tdd

tdd is a skill for Claude Code, Codex from j-jayes/agents-md. It costs 57 tokens per session (596 once invoked), scanned A, original, no licence file.

A test-driven development method in which you write a test, see it fail, and then change the code until it passes. TDD means test-driven development.

In plain words
What is it for?
Use it when adding features, fixing bugs, writing tests first, or when the user specifically asks for red/green TDD.
Why use it?
It makes the expected behaviour explicit before implementation and helps confirm that a bug fix or new feature works.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/j-jayes/agents-md/tdd
Any agent
npx skills add j-jayes/agents-md --skill tdd
Clone the repo
git clone --depth 1 https://github.com/j-jayes/agents-md

Made for: Claude Code, Codex.

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.

agentmods badge for tdd

README.md
[![agentmods](https://agentmods.dev/badge/skills/j-jayes/agents-md/tdd.svg)](https://agentmods.dev/skills/j-jayes/agents-md/tdd)
Your own site
<a href="https://agentmods.dev/skills/j-jayes/agents-md/tdd"><img src="https://agentmods.dev/badge/skills/j-jayes/agents-md/tdd.svg" alt="Measured on agentmods" height="20"></a>
Per session 57 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 596 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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.

ModelPer sessionOnce invoked
Fable 5 $0.00057 $0.00596
Opus 5 $0.00028 $0.00298
Sonnet 5 $0.00011 $0.00119
Haiku 4.5 $0.00006 $0.00060

Measured 3d ago against content hash e92250ba99ee, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 3d ago.

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.

.agents/skills/tdd/SKILL.md · 59 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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.

  1. 3d ago First seen · 59 lines · 57 tokens per session scan A e92250ba99ee

Subscribe to this mod's changes

tdd is a skill published in the GitHub repository j-jayes/agents-md (2 stars, last pushed 28d ago), with no licence file. It adds 57 tokens to every session and 596 once invoked, about $0.0003 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 2026-08-31.

Related

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