Browser Automation with Playwright MCP (Metabase)

A Playwright MCP server is configured in .mcp.json. Load the tool schemas first with ToolSearch: select:mcp__playwright__browser_navigate,mcp__playwright__browser_snapshot,mcp__playwright__browser_click,mcp__playwright__browser_fill,mcp__playwright__browser_type,mcp__playwright__browser_press_key,mcp__playwright__browser_hover,mcp__playwright__browser_take_screenshot,mcp__playwright__browser_close

If ToolSearch says "MCP servers still connecting," wait a few seconds and retry — the server takes a moment to start on first use.

Core pattern: Snapshot → Act → Check

browser_snapshot — see what's on screen, get element refs
Act — browser_click, browser_fill, browser_type, etc. using refs from the snapshot
Check the inline response — every action returns a snapshot in its response. Read it.

When to take a separate browser_snapshot after acting:

The inline response snapshot looks wrong, empty, or unchanged — take a fresh one (async rendering may not have completed)
You need refs for your NEXT action — the inline snapshot's refs are valid, use them directly
You're unsure if the action worked — take one more snapshot to confirm

When you do NOT need a separate snapshot after acting:

The inline response already shows the expected change (e.g., you clicked a link and the response shows the new page)
You're about to take a screenshot anyway (browser_take_screenshot shows the current state)
You're doing a chain of actions on the same form (e.g., filling multiple fields) — snapshot once at the end, not after each fill

Element refs go stale after every action. Use refs from the most recent snapshot or inline response — never from an earlier one.

How to interact with Metabase's UI components

Metabase uses Mantine UI components. Most interactions work with a plain browser_click. The hover-before-click pattern is only needed for specific component types.

Regular buttons, links, form inputs, checkboxes, tabs: Just browser_click them directly. No hover needed.

Buttons that open dropdown menus (e.g., "+ New", "..." action menus, filter type pickers): These use Mantine's <Menu> component which has a race condition with direct clicks. Hover before clicking these:

browser_hover on the button
browser_click on the button
Check the inline response — if the menu appeared, use its refs directly

How to tell if a button opens a dropdown menu: it usually has a chevron/arrow icon, a "..." label, or is labeled as creating something new (like "+ New"). If unsure, try a direct click first — if it doesn't work, retry with hover.

Select and dropdown components (e.g., database picker, column picker): Mantine Select/MultiSelect are NOT native <select> elements. browser_select_option will NOT work. Instead:

browser_click on the input/trigger
browser_click on the option you want (use refs from the inline response)

You can also type into the input to filter options before clicking.

Modals and dialogs: To dismiss: browser_click the close/action button, or browser_press_key with Escape.

⚠️ Mantine Escape-inside-modal trap: Pressing Escape while focus is inside a Mantine popover/Select/MultiSelect that is itself nested in a modal closes the entire modal and discards every form field you've already filled. To dismiss just an open dropdown, prefer browser_click outside the dropdown (or click another field). Only press Escape when you actually want the whole modal gone.

Mantine portals + scoped snapshots: Mantine renders dropdowns, popovers, and tooltips into a portal at <body> level — they are NOT children of the [role=dialog] element. If you scope browser_snapshot to the modal, dropdown options will be missing. Take a full-page snapshot when interacting with portaled content.

Login

browser_navigate to http://localhost:$MB_JETTY_PORT/auth/login
browser_snapshot → browser_fill email and password → browser_click sign-in button
browser_navigate to http://localhost:$MB_JETTY_PORT/ — always navigate explicitly to the home page after login. Do NOT rely on the login redirect alone. The redirect can leave the browser session in a state where clicks don't register.
browser_snapshot to confirm you're logged in

Quick login via API (alternative)

Get a session token via API and set it as a cookie — faster than filling the login form:

./bin/mage -bot-api-call /api/session --method POST --body '{"username":"<email>","password":"<password>"}'

Extract the id from the response, then use browser_evaluate with script:

document.cookie = 'metabase.SESSION=<token>;path=/'

Then browser_navigate to the target page. Use the credentials from ./bin/mage -bot-server-info.

When clicks don't work

Take a fresh snapshot (async rendering). 2. Try hover + click (menu triggers). 3. Try keyboard (focus + Enter). 4. After 3 attempts, report and move on.

Rules

Always use http://localhost:$MB_JETTY_PORT
Close the browser when done
Use inline response snapshots when sufficient — only take separate browser_snapshot when needed
Browser is pre-configured: 1440x900 viewport, full snapshot mode, isolated session, 10s action timeout

playwright-mcp-metabase