ECC is a toolkit that organizes and improves how coding agents work through skills, memory, security checks, research practices, and related extensions. It is for developers using agents such as Claude Code, Codex, OpenCode, and Cursor.
Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/affaan-m/ECCnpx agentmods add skills/affaan-m/ecc/e2e-testingWrote 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/affaan-m/ecc/e2e-testing)<a href="https://agentmods.dev/skills/affaan-m/ecc/e2e-testing"><img src="https://agentmods.dev/badge/skills/affaan-m/ecc/e2e-testing/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/affaan-m/ecc/e2e-testing"><img src="https://agentmods.dev/badge/skills/affaan-m/ecc/e2e-testing.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector warn
SkillSpector: 4 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium MCP Rug Pull · line 157 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 158 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 240 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 241 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
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 | $0.00053 | $0.02119 |
| Opus 5.5 | $0.00021 | $0.00848 |
| Sonnet 5.5 | $0.00011 | $0.00424 |
| Haiku 4.5 | $0.00005 | $0.00212 |
Grade A, and why
e2e-testing 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 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.
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.
Copies of this mod
8 near-identical copies found in the catalogue:
- e2e-testing — 100% identical, 1 lines differ
- e2e-testing — 92% identical, 5 lines differ
- e2e-testing — 92% identical, 5 lines differ
- e2e-testing — 92% identical, 3 lines differ
- e2e-testing — 92% identical, 3 lines differ
- e2e-testing — 92% identical, 3 lines differ
- e2e-testing — 92% identical, 6 lines differ
- e2e-testing — 84% identical, 5 lines differ
How it starts
The opening of the file, as written. The whole thing — 327 lines — stays where its author put it; the contents beside it link to each section on GitHub.
E2E Testing Patterns
Comprehensive Playwright patterns for building stable, fast, and maintainable E2E test suites.
Test File Organization
tests/
├── e2e/
│ ├── auth/
│ │ ├── login.spec.ts
│ │ ├── logout.spec.ts
│ │ └── register.spec.ts
│ ├── features/
│ │ ├── browse.spec.ts
│ │ ├── search.spec.ts
│ │ └── create.spec.ts
│ └── api/
│ └── endpoints.spec.ts
├── fixtures/
│ ├── auth.ts
│ └── data.ts
└── playwright.config.ts
Page Object Model (POM)
import { Page, Locator } from '@playwright/test'
export class ItemsPage {
readonly page: Page
readonly searchInput: Locator
readonly itemCards: Locator
readonly createButton: Locator
constructor(page: Page) {
this.page = page
this.searchInput = page.locator('[data-testid="search-input"]')
this.itemCards = page.locator('[data-testid="item-card"]')
this.createButton = page.locator('[data-testid="create-btn"]')
}
async goto() {
await this.page.goto('/items')
await this.page.waitForLoadState('networkidle')
}
async search(query: string) {
await this.searchInput.fill(query)
await this.page.waitForResponse(resp => resp.url().includes('/api/search'))
await this.page.waitForLoadState('networkidle')
}
async getItemCount() {
return await this.itemCards.count()
}
}
Test Structure
import { test, expect } from '@playwright/test'
import { ItemsPage } from '../../pages/ItemsPage'
test.describe('Item Search', () => {
let itemsPage: ItemsPage
test.beforeEach(async ({ page }) => {
itemsPage = new ItemsPage(page)
await itemsPage.goto()
})
test('should search by keyword', async ({ page }) => {
await itemsPage.search('test')
const count = await itemsPage.getItemCount()
expect(count).toBeGreaterThan(0)
await expect(itemsPage.itemCards.first()).toContainText(/test/i)
await page.screenshot({ path: 'artifacts/search-results.png' })
})
test('should handle no results', async ({ page }) => {
await itemsPage.search('xyznonexistent123')
await expect(page.locator('[data-testid="no-results"]')).toBeVisible()
expect(await itemsPage.getItemCount()).toBe(0)
})
})
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.
- 1mo ago Changed · +1 lines 8cfa22c35e53
- 1mo ago First seen · 326 lines · 53 tokens per session scan A 5c2c7efc73e5
e2e-testing is a skill published in the GitHub repository affaan-m/ECC (283,276 stars, last pushed 3d ago), licensed MIT. It adds 53 tokens to every session and 2,119 once invoked, about $0.0002 per session on Opus 5.5. 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.
Other skills, from other repositories
dogfood
Exploratory QA of web apps: find bugs, evidence, reports.
playwright-cli
Automate browser interactions, test web pages and work with Playwright tests.
webapp-testing
Toolkit for interacting with and testing local web applications using Playwright. Supports verifying frontend functionality, debugging UI behavior, capturing browser screenshots, and viewing browser logs.
e2e-testing-patterns
Master end-to-end testing with Playwright and Cypress to build reliable test suites that catch bugs, improve confidence, and enable fast deployment. Use when implementing E2E tests, debugging flaky tests, or establishing testing standards.
playwright-cli
Automates browser interactions for web testing, form filling, screenshots, and data extraction. Use when the user needs to navigate websites, interact with web pages, fill forms, take screenshots, test web applications, or extract information from web pages.
langbot-testing
Test LangBot WebUI and core product flows with an automated browser and backend logs. Use when validating the configured LangBot frontend, pipeline Debug Chat, model provider setup and test buttons, bot and knowledge-base UI flows, or troubleshooting failed LangBot end-to-end tests.