A multi-agent test-driven development workflow that separates test writing from implementation and follows the red-green-refactor cycle.

Use it to add features or fix bugs by first creating a failing test, then implementing the change and running feedback loops.

It keeps tests focused on the requirements instead of the implementation and provides checkpoints while work progresses.

tdd — Skill for Claude Code by glebis

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add glebis/claude-skills --skill tdd

Clone the repo

git clone --depth 1 https://github.com/glebis/claude-skills

Made for: Claude Code.

Or install tdd, the plugin that ships this one along with the rest of its 1 skill.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/glebis/claude-skills/tdd/github.svg)](https://agentmods.dev/skills/glebis/claude-skills/tdd)

Your own site

<a href="https://agentmods.dev/skills/glebis/claude-skills/tdd"><img src="https://agentmods.dev/badge/skills/glebis/claude-skills/tdd/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/glebis/claude-skills/tdd"><img src="https://agentmods.dev/badge/skills/glebis/claude-skills/tdd.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 92 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 8,238 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits

NVIDIA SkillSpector warn 7 Sept 2026

SkillSpector: 7 findings, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

medium Rogue Agent · line 228
Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.

Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
medium Rogue Agent · line 454
Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.

Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
medium MCP Rug Pull · line 601
npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.

Fix: Pin the version: npx @scope/[email protected]
medium MCP Rug Pull · line 601
npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.

Fix: Pin the version: npx @scope/[email protected]
medium Excessive Agency · line 689
Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.

Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
medium MCP Rug Pull · line 738
npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.

Fix: Pin the version: npx @scope/[email protected]
medium MCP Rug Pull · line 739
npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.

Fix: Pin the version: npx @scope/[email protected]

How audits are shown

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00092	$0.08238
Opus 5	$0.00046	$0.04119
Sonnet 5	$0.00018	$0.01648
Haiku 4.5	$0.00009	$0.00824

Measured 6d ago against content hash 8ff431a11ab2, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

tdd scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.

The scan reads SKILL.md. This mod also ships 11 executable files (scripts/discover_docs.sh, scripts/extract_api.sh, scripts/run_tests.sh, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

tdd/SKILL.md · 745 lines

How it starts

The opening of the file, as written. The whole thing — 745 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Test-Driven Development — Multi-Agent Orchestration

Enforce disciplined RED-GREEN-REFACTOR cycles using separate subagents for test writing and implementation. The core innovation: the Test Writer never sees implementation code, and the Implementer never sees the specification. This prevents the LLM from leaking implementation intent into test design.

When to Use

User requests TDD, test-first, or red-green-refactor workflow
User says /tdd with a feature description or bug report
User wants to add a feature with test coverage enforced from the start
User wants to fix a bug by first writing a reproducing test

Invocation Modes

Invocation	Behavior
`/tdd <feature>`	Interactive mode — pause for approval at slices and each RED checkpoint
`/tdd --auto <feature>`	Autonomous mode — run all slices without pausing; stop ONLY on unrecoverable errors
`/tdd --resume`	Resume from `.tdd-state.json` in project root
`/tdd --dry-run <feature>`	Validation mode — runs Phase 0 + Phase 1 fully, renders all prompts, but skips `Task()` calls. No code is written.

In --auto mode, skip all [HUMAN CHECKPOINT] steps. Print status lines instead:

[auto] RED  slice 1/4: "validates email format" — test failing as expected
[auto] GREEN slice 1/4: passing (attempt 1)
[auto] REFACTOR slice 1/4: 1 suggestion applied, 0 skipped

Stop and ask the user ONLY when:

Implementation fails after 5 attempts
Regressions cannot be auto-fixed after 3 attempts
A script error makes it impossible to continue (missing binary, permission denied, etc.)

In --dry-run mode, validate the entire orchestration pipeline without executing any subagents or writing any code:

Phase 0 runs fully: detect framework, verify baseline, extract API, discover docs, create state file
Phase 1 runs fully: decompose into slices (still requires user approval)
For each slice: render all three agent prompts (Test Writer, Implementer, Refactorer) with actual variables. Print rendered prompts to the user with character counts.
No Task() calls are made. No test files are written. No implementation code is generated.
Validate: check that all template variables resolve (no {UNRESOLVED} placeholders), all scripts execute without error, and the state file is well-formed.
Report summary:

Read the full file on GitHub · 745 lines

Files

What ships with it

25 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

6d ago First seen · 745 lines · 92 tokens per session scan A 8ff431a11ab2

Subscribe to this mod's changes

tdd is a skill published in the GitHub repository glebis/claude-skills (374 stars, last pushed 7d ago), licensed MIT. It adds 92 tokens to every session and 8,238 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

TDD Testing

tdd

Getting it into your agent

Wrote this? Show the measurements

What it costs to keep this loaded

Grade A, and why

Nothing flagged

How it starts

Test-Driven Development — Multi-Agent Orchestration

When to Use

Invocation Modes

What ships with it

What this file has done since we first saw it

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