Agent skill

Skill TDD

Build a behavior change with observed red, minimal green, and measured test consolidation

MITAuto-check passedTesting & QA

Install Skill TDD

skills CLI

$ npx skills add nyldn/claude-octopus --skill skill-tdd -a claude-code

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

GitHub CLI

$ gh skill install nyldn/claude-octopus skill-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/nyldn/claude-octopus.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/skill-tdd .claude/skills/skill-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 "skill-tdd" agent skill from https://github.com/nyldn/claude-octopus/tree/main/skills/skill-tdd into .claude/skills/skill-tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-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/nyldn/claude-octopus/tree/main/skills/skill-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 nyldn/claude-octopus --skill skill-tdd -a codex

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

GitHub CLI

$ gh skill install nyldn/claude-octopus skill-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/nyldn/claude-octopus.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/skill-tdd .agents/skills/skill-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 "skill-tdd" agent skill from https://github.com/nyldn/claude-octopus/tree/main/skills/skill-tdd into .agents/skills/skill-tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-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 nyldn/claude-octopus --skill skill-tdd -a cursor

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

GitHub CLI

$ gh skill install nyldn/claude-octopus skill-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/nyldn/claude-octopus.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/skill-tdd .cursor/skills/skill-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 "skill-tdd" agent skill from https://github.com/nyldn/claude-octopus/tree/main/skills/skill-tdd into .cursor/skills/skill-tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-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/nyldn/claude-octopus.git --path skills/skill-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 nyldn/claude-octopus --skill skill-tdd -a gemini-cli

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

GitHub CLI

$ gh skill install nyldn/claude-octopus skill-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/nyldn/claude-octopus.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/skill-tdd .gemini/skills/skill-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 "skill-tdd" agent skill from https://github.com/nyldn/claude-octopus/tree/main/skills/skill-tdd into .gemini/skills/skill-tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-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 nyldn/claude-octopus skill-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 nyldn/claude-octopus --skill 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/nyldn/claude-octopus.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/skill-tdd .github/skills/skill-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 "skill-tdd" agent skill from https://github.com/nyldn/claude-octopus/tree/main/skills/skill-tdd into .github/skills/skill-tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-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 nyldn/claude-octopus --skill 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 nyldn/claude-octopus skill-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/nyldn/claude-octopus.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/skill-tdd .opencode/skills/skill-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 "skill-tdd" agent skill from https://github.com/nyldn/claude-octopus/tree/main/skills/skill-tdd into .opencode/skills/skill-tdd/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "skill-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: skill-tdd
GitHub stars: 4.2k
Used in: 1 other repo
Token cost: ~805 tokens
SKILL.md length: 426 words
Files: 2
Skills in repo: 62
Repo updated: Oct 9, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

Build a behavior change with observed red, minimal green, and measured test consolidation

Works in 6 steps: Name the observable behavior and the… → Write one focused test. Directly test an… → Run it and record the expected failure,… → …
Tasks that involve Test-driven development
SKILL.md covers The rule, Consolidating tests and Strategy rotation
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Skill TDD is an agent skill from nyldn/claude-octopus. Build a behavior change with observed red, minimal green, and measured test consolidation

Its SKILL.md is about 810 tokens, which your agent loads only when the skill is triggered. The skill folder holds 2 other files (for example `agents/openai.yaml`).

It sits in Testing & QA, covering Test-driven development. The repository describes itself as: Run multiple AI models against the same research, design, or coding task. Surface disagreements before you ship. The licence is MIT.

When your agent uses it

Tasks that involve Test-driven development

Example prompts

“/skill-tdd”

Workflow steps

6 steps, taken from the first numbered list in SKILL.md.

Name the observable behavior and the smallest public boundary that proves it.
Write one focused test. Directly test an internal invariant only when the
Run it and record the expected failure, command, and exit status.
Implement the smallest change that passes.
Run the focused test, then the affected suite.
Refactor only while the tests remain green.

What it can do on your machine

Read from SKILL.md and the folder at commit e14b84f. 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.
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

Skill TDD loads about 805 tokens when it runs. Until then it costs about 25 tokens; SKILL.md has 426 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~25
When it runs · the whole SKILL.md, loaded when a task matches: ~805

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 nyldn/claude-octopus at commit e14b84f, republished under its MIT licence (© nyldn). 426 words, ~805 tokens.

Download SKILL.mdSave it as .claude/skills/skill-tdd/SKILL.md (or your agent's skills folder). This skill also uses 1 other file; get the full folder from GitHub.

name: skill-tdd
description: Build a behavior change with observed red, minimal green, and measured test consolidation
disable-model-invocation: true

Host: Codex CLI — This skill was designed for Claude Code and adapted for Codex. Cross-reference commands use installed skill names in Codex rather than /octo:* slash commands. Use the active Codex shell and subagent tools. Do not claim a provider, model, or host subagent is available until the current session exposes it. For host tool equivalents, see skills/blocks/codex-host-adapter.md.

Test-driven development

Read skills/blocks/engineering-method-selection.md from the installed plugin for review admission. Natural-language requests and --peer-review share that policy. Honor host-only requests; risk alone does not authorize paid usage.

Run the red, green, and refactor cycle on the current host. Routine TDD makes zero additional provider dispatches. Use one external reviewer only when the user passes --peer-review, explicitly requests independent review, or an existing risk policy requires it. Explicit debate, council, and multi-model commands retain their own execution contracts.

<HARD-GATE>
NO PRODUCTION BEHAVIOR CHANGE WITHOUT AN OBSERVED, EXPECTED FAILING TEST FIRST.
</HARD-GATE>

The rule

Do not change production behavior until a focused test fails for the expected reason. Existing implementation outside the requested change remains intact.

Name the observable behavior and the smallest public boundary that proves it.
Write one focused test. Directly test an internal invariant only when the public boundary cannot isolate its failure mode.
Run it and record the expected failure, command, and exit status.
Implement the smallest change that passes.
Run the focused test, then the affected suite.
Refactor only while the tests remain green.

If a test passes before implementation, it is not red evidence. If it errors due to fixture or syntax problems, repair the test until it fails on the missing behavior.

Show full SKILL.md (154 more words)Show less

Consolidating tests

Do not equate similar assertions with duplicate guarantees. Keep separate OS, security, cancellation, and integration boundaries. For every removed test, record old_test, behavior, replacement, mutant, red_observed, baseline_ms, candidate_ms, and reason. The retained test must kill the named mutant at the intended caller boundary.

After one warm-up, measure five isolated runs and report every sample and the median. Review a slowdown only when it exceeds both 20 percent and 100 ms.

Completion requires observed red and green evidence, affected-suite results, and the consolidation ledger when tests were removed. A missing reviewer is reported as incomplete review, never simulated.

Strategy rotation

If the same test remains red after two implementation attempts, stop and recheck the test boundary, fixture, and expected behavior. The strategy-rotation hook is a signal to try a fundamentally different hypothesis, not another variation of the same patch.

Adapted from DEEPENING in mattpocock/skills at commit 3cca18b368ae95cdbdebbff572ccafa662551015 under the MIT License. See THIRD_PARTY_NOTICES.md.

Files

SKILL.md and 1 other file in skills/skill-tdd of nyldn/claude-octopus.

SKILL.md
agents/openai.yaml

Open the folder on GitHubat commit e14b84f

Used in 1 other repository

We found 2 copies of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in nyldn/claude-octopus, which our catalogue first saw on October 7, 2026.

hashgraph-online/awesome-codex-pluginsplugins/nyldn/claude-octopus/skills/skill-tdd

Compare with similar skills

Skill 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.

Skill TDD compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Skill TDD this skillnyldn/claude-octopus	4.2k	1 repos	~805	Automated safety check: Pass	MIT	today
TDDpietheinstrengholt/rssmonster	564	30 repos	~906	Automated safety check: Pass	MIT	yesterday
TDD WorkflowhellangleZ/burn-in-cceverywhere-ralph	112	11 repos	~2.4k	Automated safety check: Pass	None	8 mo ago
TDDsanity-io/sanity	6.4k	20 repos	~1k	Automated safety check: Pass	MIT	today
Test Driven Developmentfarm-fe/farm	5.6k	51 repos	~2.5k	Automated safety check: Pass	MIT	17 days ago
Tapd Story PipelineTencentBlueKing/bk-bcs	841	—	~2.6k	Automated safety check: Pass	Custom licence	yesterday

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Questions about Skill TDD

What does Skill TDD do?

Build a behavior change with observed red, minimal green, and measured test consolidation. Skill TDD is an agent skill from nyldn/claude-octopus.

When should I use Skill TDD?

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

How do I install Skill TDD in Claude Code?

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

How do I install Skill TDD in Codex?

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

Can I use Skill 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 nyldn/claude-octopus --skill 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/skill-tdd, .gemini/skills/skill-tdd, .github/skills/skill-tdd and .opencode/skills/skill-tdd in your project.

What does Skill TDD need to run?

SKILL.md names no scripts, command-line tools or credentials: Skill TDD is instructions for the agent only.

Does Skill 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 Skill 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 Skill TDD use?

Skill 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 Skill TDD use?

About 805 tokens (SKILL.md is roughly 3.2k 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 Skill TDD?

Skills that share tags, products or a category with Skill TDD: TDD (pietheinstrengholt/rssmonster, 564 stars), TDD Workflow (hellangleZ/burn-in-cceverywhere-ralph, 112 stars), TDD (sanity-io/sanity, 6.4k stars) and Test Driven Development (farm-fe/farm, 5.6k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Skill TDD?

nyldn (a GitHub user) maintains it in nyldn/claude-octopus, which has 4,192 GitHub stars. The repository holds 62 skills in this directory. The repository was last updated on October 9, 2026.

Source: nyldn/claude-octopus on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Skill TDD

Install Skill TDD

Facts

At a glance

What it does

When your agent uses it

Example prompts

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Test-driven development

The rule

Consolidating tests

Strategy rotation

Files

Used in 1 other repository

Compare with similar skills

Similar skills

TDD

TDD Workflow

TDD

Test Driven Development

Tapd Story Pipeline

Absolute Init

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Skill Audit

Skill Content Pipeline

Skill Context Detection

Questions about Skill TDD

Install Skill TDD

Facts

At a glance

What it does

When your agent uses it

Example prompts

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Test-driven development

The rule

Consolidating tests

Strategy rotation

Files

Used in 1 other repository

Compare with similar skills

Similar skills

More from nyldn/claude-octopus

Related

Questions about Skill TDD