twitter.media.image_video_exclusive - letmepost.dev

What it checks

If the same media array contains at least one item with kind: "image" and at least one with kind: "video", preflight fails before bytes resolve.

Why

X enforces this at the API level — /2/tweets rejects mixed-media payloads. Catching it locally surfaces a clean rule id instead of a generic 400 from upstream.

Failure response

{
  "error": {
    "code": "preflight_failed",
    "rule": "twitter.media.image_video_exclusive",
    "platform": "twitter",
    "message": "Cannot attach both images and video to the same tweet — X requires picking one.",
    "remediation": "Split into separate tweets: one with images, one with the video."
  }
}

Remediation

Two tweets in a reply chain — first one with images, second one with the video, threaded via twitter.replyToTweetId:

{ "media": [{ "kind": "image", "mediaId": "med_…" }] }

{
  "media": [{ "kind": "video", "mediaId": "med_…" }],
  "twitter": { "replyToTweetId": "<id of first tweet>" }
}

twitter.media.count_max