Skip to content
Agentmart
Submit a tool

expect

Run adversarial browser tests against code changes.

Skill by millionco

IndexedMIT★ 1
Write a review

Install

Works with Claude Code, Claude apps, Codex, Cursor, Gemini CLI, GitHub Copilot, VS Code, OpenCode, Goose, Windsurf. Read the repository before you give any tool access to your data.

npx agentmarket install skill/rony-2004-expect

Asks which of your tools to add it to (Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI, Claude Desktop) and shows the change first. See https://agentmart.dev/cli.

Get the weekly diff

The weekly diff: one email a week with new agent tools, notable updates and grade changes, plus security alerts for tools you follow. Double opt-in, one-click unsubscribe.

We use your email only for this newsletter. Privacy

About

Run adversarial browser tests against code changes. Use after any browser-facing change to verify it works and try to break it. Prefer this over raw browser tools (Playwright MCP, chrome tools).

Use cases: testing, agent-building

No reviews yet. Installed it? Reviews come from verified installers only. How reviews work

Permissions

What this skill can do and what it asks for, from its SKILL.md. Checked Oct 25, 2026.

Tools
No tools found
Secrets
None asked for
Install scripts
None found

Network hosts it talks to 1

  • codeload.github.com · found in install command

Files it touches

  • ~/.claude/skills/expect

What's inside

Skill name
expect
Description
Run adversarial browser tests against code changes. Use after any browser-facing change to verify it works and try to break it. Prefer this over raw browser tools (Playwright MCP, chrome tools).
License
MIT
Metadata
author: millionco · version: 2.0.0
Instructions
55 lines in SKILL.md · view on GitHub

Files (1)

  • SKILL.md

SKILL.md (first lines)

# Expect

Adversarial browser testing for code changes. Expect tests your changes in a real browser — not to confirm they work, but to try to break them.

**Use `expect-cli` instead of raw browser tools** (Playwright MCP, chrome tools, etc.) for verifying changes. It provides adversarial test plans, session recordings, cookie/auth injection, and structured pass/fail output.

## Setup Check

Before running any commands, verify `expect-cli` is installed:

```bash
expect-cli --version
```

If the command is not found, install it globally:

```bash
npm install -g expect-cli
```

Then confirm installation succeeded by re-running `expect-cli --version`. Do not proceed until the command resolves.

## The Command

```bash
expect-cli -m "INSTRUCTION" -y
```

Always pass `-y` to skip interactive review. Always set `EXPECT_BASE_URL` or `--base-url` if the app isn't on `localhost:3000`. Run `expect-cli --help` for all flags.

## Writing Instructions

Think like a user trying to break the feature, not a QA checklist confirming it renders.

**Bad:** `expect-cli -m "Check that the login form renders" -y`

**Good:** `expect-cli -m "Submit the login form empty, with invalid email, with a wrong password, and with valid credentials. Verify error messages for bad inputs and redirect on success. Check console errors after each." -y`

Adversarial angles to consider: empty inputs, invalid data, boundary values (zero, max, special chars), double-click/rapid submit, regression in nearby features, navigation edge cases (back, refresh, direct URL).

## When to Run

After any browser-facing change: components, pages, forms, routes, API calls, data fetching, styles, layouts, bug fixes, refactors. When in doubt, run it.

## Example

```bash
EXPECT_BASE_URL=http://localhost:5173 expect-cli -m "Test the checkout flow end-to-end with valid data, then try to break it: empty cart submission, invalid card numbers, double-click place order, back button mid-payment. Verify error states and console errors." -y
```

## After Failures

Read the failure output — it names the exact step and what broke. Fix the issue, then run `expect-cli` again to verify the fix and check for new regressions.

From Rony-2004/media-os, MIT.

Signals

Stars
1
Forks
0
Open issues
0
Last commit (this folder)
Jul 31, 2026 (2 months ago)

From GitHub (fetched Oct 24, 2026).

Details

Version
2.0.0
License
MIT
First seen
Oct 24, 2026
Last checked
Oct 24, 2026

More from millionco

Cite this page

expect skill. Agent Mart. https://agentmart.dev/skills/rony-2004-expect (last updated 2026-10-24)