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 skills add thiientv/godmode --skill test-driven-developmentgit clone --depth 1 https://github.com/thiientv/godmodeWrote 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/thiientv/godmode/test-driven-development)<a href="https://agentmods.dev/skills/thiientv/godmode/test-driven-development"><img src="https://agentmods.dev/badge/skills/thiientv/godmode/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/thiientv/godmode/test-driven-development"><img src="https://agentmods.dev/badge/skills/thiientv/godmode/test-driven-development.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00075 | $0.00463 |
| Opus 5.5 | $0.00030 | $0.00185 |
| Sonnet 5.5 | $0.00015 | $0.00093 |
| Haiku 4.5 | $0.00007 | $0.00046 |
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 1mo 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
Test-Driven Development
The test is an executable statement of behavior, not a coverage decoration.
Red-green-refactor
- Red: name one behavior and write the smallest test at the highest seam that can fail for the missing behavior.
- Verify red: run the focused command. Confirm it fails because the behavior is absent, not because of a typo, broken fixture, or setup error.
- Green: implement the simplest production change that makes the test pass. Do not add speculative options or unrelated cleanup.
- Verify green: run the focused test and relevant existing tests.
- Refactor: improve names, duplication, and boundaries while keeping the suite green. Add the next behavior only after the current loop is stable.
Honest tests
- Assert user-visible or contract-visible behavior, not private call counts.
- Prefer real collaborators; mock only an expensive, nondeterministic, or unavailable boundary and state why.
- Make failures diagnostic: clear name, small fixture, one cause.
- Include error, empty, boundary, retry, ordering, and permission cases when they are part of the contract.
Exceptions
For a prototype, generated output, or docs-only change, state why test-first is not useful and choose another observable check. “I will test later” is not an exception for production behavior.
Use test-design.md when the test seam or fixture
quality is unclear. Pair with root-cause-debugging for an existing failure
and completion-verification at the final gate.
Completion condition
The loop is credible when the test was observed failing for the intended reason, passes after the change, neighboring checks remain green, and the remaining untested behavior is named.
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.
- 1mo ago First seen · 51 lines · 75 tokens per session scan A 7113614524d5
test-driven-development is a skill published in the GitHub repository thiientv/godmode (99 stars, last pushed 2mo ago), licensed MIT. It adds 75 tokens to every session and 463 once invoked, about $0.0003 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 2026-08-30.
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