Update a post

Update an existing draft or scheduled post by its ID. title sets the post-level title; on Facebook it's an alias for platformConfiguration.title (the video title), and either one updates both. Send null or an empty string to clear it. status may be DRAFT, SCHEDULED (requires a future scheduledAt, either in this request or already on the post), or PROCESSING (publish now). COMPLETED and FAILED are set only by the publisher. A new scheduledAt must not be in the past, whatever the status (422). media replaces the post's media and accepts the same items as create — a stored or public URL ({ url }) or a media library id ({ id }), so the media array from GET /v0/posts/{id} can be sent back as-is. parts (X and Mastodon only) replaces the post's thread with the same items create accepts — part media may also be a library { id }, so the parts array from GET /v0/posts/{id} round-trips — and an empty array removes the thread. On X, parts[0] is the opening tweet: sending parts without caption sets the caption to parts[0], and changing caption or media without parts updates parts[0] when it matched the old value. Posts that are already publishing, published, or failed can't be edited (409).