browser

Browser extensionFull

The SuperCapture browser extension's connections, a tab's geometry, and the headless browser for capture runs with no one at the screen. Nothing on a page is clicked or typed into: an agent that needs to drive a browser uses its own browser tools.

Needs the Full level, which is the default for any client holding the bearer token.

Parameters

Name	Type	Required	Description
action	string one of "status", "viewport", "element_bounds", "launch", "close"	yes	What to do. status: The browser extensions and headless browser connected, each with its browser, version and build. viewport: A tab's viewport size and scroll height (the active tab, or the one tab_title / tab_url names). (tab_title, tab_url) element_bounds: Where an element is in a tab's viewport, by CSS selector (getBoundingClientRect). Reads only. (selector, tab_title, tab_url) launch: Start a headless Chromium with the SuperCapture extension, and return when it has connected; capture page_visible / page_full then reach its tab. url opens a page (http(s), or a file:/// HTML file in the temp folder), which the user is asked about first, as for capture_url. Needs Chromium (brew install chromium). (url, width, height) close: Close the headless browser.
tab_title	string	no	viewport, element_bounds: a tab title substring (default the active tab).
tab_url	string	no	viewport, element_bounds: or a tab URL substring: a tab whose own host or path it names is preferred; include a scheme (https://...) to require an exact origin.
selector	string	no	element_bounds: a CSS selector.
url	string	no	launch: a page to open, http:// or https://, or a file:/// HTML file in the temp folder.
width	integer	no	launch: the viewport's width in pixels (default 1800).
height	integer	no	launch: the viewport's height in pixels (default 1200).

Example

A JSON-RPC call to POST http://localhost:21516/mcp with the bearer token, filling in the required parameters:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "browser",
    "arguments": {
      "action": "status"
    }
  }
}

See the MCP server overview for how to connect a client and where the token lives.