Send them in options, keyed by network, on POST /api/post and POST /api/schedule (or inside a per_platform draft). A network ignores the options of the others.
Who sees the post. Words also work: public, followers, friends, private. When TikTok does not allow the value for this creator, the closest allowed level that is not more open is used and the result says so. Default SELF_ONLY. One of: PUBLIC_TO_EVERYONE, FOLLOWER_OF_CREATOR, MUTUAL_FOLLOW_FRIENDS, SELF_ONLY.
options.tiktok.disable_comment
boolean
Default false.
options.tiktok.disable_duet
boolean
Videos only. Default false.
options.tiktok.disable_stitch
boolean
Videos only. Default false.
options.tiktok.brand_organic_toggle
boolean
Discloses that the post promotes the creator's own business. Default false.
options.tiktok.branded_content_toggle
boolean
Discloses a paid partnership with a third party. Cannot be private. Default false.
Posted as the author's first comment right after the post (where a link goes without hurting reach). A failed comment is retried later; the post is never re-sent.
options.linkedin.document_url
string (uri)
A PDF, PPT or DOC published as a document (carousel) post.
One more X post published as a reply under the last post of the chain: under the main post, or under the last post of per_platform.x.thread when there is one (the usual place for a link). At most 280 characters as X counts them (a link counts 23, an emoji 2); longer is refused with code bad_x_thread before anything goes out. It is an X post: 1 X credit, 10 with a link, and it counts toward the daily X limit. Also accepted as per_platform.x.reply.
Before you choose a TikTok privacy level, GET /api/tiktok/creator-info returns the levels TikTok allows for the connected creator.