How do I install the Browser skill?

Run npx skillmds@latest add dreamlab-ai/browser in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Browser safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Browser?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Browser free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Browser?

dreamlab-ai (@dreamlab-ai) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Browser by dreamlab-ai — Agent Skill

Name: Browser
Author: dreamlab-ai

Browser

Drive a real Chrome via the browsercontainer sidecar over MCP SSE. Use when a task needs a live browser — navigate, click, fill forms, screenshot, read the accessibility tree, run JavaScript in-page, or validate WebGPU/WebGL rendering. Canonical owner of the sidecar connection details the chrome-cdp / playwright / browser-automation skills reference.

dreamlab-ai 2807ef2 2 files · 5.3 KB Updated Sep 17, 2026

File contents

Browser Automation Skill

All browser automation runs on the external browsercontainer sidecar via chrome-devtools-mcp (40+ tools) over MCP SSE. No local browser is installed in the agentbox image.

Connection (canonical)

This is the canonical sidecar-connection block; the chrome-cdp, playwright, and browser-automation skills point here rather than restating it.

MCP SSE:  http://browsercontainer:8931/sse   (chrome-devtools-mcp)
CDP:      browsercontainer:9223              (raw Chrome DevTools Protocol, socat proxy, in-network)
VNC:      localhost:5903                     (visual debugging, Display :2)

9222 is the host-mapped port (socat rebinds Chrome's localhost-only :9222 to :9223 in-network); use it only from the host, never from inside agentbox.

Auto-registered at boot as browser-gpu in .mcp.json. Manual registration:

claude mcp add browser-gpu --transport sse http://browsercontainer:8931/sse

When To Use

Page navigation, clicking, typing, form fills
Screenshots and accessibility snapshots
JavaScript evaluation in page context
WebGPU/WebGL rendering validation
Console log monitoring
Multi-tab workflows
Mermaid diagram rendering (via /render-mermaid HTTP endpoint; see mermaid-diagrams skill)

When Not To Use

Fetching page content without interaction -- use web-summary or gemini-url-context
API testing without a browser -- use curl or httpx
Raw CDP protocol scripting -- use the chrome-cdp skill
QE-grade typed assertions, visual-diff baselines -- use qe-browser

Key Tools

`browser_snapshot` (preferred for LLM interaction)

Returns an accessibility tree -- structured, deterministic, no vision model needed.

`browser_take_screenshot`

Capture viewport or full-page screenshot as PNG/JPEG.

`browser_navigate`

Navigate to a URL.

`browser_click` / `browser_type` / `browser_fill_form`

Interact with page elements.

`browser_evaluate`

Execute JavaScript in the page context.

`browser_console_messages`

Read browser console output.

Quick Start

browser_navigate({ url: "https://example.com" })
browser_snapshot()
browser_take_screenshot({ filename: "page.png", fullPage: true })

Sidecar Management

agentbox.sh browsercontainer up        # start
agentbox.sh browsercontainer health    # check all 5 services
agentbox.sh browsercontainer cdp       # list CDP tabs
agentbox.sh browsercontainer shell     # shell into container
agentbox.sh browsercontainer rebuild   # full rebuild

Health Check

curl -s http://browsercontainer:8931/health
curl -s http://browsercontainer:9223/json/list | jq '.[].url'

LaTeX and Diagram Workflows

Rendering Mermaid .mmd files (works around the broken Nix mmdc) and spot-checking compiled LaTeX/PDF pages via the sidecar are covered in references/latex-diagram-workflows.md.

---name: browserdescription: Drive a real Chrome via the browsercontainer sidecar over MCP SSE. Use when a task needs a live browser — navigate, click, fill forms, screenshot, read the accessibility tree, run JavaScript in-page, or validate WebGPU/WebGL rendering. Canonical owner of the sidecar connection details the chrome-cdp / playwright / browser-automation skills reference.---# Browser Automation SkillAll browser automation runs on the external `browsercontainer` sidecar via`chrome-devtools-mcp` (40+ tools) over MCP SSE. No local browser is installedin the agentbox image.## Connection (canonical)This is the canonical sidecar-connection block; the `chrome-cdp`, `playwright`,and `browser-automation` skills point here rather than restating it.```MCP SSE: http://browsercontainer:8931/sse (chrome-devtools-mcp)CDP: browsercontainer:9223 (raw Chrome DevTools Protocol, socat proxy, in-network)VNC: localhost:5903 (visual debugging, Display :2)```9222 is the host-mapped port (socat rebinds Chrome's localhost-only :9222 to :9223in-network); use it only from the host, never from inside agentbox.Auto-registered at boot as `browser-gpu` in `.mcp.json`. Manual registration:```bashclaude mcp add browser-gpu --transport sse http://browsercontainer:8931/sse```## When To Use- Page navigation, clicking, typing, form fills- Screenshots and accessibility snapshots- JavaScript evaluation in page context- WebGPU/WebGL rendering validation- Console log monitoring- Multi-tab workflows- Mermaid diagram rendering (via `/render-mermaid` HTTP endpoint; see `mermaid-diagrams` skill)## When Not To Use- Fetching page content without interaction -- use `web-summary` or `gemini-url-context`- API testing without a browser -- use `curl` or `httpx`- Raw CDP protocol scripting -- use the **chrome-cdp** skill- QE-grade typed assertions, visual-diff baselines -- use **qe-browser**## Key Tools### `browser_snapshot` (preferred for LLM interaction)Returns an accessibility tree -- structured, deterministic, no vision model needed.### `browser_take_screenshot`Capture viewport or full-page screenshot as PNG/JPEG.### `browser_navigate`Navigate to a URL.### `browser_click` / `browser_type` / `browser_fill_form`Interact with page elements.### `browser_evaluate`Execute JavaScript in the page context.### `browser_console_messages`Read browser console output.## Quick Start```javascriptbrowser_navigate({ url: "https://example.com" })browser_snapshot()browser_take_screenshot({ filename: "page.png", fullPage: true })```## Sidecar Management```bashagentbox.sh browsercontainer up # startagentbox.sh browsercontainer health # check all 5 servicesagentbox.sh browsercontainer cdp # list CDP tabsagentbox.sh browsercontainer shell # shell into containeragentbox.sh browsercontainer rebuild # full rebuild```## Health Check```bashcurl -s http://browsercontainer:8931/healthcurl -s http://browsercontainer:9223/json/list | jq '.[].url'```## LaTeX and Diagram WorkflowsRendering Mermaid `.mmd` files (works around the broken Nix `mmdc`) andspot-checking compiled LaTeX/PDF pages via the sidecar are covered in[`references/latex-diagram-workflows.md`](references/latex-diagram-workflows.md).

Frequently asked questions