Viewport Commands

Viewport commands render a page at a specific screen size and device profile, then capture a PNG screenshot and the full rendered HTML. Each preset carries a CSS-pixel viewport, device pixel ratio, and (for mobile/tablet) a device-appropriate user-agent string. The captured artifacts are saved to the project folder alongside a JSON metadata sidecar.

All five viewport commands are Core tier.

/mobile <url>

Capture with an iPhone 14-class viewport and Mobile Safari user-agent.

The UA override causes the server to send mobile-specific markup and @media queries fire at the mobile breakpoint.

Output

CLI

crawlio cmd mobile https://stripe.com

MCP

{ "name": "slash_mobile", "arguments": { "url": "https://stripe.com" } }

Returns ViewportCaptureReport JSON with viewport.name: "mobile".

/tablet <url>

Capture with an iPad-class viewport and iPadOS Safari user-agent.

CLI

crawlio cmd tablet https://stripe.com

MCP

{ "name": "slash_tablet", "arguments": { "url": "https://stripe.com" } }

Returns ViewportCaptureReport JSON with viewport.name: "tablet".

/desktop <url>

Capture with a desktop-class viewport. The user-agent is not overridden (caller's default UA is preserved).

CLI

crawlio cmd desktop https://stripe.com

MCP

{ "name": "slash_desktop", "arguments": { "url": "https://stripe.com" } }

Returns ViewportCaptureReport JSON with viewport.name: "desktop".

/print <url>

Capture with a US Letter (8.5 x 11 in at 96 DPI) viewport and print stylesheet emulation. A JS bridge shims matchMedia('print') to always match, so CSS @media print rules apply and the resulting PNG reflects the print layout.

The emulatePrint flag is injected as a user script at .atDocumentStart. It forces window.matchMedia('print').matches to return true before the page's CSS is evaluated.

CLI

crawlio cmd print https://example.com/pricing

MCP

{ "name": "slash_print", "arguments": { "url": "https://example.com/pricing" } }

Returns ViewportCaptureReport JSON with viewport.name: "print".

/viewport <WxH> <url>

Capture with a custom viewport size. Width and height are specified as WxH (e.g. 830x360). Both dimensions are clamped to a minimum of 1 CSS pixel by the ViewportPreset initializer.

CLI

crawlio cmd viewport 830x360 https://example.com

MCP

{ "name": "slash_viewport", "arguments": { "url": "https://example.com", "width": 830, "height": 360 } }

Returns ViewportCaptureReport JSON with viewport.name: "custom".

Sidecar report

All viewport commands write a JSON sidecar to the project folder as viewport-{name}-{host}-{epoch}.json: