Step 3 — Refactor

Clean up code while tests pass
Improve structure, names, organization
Ensure tests still pass
No new functionality

Testing Patterns by Language

Go

func TestUnitName(t *testing.T) {
    t.Run("should do thing", func(t *testing.T) {
        // arrange
        input := ...
        expected := ...
        
        // act
        result := DoThing(input)
        
        // assert
        assert.Equal(t, expected, result)
    })
}

TypeScript

typescript

describe('UnitName', () => {
  it('should do thing', () => {
    const input = ...;
    const expected = ...;
    
    const result = doThing(input);
    
    expect(result).toEqual(expected);
  });
});

C++

cpp

TEST_F(UnitNameTest, ShouldDoThing) {
    auto input = ...;
    auto expected = ...;
    
    auto result = doThing(input);
    
    EXPECT_EQ(expected, result);
}

Quality Gates

All tests must pass before commit
Coverage ≥ 80% for new code
No flaky tests
Fast execution (< 30s for unit tests)

Files

Just SKILL.md in .claude/skills/tdd of 2SSK/dot-files.

Open the folder on GitHubat commit 5cab3b1

Compare with similar skills

TDD 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.

TDD compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
TDD this skill2SSK/dot-files	247	—	~444	Automated safety check: Pass	MIT	25 days ago
Growing Outside In Systemslexler/skill-factory	239	1 repos	~1.9k	Automated safety check: Pass	Apache-2.0	1 mo ago
Failure Oriented InstrumentationArabelaTso/Skills-4-SE	253	—	~2.1k	Automated safety check: Pass	Apache-2.0	1 mo ago
CodeQL Security Scantrailofbits/skills	7.4k	—	~4.6k	Automated safety check: Notes	CC-BY-SA-4.0	5 days ago
Dbgtheodo-group/debug-that	158	—	~1.9k	Automated safety check: Pass	MIT	4 mo ago
Tbdjlevy/strif	131	—	~3.5k	Automated safety check: Pass	MIT	4 mo ago

Similar skills

Growing Outside In Systems
lexler/skill-factory
Drive feature development using Outside-In TDD with Hexagonal Architecture.
239 GitHub starsUsed in 1 repo~1.9k tokens
Testing & QAAuto-check passed
Failure Oriented Instrumentation
ArabelaTso/Skills-4-SE
Selectively instruments code to capture runtime data for debugging failures and bugs.
253 GitHub stars~2.1k tokensUpdated 1 mo ago
DevelopmentAuto-check passed
CodeQL Security Scan
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Official
Scans a codebase for vulnerabilities with CodeQL's data flow and taint tracking in run-all or important-only modes, including data extensions for project-specific sources and sinks.
7.4k GitHub stars~4.6k tokensUpdated 5 days ago
SecurityAuto-check: notes
Dbg
theodo-group/debug-that
Debug applications using the dbg CLI debugger. An agent skill from theodo-group/debug-that.
158 GitHub stars~1.9k tokensUpdated 4 mo ago
DevelopmentAuto-check passed
Tbd
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Git-native issue tracking (beads), coding guidelines, knowledge injection, and spec-driven planning for AI agents.
131 GitHub stars~3.5k tokensUpdated 4 mo ago
DevelopmentAuto-check passed
Developing Software
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Questions about TDD

What does TDD do?

Test-Driven Development workflow. An agent skill from 2SSK/dot-files. TDD is an agent skill from 2SSK/dot-files. Test-Driven Development workflow.

When should I use TDD?

TDD fits situations like: tasks that involve Test-driven development.

How do I install TDD in Claude Code?

Run `npx skills add 2SSK/dot-files --skill tdd -a claude-code`. Or copy the skill folder (.claude/skills/tdd in 2SSK/dot-files) into .claude/skills/tdd in your project. Claude Code loads it when a task matches its description.

How do I install TDD in Codex?

Run `npx skills add 2SSK/dot-files --skill tdd -a codex`. Or copy the skill folder (.claude/skills/tdd in 2SSK/dot-files) into .agents/skills/tdd in your project. Codex loads it when a task matches its description.

Can I use TDD 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 2SSK/dot-files --skill tdd -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/tdd, .gemini/skills/tdd, .github/skills/tdd and .opencode/skills/tdd in your project.

What does TDD need to run?

SKILL.md names no scripts, command-line tools or credentials: TDD is instructions for the agent only. Compatibility (from SKILL.md): opencode.

Does TDD 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 TDD 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 TDD use?

TDD 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 TDD use?

About 444 tokens (SKILL.md is roughly 1.8k 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 TDD?

Skills that share tags, products or a category with TDD: Growing Outside In Systems (lexler/skill-factory, 239 stars), Failure Oriented Instrumentation (ArabelaTso/Skills-4-SE, 253 stars), CodeQL Security Scan (trailofbits/skills, 7.4k stars) and Dbg (theodo-group/debug-that, 158 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains TDD?

2SSK (a GitHub user) maintains it in 2SSK/dot-files, which has 247 GitHub stars. The repository holds 7 skills in this directory. The repository was last updated on September 12, 2026.

Source: 2SSK/dot-files on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Install TDD

Facts

At a glance

What it does

When your agent uses it

Example prompts

Requirements

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Compatibility

Context cost

Safety

SKILL.md

Test-Driven Development Skill

Workflow

Step 1 — Write Failing Test

Step 2 — Write Minimal Code

Step 3 — Refactor

Testing Patterns by Language

Go

TypeScript

C++

Quality Gates

Files

Compare with similar skills

Similar skills

More from 2SSK/dot-files

Related

Questions about TDD