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 Ozzeron/prompt-pack --skill test-writergit clone --depth 1 https://github.com/Ozzeron/prompt-packWrote 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/ozzeron/prompt-pack/test-writer)<a href="https://agentmods.dev/skills/ozzeron/prompt-pack/test-writer"><img src="https://agentmods.dev/badge/skills/ozzeron/prompt-pack/test-writer/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/ozzeron/prompt-pack/test-writer"><img src="https://agentmods.dev/badge/skills/ozzeron/prompt-pack/test-writer.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 | $0.00095 | $0.02435 |
| Opus 5 | $0.00048 | $0.01218 |
| Sonnet 5 | $0.00019 | $0.00487 |
| Haiku 4.5 | $0.00010 | $0.00244 |
Grade A, and why
test-writer 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 2d 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.
How it starts
The opening of the file, as written. The whole thing — 241 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test Writer
You write tests for existing code. Tests document behaviour and catch regressions; they are not a coverage-percentage box to tick. You test what the code is supposed to do, not how it's currently structured. Implementation-coupled tests rot the moment refactors happen and become a tax on every change.
When to use
- Adding tests to existing untested code
- Filling a coverage gap on a specific function / component / endpoint
- Writing tests that should have caught a bug just fixed (regression tests)
- Pre-launch test pass for a feature
Do not invoke for:
- Writing code with tests included — that's part of
architecture/frontend-feature,architecture/backend-api, or whichever skill is doing the work - E2E test infrastructure setup — flag as separate work
- Snapshot-only changes (regenerating snapshots without thinking is not testing)
Scope
In scope:
- Unit tests for pure logic (functions, hooks, utilities, components)
- Integration tests at module / API / data-layer boundary
- Regression tests for fixed bugs
- Test fixtures and factories
- Mocking at the right boundary
Out of scope:
- E2E / browser / Playwright / Cypress test infrastructure (delegate or flag)
- Performance / load / chaos tests
- Test framework selection — match what the project uses
Inherits
meta/engineering-principles— naming, file size, single responsibility apply to tests too.meta/reuse-before-create— before writing a new fixture, factory, mock, or test helper, search for an existing one in the test tree; tests duplicate setup more than any other code.meta/token-discipline— read the unit under test and 1–2 sibling tests for style; not the whole test suite.
Token discipline (specific)
- Read the unit under test and its direct dependencies. Don't recursively read the whole module graph.
- Read 1–2 existing tests in the same project to learn conventions:
- Test file location (colocated vs
__tests__/vs mirrored structure) - Naming style (
describe('X')vstest('does Y')) - Setup / teardown patterns
- Fixture / factory helpers in use
- Test file location (colocated vs
- Read the test framework config (
vitest.config.*,jest.config.*,pytest.ini, etc.) once, only if needed. - Do NOT read tests of unrelated features.
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.
- 2d ago Changed · +2 lines · +69 tokens per session 8fa5c67ac9ef
- 9d ago First seen · 239 lines · 26 tokens per session scan A c0b2727e1ac6
test-writer is a skill published in the GitHub repository Ozzeron/prompt-pack (8 stars, last pushed 3d ago), licensed MIT. It adds 95 tokens to every session and 2,435 once invoked, about $0.0005 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.
Other skills, from other repositories
go-testing
Trigger: Go tests, go test coverage, Bubbletea teatest, golden files. Apply focused Go testing patterns.
dev-testing
A testing guide that defines when to use unit, integration, API, and end-to-end tests. Unit tests check small pieces of code, while end-to-end tests check a full user flow.
gentle-ai-bench
Trigger: bench, journey, journeys, driven mode, gentle-ai-bench, journey corpus, j-numbers, bench axis. Author and verify gentle-ai bench journeys; go test ./bench never proves driven execution.
memstack-development-test-writer
Use this skill when the user says 'write tests', 'add tests', 'test coverage', 'unit tests', 'integration tests', 'component tests', 'mocking', 'edge cases', or needs to generate tests with proper mocking and edge case coverage. Do NOT use for refactoring plans or database migrations.
typescript
TypeScript strict mode with eslint and jest.
ijfw-verify
Use when about to claim completion: 'done', 'fix complete', 'tests pass', 'build succeeded', 'shipped', 'no regressions', 'ready to merge', 'ready to ship'. Iron Law gate requiring fresh verification evidence in the same message as the claim; wires into runtime (verification-gate.js + the ijfwstate MCP tool…