Borrowing it
Nothing to install: this file belongs to mahoushoujyo-eee/eshell. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/mahoushoujyo-eee/eshell/master/.codex/skills/test-driven-development/SKILL.mdgit clone --depth 1 https://github.com/mahoushoujyo-eee/eshellWrote 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.
[](https://agentmods.dev/skills/mahoushoujyo-eee/eshell/test-driven-development)<a href="https://agentmods.dev/skills/mahoushoujyo-eee/eshell/test-driven-development"><img src="https://agentmods.dev/badge/skills/mahoushoujyo-eee/eshell/test-driven-development/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.
<a href="https://agentmods.dev/skills/mahoushoujyo-eee/eshell/test-driven-development"><img src="https://agentmods.dev/badge/skills/mahoushoujyo-eee/eshell/test-driven-development.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00017 | $0.02406 |
| Opus 5.5 | $0.00007 | $0.00962 |
| Sonnet 5.5 | $0.00003 | $0.00481 |
| Haiku 4.5 | $0.00002 | $0.00241 |
Grade A, and why
test-driven-development 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 2mo 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.
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.
What ships with it
1 file 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.
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.
- 2mo ago First seen · 372 lines · 17 tokens per session scan A 7dee67b4af6b
test-driven-development is a skill published in the GitHub repository mahoushoujyo-eee/eshell (16 stars, last pushed 9d ago), with no licence file. It adds 17 tokens to every session and 2,406 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-09-01.
test-driven-development compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| test-driven-developmentmahoushoujyo-eee/eshell | Skill | 16 | 9d ago | none | A | 17 | Codex |
| engram-testing-coverageGentleman-Programming/engram | Skill | 7.8k | yesterday | MIT | A | 25 | Claude Code, Codex |
| principle-test-behavior-not-implementationmichael-denyer/pstack-claude | Skill | 4.1k | yesterday | MIT | A | 50 | Claude Code |
| tddcodewithmukesh/dotnet-claude-kit | Skill | 805 | 2d ago | MIT | A | 81 | Claude Code |
| nw-ddd-eventsourcingnWave-ai/nWave | Skill | 631 | yesterday | MIT | A | 38 | Claude Code |
| nw-fp-clojurenWave-ai/nWave | Skill | 631 | yesterday | MIT | A | 25 | Claude Code |
| nw-leanux-methodologynWave-ai/nWave | Skill | 631 | yesterday | MIT | A | 37 | Claude Code |