Post an image by URL

When the file is already online — a CDN, an object store, your CMS — name it instead of uploading it.

curl https://app.pubrivo.com/api/posts \
  -H "Authorization: Bearer $PUBRIVO_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "text": "New on the counter: blueberry buns.",
    "channelIds": ["'"$INSTAGRAM_CHANNEL_ID"'"],
    "scheduledAt": "2027-01-23T07:00:00Z",
    "media": [
      { "url": "https://cdn.example.com/blueberry-1.jpg", "altText": "Blueberry buns on a rack" },
      { "url": "https://cdn.example.com/blueberry-2.jpg", "altText": "One bun, cut open" }
    ]
  }'

Two images to Instagram make a carousel, in this order.

Pubrivo asks each address for its type and size straight away, and refuses the Post if either is not a JPEG, PNG, WebP, MP4 or MOV under 2 GB. It fetches the files before publishing; keep them at those addresses until then. See media by URL.