testing-strategy

A structured plan for deciding what software tests to write and where to run them. It covers unit tests for small pieces, integration tests for connected parts, and end-to-end tests for complete user flows.

In plain words
What is it for?
Use it to plan tests for APIs, data pipelines, frontends, or infrastructure. It produces areas to test, suitable test types, coverage targets, example cases, and missing-coverage notes.
Why use it?
It helps you balance test coverage with test speed and maintenance effort, while focusing on important behavior, errors, edge cases, security, and data accuracy.

Skill for Claude CodeCodex

Install

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.

agentmods
npx agentmods add skills/anthropics/knowledge-work-plugins/testing-strategy
Any agent
npx skills add anthropics/knowledge-work-plugins --skill testing-strategy
Clone the repo
git clone --depth 1 https://github.com/anthropics/knowledge-work-plugins

Made for: Claude Code, Codex.

Per session 56 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 273 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00056 $0.00273
Opus 5 $0.00028 $0.00137
Sonnet 5 $0.00011 $0.00055
Haiku 4.5 $0.00006 $0.00027

Measured 2d ago against content hash 5c5e95830754, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

testing-strategy 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.

Origin

Copies of this mod

3 near-identical copies found in the catalogue:

engineering/skills/testing-strategy/SKILL.md · 34 lines

What it actually says

Testing Strategy

Design effective testing strategies balancing coverage, speed, and maintenance.

Testing Pyramid

        /  E2E  \         Few, slow, high confidence
       / Integration \     Some, medium speed
      /    Unit Tests  \   Many, fast, focused

Strategy by Component Type

  • API endpoints: Unit tests for business logic, integration tests for HTTP layer, contract tests for consumers
  • Data pipelines: Input validation, transformation correctness, idempotency tests
  • Frontend: Component tests, interaction tests, visual regression, accessibility
  • Infrastructure: Smoke tests, chaos engineering, load tests

What to Cover

Focus on: business-critical paths, error handling, edge cases, security boundaries, data integrity.

Skip: trivial getters/setters, framework code, one-off scripts.

Output

Produce a test plan with: what to test, test type for each area, coverage targets, and example test cases. Identify gaps in existing coverage.

Changes

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.

  1. 2d ago First seen · 34 lines · 56 tokens per session scan A 5c5e95830754

Subscribe to this mod's changes

testing-strategy is a skill published in the GitHub repository anthropics/knowledge-work-plugins (23,791 stars, last pushed today), licensed Apache-2.0. It adds 56 tokens to every session and 273 once invoked, about $0.0003 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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