UI Test Agent
Plain-English browser QA inside GitHub Copilot Chat. Smoke, accessibility, performance, console, link, and responsive checks across desktop, tablet, and mobile — every run produces an evidence-backed Markdown report. No test code. No DSL. No configuration files.
What it does
Type what you want to verify, in English. The agent drives a real browser, performs the checks, and writes a report.
@UI Test Test https://example.com on desktop, mobile, tablet
/ui-test-smoke url=https://example.com
/ui-test-a11y url=https://example.com
/ui-test-perf url=https://example.com device=mobile
/ui-test-responsive url=https://example.com devices=mobile,mobileSm,tablet
/ui-test-scaffold
Install the extension, open Copilot Chat, and ask. The agent narrates its scope, runs the checks, and replies with a Markdown report. When you scaffold a project, it writes a committable ./.ui-tests/ folder with starter cases and a reports/ output directory.
Eight ready-to-use workflows
| Prompt |
What it verifies |
/ui-test-smoke |
Page load, title, no console errors, no 5xx responses |
/ui-test-console |
Runtime console + network health |
/ui-test-a11y |
Accessibility audit (WCAG / axe) with rule-by-rule findings |
/ui-test-perf |
Performance audit + Core Web Vitals (LCP, INP, CLS) |
/ui-test-links |
Same-origin link health and shallow crawl |
/ui-test-responsive |
Overflow, layout, and touch-target audit across breakpoints |
/ui-test-scaffold |
Bootstrap a starter .ui-tests/ suite for your project |
/ui-test-run |
Bulk-run a folder of *.ui-test.md cases |
Every workflow can fan out across the standard device matrix (desktop · desktopHD · tablet · tabletLand · mobile · mobileSm) with optional network and CPU throttling.
Why teams use it
- Plain English in, evidence out. Reports include screenshots, scores, console errors, and failed requests — everything you need to triage.
- Markdown-native test cases. Scaffolded suites are diff-friendly
.ui-test.md files. Commit them, review them in PRs, evolve them with your product.
- One-click install. No extension chains, no setup wizard, no config files to write.
- Read-only on your code. The agent can scaffold tests and write reports — but it cannot modify your application source. Ever.
- Six device profiles. Desktop, large desktop, tablet (portrait/landscape), mobile, and small mobile, all with realistic viewports and DPR.
Requirements
You need an active GitHub Copilot subscription (Individual, Business, or Enterprise) with Copilot Chat enabled. The agent runs on top of Copilot Chat in Agent Mode — without an active subscription the chat surface is unavailable and the agent cannot run. A Copilot Free trial works for evaluation.
You also need:
- VS Code 1.101+ with the GitHub Copilot Chat extension installed and signed in.
- Node.js 18+ on
PATH.
- Google Chrome / Chromium / Edge installed locally (auto-detected).
The extension probes your environment on first run and offers one-click actions to install anything that's missing.
Quick start
- Install this extension from the VS Code Marketplace.
- Make sure you're signed in to GitHub Copilot in VS Code.
- Open GitHub Copilot Chat and switch to Agent Mode.
- Try one of the prompts above — or just say:
@UI Test Smoke test my staging site at https://staging.example.com
Settings
| Setting |
Default |
Purpose |
uiTestAgent.autoInstallPrompts |
true |
Auto-copy the agent + prompt files to your prompts folder on activation. Locally edited files are preserved. |
uiTestAgent.enableChromeDevToolsMcp |
true |
Enable the built-in browser engine. Disable only if you use a custom external setup. |
uiTestAgent.chromeDevToolsMcpVersion |
latest |
Pin a specific browser engine build (advanced). |
uiTestAgent.chromeExecutablePath |
"" |
Absolute path to a Chrome / Chromium / Edge binary. Leave empty for auto-detect. |
uiTestAgent.chromeChannel |
"" |
Choose a Chrome release channel: stable / beta / canary / dev. |
Commands
- UI Test Agent: Install / Update Prompt Files — Force a re-install / update.
- UI Test Agent: Open Prompts Folder — Reveal the install location in your OS file explorer.
- UI Test Agent: Remove Installed Prompt Files — Uninstall the bundled files (preserves locally edited copies).
- UI Test Agent: Show Welcome / Usage — Re-open the welcome page.
- UI Test Agent: Show Browser Engine Status — Diagnostic info about the agent's browser runtime.
- UI Test Agent: Check Environment — Probe Node and the browser, then report what was found.
How file install behaves
- First install: writes the agent + 8 prompt files into your VS Code user
prompts/ folder.
- Extension upgrades: silently updates files only if your local copy still matches the previously installed version. Files you have edited are preserved untouched.
- Force update: run UI Test Agent: Install / Update Prompt Files to overwrite local edits.
- Uninstall command: removes only files that match the last installed version. Your edits are never deleted.
Safety guarantees
The bundled agent is read-only on application source code. Its file-write capability is whitelisted to test/report folders only — it can scaffold and write reports, but never modifies the product it tests. Same-origin crawls are capped at 25 pages by default. Real credentials and destructive actions are refused unless explicitly authorized.
License
MIT — see LICENSE.
