QR image (PNG or SVG)

Owner-only. Returns a QR code image that encodes the link's qr_tracking_url (tagged short URL; ASCII host in the matrix). Default format PNG size 512. format=png|svg. PNG size is 256, 512, or 1024 (SVG ignores size). Requires a session cookie or an API key with links:read. An OAuth access token is not accepted. Anon → 401. Other-user / unowned → 404. Destination is never fetched or encoded. Fetching it does not record a visit. MCP create_qr may also return a short-lived image_url. Returns the stored link's QR as PNG, or SVG when requested, with a short-lived image URL where available. The QR encodes qr_tracking_url. Where an image is not displayed, image_url (when present) or the short link reaches the same code.