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 kouroshez/coding-os --skill testing-strategygit clone --depth 1 https://github.com/kouroshez/coding-osWrote 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/kouroshez/coding-os/testing-strategy)<a href="https://agentmods.dev/skills/kouroshez/coding-os/testing-strategy"><img src="https://agentmods.dev/badge/skills/kouroshez/coding-os/testing-strategy/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/kouroshez/coding-os/testing-strategy"><img src="https://agentmods.dev/badge/skills/kouroshez/coding-os/testing-strategy.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 | $0.00118 | $0.03248 |
| Opus 5.5 | $0.00047 | $0.01299 |
| Sonnet 5.5 | $0.00024 | $0.00650 |
| Haiku 4.5 | $0.00012 | $0.00325 |
Grade A, and why
testing-strategy scanned grade A with 1 finding 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
End-to-end through a real browser (Playwright) / real mobile device (Detox / Maestro) / real API (curl-style integration). They are slow and flaky, so **keep them few and intentional**. How it starts
The opening of the file, as written. The whole thing — 267 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Testing Strategy — Pick the Right Layer
A practical playbook for designing test suites that catch real bugs without the suite itself becoming the bug. Stack-agnostic core; concrete recipes target this project's languages.
When to Use This Skill
- Adding the first test to a new module — the shape you ship now sets the suite's trajectory.
- Reviewing a PR where the test ratio looks off (e.g. all unit, no contract; all e2e, no unit).
- Investigating a flaky / slow suite — the cure is almost never "add retries".
- Deciding coverage targets for a service (90% lines is the wrong target).
- Adding tests to a bug fix — the fix without a regression test will return.
- Migrating from manual QA → automated CI.
Skip when: writing throwaway exploration code. Real code, real tests.
The Test Pyramid (still right, refined for 2026)
┌─────────┐
│ E2E │ ~5% slow, flake-prone, golden-path
┌───┴─────────┴───┐
│ Contract + │ ~15% pact, OpenAPI, GraphQL schema
│ Integration │
┌───┴─────────────────┴───┐
│ │
│ Unit + Property │ ~80% fast (ms), deterministic
│ │
└──────────────────────────┘
Targets are guidance, not law. A library has more unit + property than a deployment-heavy SaaS. A regulated app has more contract + integration than a hackathon prototype. What stays constant: most tests are fast; few tests are slow; zero tests are flaky.
The Six Layers — When Each Pays Off
| Layer | Speed | Catches | Use For |
|---|---|---|---|
| Unit | <10ms | Logic bugs, edge cases | Pure functions, calculators, parsers, mappers |
| Property-based | <100ms | Bugs you didn't think of | Invariants, parsers, encoders, ordering rules |
| Integration | <1s | Wiring bugs | DB queries (real DB, not mock), service composition |
| Contract | <100ms | Producer/consumer drift | API schemas, MCP envelope, event payloads |
| E2E | 5–60s | Full-stack regressions | One golden path per critical user flow |
| Smoke / run-the-deliverable | seconds | Import/entry crashes the unit suite hides (e.g. ModuleNotFoundError when run as a file) |
Every new runnable entrypoint — --help / --dry-run / python -c "import x", from the same entry the user or cron uses |
| Mutation / Fuzz | minutes (offline) | Tests that don't actually test | Quarterly audit, security-critical code |
What ships with it
3 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.
- 1mo ago First seen · 267 lines · 118 tokens per session scan A 2562eb43b596
testing-strategy is a skill published in the GitHub repository kouroshez/coding-os (7 stars, last pushed 7d ago), licensed Apache-2.0. It adds 118 tokens to every session and 3,248 once invoked, about $0.0005 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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