The agent talks to this over stdio. The capture happens in a Chrome you are already signed in to, which means a page behind a login is a page you are logged into. Nothing leaves the machine.

This package is four tools over @page-scanner/cli, which is where the bridge, the pairing and the daemon actually live. If you want the same thing at a shell prompt, install that instead; the two share one pairing and one daemon, so they can be used at the same time.

Setup

1. Point the agent at the server. For Claude Code:

claude mcp add page-scanner -- npx -y @page-scanner/mcp

Or as an mcpServers block, which Claude Desktop reads from claude_desktop_config.json and Codex and others read from .mcp.json:

{
  "mcpServers": {
    "page-scanner": {
      "command": "npx",
      "args": ["-y", "@page-scanner/mcp", "serve"]
    }
  }
}

2. Get a pairing. Ask the agent to run the pair tool, or do it yourself:

npx @page-scanner/mcp pair

It prints a port and a token and saves them to ~/.page-scanner/config.json. On macOS and Linux that file is owner-readable only; on Windows it is not, because NTFS does not implement the mode it is written with. See the CLI's README for how to restrict it on a shared machine.

3. Pair Chrome. Open the Page Scanner settings page (the gear in the editor toolbar, or chrome://extensions then Details then Extension options). Under Local agents:

give the browser a name, so an agent can tell your profiles apart ("work", "personal"),
paste the port and the token,
press Connect.

Chrome runs a separate copy of the extension in every profile, so repeat that for each profile you want reachable. They share the port and token and identify themselves by name.

page-scanner-mcp status says whether a pairing exists and whether anything is connected. pair --rotate issues a new token, which also invalidates the old one everywhere.

A note on the `pair` tool

The pair tool returns the token to the agent, which means it lands in the conversation, and a transcript is a place secrets should not be. It is there because being told to install a second program before anything works is a bad first five minutes. If that trade-off is wrong for you, run npx @page-scanner/mcp pair in a terminal instead and paste the token into Chrome yourself; the agent never needs to see it.

Updating

Both setups run npx -y @page-scanner/mcp, which asks npm for the newest version each time the client starts the server. Restart the client, or start a new Claude Code session, to pick one up. The daemon restarts itself on the new version and the pairing carries over.

If you also installed the command line globally, update it at the same time with npm install -g @page-scanner/cli@latest. A daemon of one version is replaced by a client of any other, so the two would keep replacing each other's daemon.

Tools

pair Writes the pairing and returns the port and token to paste into Chrome. See the note above.

list_browsers The Chrome profiles paired and connected right now, with the name you gave each one. Start here when more than one is connected.

list_tabs The windows and open tabs of one browser. Tabs carry the windowId they belong to, and windows say which is focused, so an agent can pick a window as well as a tab. Takes an optional browserId, which is only required when more than one browser is connected, and an optional waitSeconds.

scan_page Captures a page and writes it to disk. Returns the absolute path.

Argument	Meaning
`browserId`	Which browser. Optional when only one is connected.
`tabId`	A tab from `list_tabs`. Give this or `url`, not both.
`url`	Opens a background tab there, captures it, closes it again.
`windowId`	Which window to open `url` in. Ignored with `tabId`.
`format`	`pdf` (default), `png`, `jpeg`.
`pageSize`	PDF only. `a4` (default) and `letter` slice onto printable sheets with a half-inch margin; `auto` is one page the size of the capture.
`quality`	JPEG only, 0.1 to 1.
`videoHandling`	`frame` keeps a video's paused frame, `blank` leaves its area empty.
`openEditor`	Also leave the capture open in a Page Scanner editor tab.
`outputPath`	A file, or a directory to keep the suggested name. Defaults to the cwd.
`waitSeconds`	How long to wait for a browser to connect. 0 fails immediately.

A PDF from a vector capture keeps real, selectable text. The result says selectableText: true when that is what you got, and carries a truncated object when the page was larger than Page Scanner will capture and the file is missing part of it.

What an agent can do with this, and what it cannot

It can list the addresses of every tab you have open, capture any of them, and open an address of its own choosing to capture that. It captures whatever the browser renders, which on a logged-in tab means whatever you are logged in as.

It cannot reach anything without the token, and the token only exists once you have pasted it into a browser and pressed Connect. Turning the toggle off closes the connection immediately.

Three checks run on every connection: the Origin has to be a chrome-extension:// one, which stops a web page in any browser talking to the server; the first frame has to carry the token, which stops any other program on the machine doing so; and the protocol number has to match, so an extension and a server that disagree say so instead of misbehaving.

Limits

A scan attaches chrome.debugger, so Chrome shows its "Page Scanner started debugging this browser" bar for as long as the scan takes. That is Chrome's notice and cannot be suppressed. Unattended, it will appear without you having asked for it.
A tab with DevTools open cannot be captured at all: only one debugger can attach at a time.
There is no raster fallback for an agent scan. The fallback needs activeTab, which requires a click, so an agent scan of a page the vector capture cannot handle fails loudly instead.
chrome:// pages, the Web Store and other extensions' pages are off limits to any extension.
The crop is always the whole page. An agent has no preview to crop against.