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.
npx agentmods add skills/a5c-ai/babysitter/test-driven-developmentnpx skills add a5c-ai/babysitter --skill test-driven-developmentgit clone --depth 1 https://github.com/a5c-ai/babysitterWrote 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/a5c-ai/babysitter/test-driven-development)<a href="https://agentmods.dev/skills/a5c-ai/babysitter/test-driven-development"><img src="https://agentmods.dev/badge/skills/a5c-ai/babysitter/test-driven-development.svg" alt="Measured on agentmods" 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 | $0.00035 | $0.00359 |
| Opus 5 | $0.00017 | $0.00179 |
| Sonnet 5 | $0.00007 | $0.00072 |
| Haiku 4.5 | $0.00003 | $0.00036 |
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 4d 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.
What it actually says
Non-Negotiable Rules
- Always use run mode (
CI=true npm testor--runflag) - NEVER use watch mode (prevents hanging processes)
- Use timeout guards (
timeout 60s) as backup - Record exit codes as evidence at each phase
- If tests fail 3 consecutive times in GREEN, report failure status
- Never skip RED phase (failing test must exist before implementation)
- Never defer tests to "later" -- TDD means tests first
Scope Discipline
- If implementation requires >3 file changes, flag for scope review
- Architectural choices require user approval unless pre-approved in plan
- New dependencies require user approval
When to Use
- Every feature implementation in BUILD workflow
- Every bug fix in DEBUG workflow (regression test)
Agents Used
component-builder(primary consumer)bug-investigator(regression tests)
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.
- 4d ago First seen · 41 lines · 35 tokens per session scan A 95a11c9ea167
test-driven-development is a skill published in the GitHub repository a5c-ai/babysitter (1,765 stars, last pushed today), licensed MIT. It adds 35 tokens to every session and 359 once invoked, about $0.0002 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 2026-08-30.
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