Images and videos

Adding media is two steps: upload the file, then use its id in a post.

curl -X POST "$BULKIT_URL/media" \
  -H "x-api-key: $BULKIT_API_KEY" \
  -F "file=@./launch-banner.png"

{
  "id": "clx3k2p9q0001abcd1234efgh",
  "fileName": "launch-banner.png",
  "mimeType": "image/png",
  "size": 184320,
  "altText": null,
  "url": "https://…",
  "createdAt": "2026-08-04T09:30:00.000Z"
}

{
  "intent": "now",
  "channels": [
    {
      "channelId": "CHANNEL_ID",
      "blocks": [
        {
          "content": "Our new logo!",
          "mediaIds": ["MEDIA_ID"],
          "mediaAltText": { "MEDIA_ID": "A green heart logo on a white background" }
        }
      ]
    }
  ]
}

Allowed files

Each platform accepts only some of these. Check limits.acceptedMimeTypes, limits.maxMedia and limits.requiresMedia on GET /platforms. If requiresMedia is true, a post on that platform must have at least one file.

Good to know

• Use the id, not the url. The url is temporary and changes on every response. Do not save it.
• Files count towards your storage. Deleting a file with DELETE /media/{id} frees the space right away.
• Deleting a file does not remove it from posts that are already live. But a scheduled post that uses it will fail.
• GET /media lists every file in your library.