browser skill

---
name: browser-automation
description: |
  Vision-driven browser automation using Midscene. Operates entirely from screenshots — no DOM or accessibility labels required. Can interact with all visible elements on screen regardless of technology stack.

  Opens a new browser tab for each target URL via Puppeteer (headless Chrome).

  Use this skill when the user wants to:
  - Browse, navigate, or open web pages
  - Scrape, extract, or collect data from websites
  - Fill out forms, click buttons, or interact with web elements
  - Verify, validate, or test frontend UI behavior
  - Take screenshots of web pages
  - Automate multi-step web workflows
  - Run browser automation or check website content


  Powered by Midscene.js (https://midscenejs.com)
allowed-tools:
  - Bash
---

# Browser Automation

> **CRITICAL RULES — VIOLATIONS WILL BREAK THE WORKFLOW:**
>
> 1. **Never run midscene commands in the background.** Each command must run synchronously so you can read its output (especially screenshots) before deciding the next action. Background execution breaks the screenshot-analyze-act loop.
> 2. **Run only one midscene command at a time.** Wait for the previous command to finish, read the screenshot, then decide the next action. Never chain multiple commands together.
> 3. **Allow enough time for each command to complete.** Midscene commands involve AI inference and screen interaction, which can take longer than typical shell commands. A typical command needs about 1 minute; complex `act` commands may need even longer.
> 4. **Always report task results before finishing.** After completing the automation task, you MUST proactively summarize the results to the user — including key data found, actions completed, screenshots taken, and any relevant findings. Never silently end after the last automation step; the user expects a complete response in a single interaction.

Automate web browsing using `npx @midscene/web@1`. Launches a headless Chrome via Puppeteer that **persists across CLI calls** — no session loss between commands. Each CLI command maps directly to an MCP tool — you (the AI agent) act as the brain, deciding which actions to take based on screenshots.

## When to Use

Use this skill when:
- The user wants to browse or navigate to a specific URL
- You need to scrape, extract, or collect data from websites
- You want to verify or test frontend UI behavior
- The user wants screenshots of web pages

If you need to preserve login sessions or work with the user's existing browser tabs, use the **Chrome Bridge Automation** skill instead.

## Prerequisites

Midscene requires models with strong visual grounding capabilities. The following environment variables must be configured — either as system environment variables or in a `.env` file in the current working directory (Midscene loads `.env` automatically):

```bash
MIDSCENE_MODEL_API_KEY="your-api-key"
MIDSCENE_MODEL_NAME="model-name"
MIDSCENE_MODEL_BASE_URL="https://..."
MIDSCENE_MODEL_FAMILY="family-identifier"
```

Example: Gemini (Gemini-3-Flash)

```bash
MIDSCENE_MODEL_API_KEY="your-google-api-key"
MIDSCENE_MODEL_NAME="gemini-3-flash"
MIDSCENE_MODEL_BASE_URL="https://generativelanguage.googleapis.com/v1beta/openai/"
MIDSCENE_MODEL_FAMILY="gemini"
```

Example: Qwen 3.5

```bash
MIDSCENE_MODEL_API_KEY="your-aliyun-api-key"
MIDSCENE_MODEL_NAME="qwen3.5-plus"
MIDSCENE_MODEL_BASE_URL="https://dashscope.aliyuncs.com/compatible-mode/v1"
MIDSCENE_MODEL_FAMILY="qwen3.5"
MIDSCENE_MODEL_REASONING_ENABLED="false"
# If using OpenRouter, set:
# MIDSCENE_MODEL_API_KEY="your-openrouter-api-key"
# MIDSCENE_MODEL_NAME="qwen/qwen3.5-plus"
# MIDSCENE_MODEL_BASE_URL="https://openrouter.ai/api/v1"
```

Example: Doubao Seed 2.0 Lite

```bash
MIDSCENE_MODEL_API_KEY="your-doubao-api-key"
MIDSCENE_MODEL_NAME="doubao-seed-2-0-lite"
MIDSCENE_MODEL_BASE_URL="https://ark.cn-beijing.volces.com/api/v3"
MIDSCENE_MODEL_FAMILY="doubao-seed"
```

Commonly used models: Doubao Seed 2.0 Lite, Qwen 3.5, Zhipu GLM-4.6V, Gemini-3-Pro, Gemini-3-Flash.

If the model is not configured, ask the user to set it up. See [Model Configuration](https://midscenejs.com/model-common-config) for supported providers.

## Commands

### Connect to a Web Page

```bash
npx @midscene/web@1 connect --url https://example.com
```

### Take Screenshot

```bash
npx @midscene/web@1 take_screenshot
```

After taking a screenshot, read the saved image file to understand the current page state before deciding the next action.

### Perform Action

Use `act` to interact with the page and get the result. It autonomously handles all UI interactions internally — clicking, typing, scrolling, hovering, waiting, and navigating — so you should give it complex, high-level tasks as a whole rather than breaking them into small steps. Describe **what you want to do and the desired effect** in natural language:

```bash
# specific instructions
npx @midscene/web@1 act --prompt "click the Login button and fill in the email field with '[email protected]'"
npx @midscene/web@1 act --prompt "scroll down and click the Submit button"

# or target-driven instructions
npx @midscene/web@1 act --prompt "click the country dropdown and select Japan"
```

### Disconnect

Disconnect from the page but keep the browser running:

```bash
npx @midscene/web@1 disconnect
```

### Close Browser

Close the browser completely when finished:

```bash
npx @midscene/web@1 close
```

## Workflow Pattern

The browser **persists across CLI calls** via a background Chrome process. Follow this pattern:

1. **Connect** to a URL to open a new tab
2. **Take screenshot** to see the current state, make sure the page is loaded.
3. **Execute action** using `act` to perform the desired action or target-driven instructions.
4. **Close** the browser when done (or **disconnect** to keep it for later)
5. **Report results** — summarize what was accomplished, present key findings and data extracted during the task, and list any generated files (screenshots, logs, etc.) with their paths

## Best Practices

1. **Always connect first**: Navigate to the target URL with `connect --url` before any interaction.
2. **Be specific about UI elements**: Instead of `"the button"`, say `"the blue Submit button in the contact form"`.
3. **Use natural language**: Describe what you see on the page, not CSS selectors. Say `"the red Buy Now button"` instead of `"#buy-btn"`.
4. **Handle loading states**: After navigation or actions that trigger page loads, take a screenshot to verify the page has loaded.
5. **Close when done**: Use `close` to shut down the browser and free resources.
6. **Never run in background**: Every midscene command must run synchronously — background execution breaks the screenshot-analyze-act loop.
7. **Batch related operations into a single `act` command**: When performing consecutive operations within the same page, combine them into one `act` prompt instead of splitting them into separate commands. For example, "fill in the email and password fields, then click the Login button" should be a single `act` call, not three. This reduces round-trips, avoids unnecessary screenshot-analyze cycles, and is significantly faster.
8. **Always report results after completion**: After finishing the automation task, you MUST proactively present the results to the user without waiting for them to ask. This includes: (1) the answer to the user's original question or the outcome of the requested task, (2) key data extracted or observed during execution, (3) screenshots and other generated files with their paths, (4) a brief summary of steps taken. Do NOT silently finish after the last automation command — the user expects complete results in a single interaction.

**Example — Dropdown selection:**

```bash
npx @midscene/web@1 act --prompt "click the country dropdown and select Japan"
npx @midscene/web@1 take_screenshot
```

**Example — Form interaction:**

```bash
npx @midscene/web@1 act --prompt "fill in the email field with '[email protected]' and the password field with 'pass123', then click the Log In button"
npx @midscene/web@1 take_screenshot
```

## Troubleshooting

### Connection Failures
- Ensure Chrome/Chromium is installed on the system (Puppeteer downloads its own by default).
- Check that no firewall blocks local Chrome debugging ports.

### API Key Errors
- Check `.env` file contains `MIDSCENE_MODEL_API_KEY=<your-key>`.
- Verify the key is valid for the configured model provider.

### Timeouts
- Web pages may take time to load. After connecting, take a screenshot to verify readiness before interacting.
- For slow pages, wait briefly between steps.

### Screenshots Not Displaying
- The screenshot path is an absolute path to a local file. Use the Read tool to view it.