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/is-bo/fullstack-forge-skill/e2e-testing-patternsnpx skills add is-bo/fullstack-forge-skill --skill e2e-testing-patternsgit clone --depth 1 https://github.com/is-bo/fullstack-forge-skillWrote 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/is-bo/fullstack-forge-skill/e2e-testing-patterns)<a href="https://agentmods.dev/skills/is-bo/fullstack-forge-skill/e2e-testing-patterns"><img src="https://agentmods.dev/badge/skills/is-bo/fullstack-forge-skill/e2e-testing-patterns.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 | $0.00051 | $0.00941 |
| Opus 5 | $0.00026 | $0.00470 |
| Sonnet 5 | $0.00010 | $0.00188 |
| Haiku 4.5 | $0.00005 | $0.00094 |
Grade A, and why
e2e-testing-patterns 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 yesterday.
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.
This is a copy
100% identical to e2e-testing-patterns — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 128 lines — stays where its author put it; the contents beside it link to each section on GitHub.
E2E Testing Patterns
Build reliable, fast, and maintainable end-to-end test suites that provide confidence to ship code quickly and catch regressions before users do.
When to Use This Skill
- Implementing end-to-end test automation
- Debugging flaky or unreliable tests
- Testing critical user workflows
- Setting up CI/CD test pipelines
- Testing across multiple browsers
- Validating accessibility requirements
- Testing responsive designs
- Establishing E2E testing standards
Core Concepts
1. E2E Testing Fundamentals
What to Test with E2E:
- Critical user journeys (login, checkout, signup)
- Complex interactions (drag-and-drop, multi-step forms)
- Cross-browser compatibility
- Real API integration
- Authentication flows
What NOT to Test with E2E:
- Unit-level logic (use unit tests)
- API contracts (use integration tests)
- Edge cases (too slow)
- Internal implementation details
2. Test Philosophy
The Testing Pyramid:
/\
/E2E\ ← Few, focused on critical paths
/─────\
/Integr\ ← More, test component interactions
/────────\
/Unit Tests\ ← Many, fast, isolated
/────────────\
Best Practices:
- Test user behavior, not implementation
- Keep tests independent
- Make tests deterministic
- Optimize for speed
- Use data-testid, not CSS selectors
Detailed patterns and worked examples
Detailed pattern documentation lives in references/details.md. Read that file when the navigation tier above is insufficient.
Best Practices
- Use Data Attributes:
data-testidordata-cyfor stable selectors - Avoid Brittle Selectors: Don't rely on CSS classes or DOM structure
- Test User Behavior: Click, type, see - not implementation details
- Keep Tests Independent: Each test should run in isolation
- Clean Up Test Data: Create and destroy test data in each test
- Use Page Objects: Encapsulate page logic
- Meaningful Assertions: Check actual user-visible behavior
- Optimize for Speed: Mock when possible, parallel execution
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.
- yesterday First seen · 128 lines · 51 tokens per session scan A 1653690dde9e
e2e-testing-patterns is a skill published in the GitHub repository is-bo/fullstack-forge-skill (2 stars, last pushed 6d ago), licensed Apache-2.0. It adds 51 tokens to every session and 941 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to e2e-testing-patterns, differing in 0 lines, and is treated as a copy.
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