Imported from tester-army/e2e (
skills/e2e/SKILL.md) via skills.sh. Install upstream withnpx skills add tester-army/e2e --skill e2e. Copyright stays with the author.
e2e: agentic end-to-end tests in TypeScript
e2e runs UI tests with agent goals and exact assertions. agent.act drives
one goal; agent.assert, agent.waitFor, and agent.extract judge the
screen. screen, app, browser, and expect make exact interactions and
checks. The replay cache reruns verified actions and checks their recorded end
state without a model call; agent judgments still run live. UI targets use
@e2e-dev/web for browsers or @e2e-dev/mobile for iOS simulators,
Android emulators, and connected phones. A test that takes only app can check an API with fetch
and expect (topic writing-tests). Model sign-in commands are in
setup.
// e2e.config.ts
import type { E2EConfig } from 'e2e';
import { web } from '@e2e-dev/web';
import { gateway } from 'ai';
export default {
targets: [
{
engine: web(),
app: {
url: 'http://127.0.0.1:3000',
command: { executable: 'pnpm', args: ['dev'], log: '.e2e/logs/app.log' },
},
},
],
// The model behind every agent.* step: an AI SDK instance; gateway() from 'ai' reads AI_GATEWAY_API_KEY or a Vercel OIDC token.
agents: {
default: {
model: gateway('openai/gpt-6-luna-fast'),
system: 'You are a thorough QA agent. Verify every outcome on screen.',
},
},
} satisfies E2EConfig;
// tests/billing.e2e.ts
import { test } from '@e2e-dev/web';
import { expect } from 'e2e';
test('a member upgrades to Pro', async ({ app, agent, screen, browser }) => {
await app.open('/settings/billing');
await agent.act('upgrade the workspace to the Pro plan');
await expect(screen.getByRole('status')).toContainText('Pro');
await expect(browser).toHaveURL('/settings/billing');
});
Topics
Read the topic for the job before writing code. The files sit next to this
one; the installed CLI prints the same text with npx e2e guide <topic>
(e2e guide alone prints this page). For anything the topics do not cover,
the full documentation ships in the docs/ directory of the installed e2e
package (node_modules/e2e/docs in a single-package project); a link such as
/reference/cli is docs/reference/cli.mdx. Complete projects for Vite,
Next.js, Expo, and SwiftUI, each with its config, scripts, and a passing
suite, are in https://github.com/tester-army/e2e/tree/main/examples.
| Topic | File | Read it when |
|---|---|---|
setup |
references/setup.md | Adding e2e to a project, writing e2e.config.ts, starting the app from the config, mobile targets |
writing-tests |
references/writing-tests.md | Writing or fixing tests: fixtures, locators, actions, matchers, sign-in sessions, the browser fixture |
agent |
references/agent.md | Adding agent.* steps, picking a model, cost and budgets, the replay cache |
running |
references/running.md | CLI flags, reporters, .e2e/report.json, exit codes, CI |
explore |
references/explore.md | Exploring an app toward a goal without a test file: e2e explore, its budgets, verdict, and run.explore |
debugging |
references/debugging.md | A run failed: error codes and their fixes, --headed, --debug, --ai-trace |
mcp |
references/mcp.md | Driving the live app from a coding agent over MCP: e2e mcp, its tools, and the explore-then-write loop |
bug-bash |
references/bug-bash.md | Asked to bug bash, QA, or hunt for bugs across an app or a branch: parallel e2e explore charters, merging findings, proving each with a repro test |
Workflow
- Look at what exists:
e2e.config.tsore2e.config.mts, thetestsglob (defaulttests/**/*.e2e.ts),e2einpackage.json. Nothing there: followsetup. - Learn the screens before writing a test: routes, labels, roles, button
text. Semantic locators need the accessible names the app renders, so read
the components, open the page with
--headed, or drive the live app over the registerede2e mcpserver (topicmcp):open_session,observe, andlocateshow exact names and check a locator before you write it. - Write
tests/<feature>.e2e.ts. Drive the flow withagent.act, one goal per call, and pin each outcome right after withexpectoragent.assert. Exact values go throughscreen: a sign-in form in a setup test, a field that must receive one specific string, a count that must be one number. - Run one file:
npx e2e run tests/<feature>.e2e.ts. Agent steps need a model in the config and that provider's authentication (a saved subscription login, an API key); a local endpoint may need none. Tests without agent steps need no model. - Read the failure: the reporter prints the error code, message, and a code
frame;
.e2e/report.jsonhas every step and artifact path. Fix the locator, the expectation, or the app. Never add a sleep.
Rules
- Run the CLI as
npx e2e ...(orpnpm exec e2e ...). - The config is
export default { ... } satisfies E2EConfigwithimport type { E2EConfig } from 'e2e'.targetsis required; a UI target names an engine and declares the app beside it:{ engine: web(), app: { url, command } }. A tools-only target can omit the engine and setplatform. - Import
test,describe, the hooks,expect,credentials, andsecretsfrome2e. A test that uses thebrowserfixture importstest,describe, and the hooks from@e2e-dev/web: the same runtime functions, typed withbrowser. - Config and tests are ES modules whatever
package.jsonsets astype. - Locators resolve when used. Actions wait for readiness and
expectretries assertions. Reads such astextContent()fail at once on zero matches andcount()answers from the current screen; nothing waits for a value to change, so use a matcher when a value has to settle. - A locator that matches two nodes fails with
LOCATOR_AMBIGUOUS; narrow it (topicwriting-tests). - Secrets never appear in test code. Declare accounts under
credentialsand every other sensitive value undersecretsin the config; resolve withcredentials.user(name).passwordorsecrets.get(name)(separate namespaces:secrets.getnever returns a password), and hand the opaqueSecretonly tofill()oragent.actparams. - Agent instructions: one goal per
act, the wording on screen, real values in params. Judge meaning, not phrasing:toContain('Pro'), not an exact sentence a model produced. - Check each agent goal's outcome. A passing
actwith a recorded check can be cached and replayed without model calls (topicagent). - Shape the agent for this app:
contextfor vocabulary the screens use,systemfor how it works, tools for a test API, named personas underagents. When a step fails, tighten the goal first, then the context, then the agent. .e2e/is output (report.json,artifacts/,cache/,logs/; the config'soutputmoves the report and artifacts, nevercache/or the app's log). Read it, never edit it.
Feedback
When e2e itself gets in your way, tell the e2e team: a command or API that
broke (bug), docs or this skill that misled you (docs), or a capability
you needed and did not find (feature). Send it once per problem, after you
worked around it or gave up, never for failures of the app under test.
npx e2e feedback --type bug -m "<one or two sentences>" \
--task "<what you were doing>" --expected "<...>" --actual "<error code and message>" \
--approach "<what you tried>" --command "<e2e command>" --agent "<agent / model>"
Describe e2e's behavior only: never paste app content, page text, test files,
URLs of private apps, or credentials. Secret-named environment variables and
common token shapes are redacted, but do not rely on it. --dry-run prints
what would be sent. Tell the user you sent it and give them the reference id
it prints.
