browser_eval

MCP tool from Byob by wxtsky

Run JavaScript on the page (off by default)

How to use it

browser_eval is exposed by the Byob MCP server. Add the server to your MCP client (Claude Desktop, Cursor, Windsurf and others), and the browser_eval tool becomes available to the model automatically. See the full listing for setup details and every tool this server provides.

Install Byob

$claude mcp add byob -s user -- /path/to/tsx /path/to/byob-mcp.ts

FULL BYOB LISTING

Other tools in Byob (39)

Click a button or link

browser_clipboard_read_text

Read plain text from the system clipboard.

browser_close_tab

Close a tab by tabId

browser_download_images

Download all images from a page

Drag the mouse from one point to another (linear interpolation).

browser_emulate_device

Emulate mobile/tablet viewport / DPR / touch / UA.

browser_extract_table

Pull <table> elements as JSON

browser_get_console_logs

Snapshot console.log / warn / error

browser_get_cookies

Export cookies for curl / scripts

browser_get_html

Get raw HTML of an element or the whole page

browser_get_js_dialog

Inspect an alert / confirm / prompt without resolving it.

browser_get_performance

Page Web Vitals + navigation timing.

browser_get_storage

Read localStorage / sessionStorage for an origin.

browser_go_back

Go back one step in browser history

browser_go_forward

Go forward one step in browser history

browser_handle_js_dialog

Explicitly accept or dismiss a JavaScript dialog.

browser_history

Search Chrome history with optional terms and date bounds.

Hover the mouse over an element to trigger tooltips/menus

browser_intercept_start

Start a stateful request-interception session.

browser_intercept_stop

Stop a browserinterceptstart session and return hit stats.

browser_list_tabs

List all open tabs

browser_navigate

Open a URL in a new or existing tab

browser_new_tab

Create an empty or pre-navigated background tab.

browser_press_key

Send a keyboard key (Enter, Escape, F5, ArrowDown, ...)

browser_print_pdf

Save current page as PDF (default ~/.byob/pdfs/).

Open a page, scroll through, read all text

browser_read_markdown

Same, returns clean markdown (no nav/ads)

Reload a tab and wait for it to finish loading.

browser_screenshot

Screenshot → saved to disk

Scroll to top/bottom, an element, or a Y coordinate

Choose an option in a native <select>

browser_set_cookies

Write a cookie via chrome.cookies.set (CHIPS-aware).

browser_snapshot

Get a compact accessibility tree with reusable element references.

browser_start_record_network

Start recording HTTP + WebSocket traffic

browser_stop_record_network

Stop recording, export JSON or HAR

browser_switch_tab

Switch to a tab

Type into an input (optionally press Enter)

browser_upload_file

Upload local files to <input type="file">.

browser_wait_for

Wait for an element to appear