Chrome DevTools AXI

When to use

Use this skill when the task specifically needs chrome-devtools-axi or a Chrome DevTools Protocol browser controlled from the terminal:

• the user says chrome-devtools-axi, chrome-devtools-mcp, AXI browser automation, or asks to run npx -y chrome-devtools-axi
• an agent needs a compact accessibility snapshot with actionable refs and command suggestions
• browser work needs console logs, network requests, screenshots, Lighthouse, heap snapshots, or performance traces in the same CLI surface
• the existing Hermes/browser stack is unavailable or the user explicitly prefers this tool

Do not use it for ordinary web search, curl-able pages, static extraction, or stealth/anti-detection work. Use Camofox/Camoufox only when cloaking is load-bearing. Use built-in browser tools when the task is already solved there and the user did not name chrome-devtools-axi.

Mental model

chrome-devtools-axi is an npm CLI wrapper around chrome-devtools-mcp. The first command starts a persistent local bridge, then later invocations reuse the same Chrome/DevTools session. Output is AXI/TOON-style: page metadata, accessibility snapshots, element refs, and next-step suggestions.

State lives under ~/.chrome-devtools-axi/, including the bridge PID and snapshot-generation counter.

Setup and verification

The skill only teaches the agent how to use the tool. The actual CLI is the npm package chrome-devtools-axi; source repo: https://github.com/kunchenguid/chrome-devtools-axi

Prefer npx for one-off use so the CLI is installed on demand:

npx -y chrome-devtools-axi --help
npx -y chrome-devtools-axi

Use a global install only when repeated shell use matters:

npm install -g chrome-devtools-axi
chrome-devtools-axi --help

Before relying on the tool, verify the live CLI rather than assuming docs are current:

npx -y chrome-devtools-axi --version
npx -y chrome-devtools-axi --help

If the home view says browser: no active session, open a page:

npx -y chrome-devtools-axi open https://example.com

Core workflow

1. Start from the current state or open a page:

   npx -y chrome-devtools-axi
   npx -y chrome-devtools-axi open https://example.com
   

2. Use the latest snapshot refs exactly as printed. They look like @g\x3CN>:... and may include underscores, for example @g4:1_3:

   npx -y chrome-devtools-axi click @\x3Cuid>
   npx -y chrome-devtools-axi fill @\x3Cuid> "search text"
   npx -y chrome-devtools-axi press Enter
   

3. Re-snapshot after every state-changing action:

   npx -y chrome-devtools-axi snapshot
   

4. Inspect browser diagnostics when debugging app behavior:

   npx -y chrome-devtools-axi console --type error --limit 20
   npx -y chrome-devtools-axi network --type fetch --limit 20
   npx -y chrome-devtools-axi network-get \x3Cid> --response-file /tmp/response.json
   

5. Stop the bridge when preserving the browser session is not useful:

   npx -y chrome-devtools-axi stop
   

Ref discipline

Refs include a generation prefix such as @g1:1_7. Treat refs as scoped to the latest accessibility snapshot.

Hard rules:

• Pass refs back exactly as printed, including @ and the generation prefix.
• Re-snapshot after navigation, click, form submit, scroll, dialog handling, upload, drag, JS mutation, page selection, or resize.
• If a command fails with STALE_REF, do not retry the same ref blindly. Snapshot again, find the new ref, then retry.
• Prefer refs over CSS selectors or DOM guessing. Use eval only when the accessibility surface cannot expose the needed state.

Command usage policy

Do not treat this skill as the CLI reference. For exact flags and subcommands, run the live help first:

npx -y chrome-devtools-axi --help

Use this skill for durable agent judgment: when to choose the tool, how to sequence work, which commands are high leverage, how to verify actions, and which modes are privacy-sensitive.

Best-practice scenarios

Explore or verify a page. Open the URL, snapshot it, then verify with URL, title, DOM, or screenshot evidence before reporting success:

npx -y chrome-devtools-axi open https://example.com
npx -y chrome-devtools-axi snapshot
npx -y chrome-devtools-axi eval "document.title"
npx -y chrome-devtools-axi screenshot /tmp/page.png

Interact with a page or form. Use refs from the latest snapshot exactly as printed, then re-snapshot after each state-changing action:

npx -y chrome-devtools-axi click @\x3Cuid>
npx -y chrome-devtools-axi fill @\x3Cuid> "value"
npx -y chrome-devtools-axi press Enter
npx -y chrome-devtools-axi snapshot

Debug a web app. Check console and network before guessing. Save large request/response bodies to files instead of dumping them into chat:

npx -y chrome-devtools-axi console --type error --limit 20
npx -y chrome-devtools-axi network --type fetch --limit 20
npx -y chrome-devtools-axi network-get \x3Cid> --response-file /tmp/response.json

Use existing Chrome or logged-in state. Prefer a fresh isolated browser. Connect to an existing browser/profile only when the task requires it and the user has authorized that scope:

CHROME_DEVTOOLS_AXI_BROWSER_URL=http://127.0.0.1:9222 npx -y chrome-devtools-axi snapshot
CHROME_DEVTOOLS_AXI_AUTO_CONNECT=1 npx -y chrome-devtools-axi snapshot
CHROME_DEVTOOLS_AXI_USER_DATA_DIR="$HOME/.chrome-devtools-axi/profile" npx -y chrome-devtools-axi open https://example.com

Handle slow cold starts. If repeated commands are slow because the bridge is bootstrapping chrome-devtools-mcp through npx, use the CLI help's current CHROME_DEVTOOLS_AXI_MCP_PATH recipe rather than inventing a path.

Use visual/GPU-sensitive pages. For WebGL/WebGPU/GPU debugging, use headed mode and Chrome flags from the live help. Do not persist broad Chrome flags globally.

For run, emulate, Lighthouse, performance traces, heap snapshots, or less common flags, consult --help/upstream docs at the moment of use instead of copying examples from memory.

Existing Chrome, headed mode, and profiles

Use environment variables inline for a single command or process when possible. Do not persist them globally unless the user explicitly wants that behavior. Treat persistent profiles as privacy-sensitive. Do not browse authenticated accounts, export cookies, or inspect private content unless the user explicitly authorizes that scope.

Diagnostics and performance

For app debugging, prefer the CLI's console/network commands before guessing. Only run Lighthouse, traces, and heap snapshots when they materially help; they are slower and noisier than simple snapshots, console checks, and network lists.

Safety and privacy

• Do not run setup hooks unless the user explicitly asks to install ambient agent hooks. It mutates local agent configuration.
• Do not print CHROME_DEVTOOLS_AXI_WS_HEADERS; it may contain bearer tokens.
• Do not use a persistent CHROME_DEVTOOLS_AXI_USER_DATA_DIR casually; it can carry login state and browsing history.
• Do not claim a browser action succeeded until a fresh snapshot, URL/title, screenshot, console/network result, or DOM evaluation verifies it.
• Close pages or stop the bridge when done unless keeping state is useful for the user's next step.

Common failure handling

• No active session: run open \x3Curl>.
• Stale ref: run snapshot, find the new ref, retry once.
• Slow first command: the bridge may be bootstrapping chrome-devtools-mcp through npx. If repeated cold starts hurt, globally install chrome-devtools-mcp and use CHROME_DEVTOOLS_AXI_MCP_PATH as described in chrome-devtools-axi --help.
• Wrong tab: run pages, then selectpage \x3Cid> and snapshot.
• Need the user's normal Chrome: use CHROME_DEVTOOLS_AXI_AUTO_CONNECT=1 only when remote debugging is enabled and connecting to that browser is intentional.