Capture

Paired screenshot and accessibility snapshot from the same DOM epoch in one HTTP call. Use this when the model needs to read pixels AND act on refs in the same turn — the unpaired /screenshot + /snapshot sequence drifts when the page mutates between calls.

pinchtab capture -o /tmp/cap.jpg# Half-size image (snapshot/bounds unchanged)pinchtab capture --scale 0.5# Fail with 409 if the main frame navigates mid-capturepinchtab capture --require-pair# Full-document image; bounding boxes in page coordspinchtab capture --beyond-viewport# Scope to one element: image clips to it, snapshot subtree filters to it.# Bounding boxes are relative to the clipped image origin.pinchtab capture -s "#checkout-form"

# Default: file output, wait for page quiescence, bounds includedcurl "http://localhost:9867/capture"

Response (JSON)

{
  "status": "ok",
  "tabId": "tab_abc",
  "url": "https://example.com/checkout",
  "title": "Checkout",
  "capturedAt": "2026-05-29T15:44:12.431Z",
  "epoch": {
    "frameId": "8E2F...A1",
    "loaderId": "5C9D...0B",
    "domEpoch": "ep_..."
  },
  "pairing": {
    "navigated": false,
    "captureDurationMs": 312
  },
  "image": {
    "format": "jpeg",
    "path": "/.../state/captures/cap-20260529-154412.jpg",
    "bytes": 184223,
    "coordinateSpace": "viewport",
    "devicePixelRatio": 2,
    "viewport": { "w": 1440, "h": 900, "scrollX": 0, "scrollY": 0 }
  },
  "snapshot": {
    "filter": "interactive",
    "nodeCount": 14,
    "nodes": [
      {
        "ref": "e4", "role": "textbox", "name": "Email",
        "boundingBox": { "x": 520, "y": 312, "w": 280, "h": 36 },
        "visible": true
      }
    ]
  }
}

What pairing guarantees

The atomicity contract is “no main-frame navigation between the two CDP calls” — pairing.navigated flips to true when the main frame’s loaderId changes during the capture window. Drift inside the same document (React re-renders, IntersectionObserver mutations) is not detected; wait=stable reduces but does not eliminate it.

epoch.domEpoch is an opaque server-minted token cached on the tab’s ref-cache alongside the snapshot refs. Future action endpoints will accept an expectedEpoch query param to reject stale refs at use time.

Bounding boxes and coordinate space

When withBounds=true (the default), each snapshot node with a non-zero backend node id gets a boundingBox and a visible flag. The coordinate space depends on selector and beyondViewport:

• viewport (default): boxes are viewport-relative CSS pixels. The image is the visible viewport. image.devicePixelRatio tells you the ratio of image pixels to CSS pixels.
• clip (when selector is set): boxes are relative to the cropped image origin. The response also includes image.clip with the original document-relative clip rectangle.
• document (when beyondViewport=true): boxes use page coordinates (box.x and box.y include scroll offset). The image is the full document.

visible is true when the box has positive area and intersects the viewport — a cheap heuristic, not a strict occlusion check.

Useful flags

API Query Parameters

CLI

Related Pages

• Screenshot
• Snapshot
• Frame