upload_video_creative

Upload videos directly to the Metadata platform library to create video creatives.
                Downloads videos from provided URLs and uploads them to the platform.

                ⚠️ VIDEO-ONLY: The downloaded file MUST have a `video/*` content-type
                (e.g. video/mp4, video/quicktime). GIFs and image formats are
                rejected — use `upload_image_creative` for those.

                ⚠️ WHEN YOU NEED TO CALL THIS:
                Call this BEFORE `create_update_video_ad` ONLY when you don't already
                have a videoLibraryId. If the user (or an earlier step) has
                already given you a creativeID for the video, skip the upload
                and pass that id straight to `create_update_video_ad`.

                WORKFLOW INTEGRATION (when an upload IS needed):
                1. Upload your video URL with this tool → response contains the integer `id` (the videoLibraryId).
                2. Pass that integer `id` as `creativeID` in `create_update_video_ad`.

                COMMON WORKFLOWS:
                - Upload existing video → Get videoLibraryId → Use as creativeID in `create_update_video_ad`.
                - For Reddit VIDEO ads, ALSO upload a thumbnail image via `upload_image_creative` and pass that image
                  library id as `redditThumbnailLibraryId` to `create_update_video_ad`.

                REQUIRED PARAMETERS:
                - videos: Array of video URLs to upload.

                OPTIONAL PARAMETERS:
                - thumbnail_library_id: Existing imageLibraryId to attach to the
                  uploaded video as its platform thumbnail. Most callers don't
                  need this — Reddit VIDEO ads handle thumbnails at ad-creation
                  time via `redditThumbnailLibraryId`, not here.

                VIDEO REQUIREMENTS:
                - URLs must be valid and publicly accessible.
                - Supported formats: MP4 (recommended), MOV, and other video/* MIME types.
                - For GIFs (image/gif): use `upload_image_creative` instead.

                RESPONSE FORMAT:
                Returns array of objects, one per video. `id` is returned as a
                string (the platform's library ids are integers but the upload
                response stringifies them); pass it to `create_update_video_ad` as an
                integer (Python `int(id)` if you need the cast).
                [
                    {
                        "url": "https://example.com/video.mp4",
                        "name": "video.mp4",
                        "id": "12345",                # videoLibraryId — use as creativeID in create_update_video_ad
                        "success": true
                    },
                    {
                        "url": "https://example.com/bad.mp4",
                        "name": "bad.mp4",
                        "id": null,
                        "success": false,
                        "error": "Download failed: Connection timeout"
                    }
                ]

                ERROR HANDLING:
                - If one upload fails, others continue.
                - Each result includes a success flag and (on failure) an error message.
                - A content-type that does not start with `video/` is rejected
                  with a clear error pointing the caller at `upload_image_creative`.