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/narpatsinghpurohit/tstack/writing-testsnpx skills add narpatsinghpurohit/tstack --skill writing-testsgit clone --depth 1 https://github.com/narpatsinghpurohit/tstackWrote 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/narpatsinghpurohit/tstack/writing-tests)<a href="https://agentmods.dev/skills/narpatsinghpurohit/tstack/writing-tests"><img src="https://agentmods.dev/badge/skills/narpatsinghpurohit/tstack/writing-tests.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 5.1 | $0.00073 | $0.00438 |
| Opus 5 | $0.00036 | $0.00219 |
| Sonnet 5 | $0.00015 | $0.00088 |
| Haiku 4.5 | $0.00007 | $0.00044 |
Grade A, and why
writing-tests 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.
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
Task
Write tests for: $ARGUMENTS
Writing Tests
Determine test type
Backend (apps/api)?
- Unit test for service/controller → NestJS patterns
- E2E test for full HTTP flow → Supertest + mongodb-memory-server
Web (apps/web)?
- Component test → React Testing Library + MSW
- Hook test → renderHook + QueryClientProvider
- Store test → Direct Zustand state manipulation
Mobile (apps/mobile)?
- Screen test → Jest + React Native Testing Library + MSW
- Hook test → renderHook + QueryClientProvider + NavigationContainer
- Navigation test → NavigationContainer wrapper with initialParams
Conventions
- File naming:
<name>.spec.ts(backend),<name>.test.tsx(web and mobile) - One
describeblock per class/component - Nested
describeper method/behavior - Test names:
it('should <expected behavior>') - No test logic in loops — write explicit test cases
- Target 80%+ coverage
Examples
- examples/nestjs-test.md — NestJS unit test with mocked repos
- examples/react-test.md — React web component test with MSW
- examples/rn-test.md — React Native screen test with RNTL
References
- references/react-patterns.md — React web test patterns
- references/rn-patterns.md — React Native test patterns
What ships with it
5 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.
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 · 50 lines · 73 tokens per session scan A fc8db8815c6e
writing-tests is a skill published in the GitHub repository narpatsinghpurohit/tstack (5 stars, last pushed 5mo ago), licensed MIT. It adds 73 tokens to every session and 438 once invoked, about $0.0004 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.
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