Media requirements | Chirio Docs

Media is passed by URL. Chirio never stores it:

URLs must be publicly reachable

Instagram and Threads fetch media from your URL at publish time, so anything behind auth, an expired signed URL, or a private bucket fails the target. For X and LinkedIn, Chirio downloads the bytes and re-uploads them — same requirement.

Not hosting media is deliberate: storage, CDN, scanning and retention policy are their own product, and you almost certainly already have somewhere to put a file.

Limits

The request-level cap is 10 media items, whatever the platform allows. On top of that:

Platform	Images	Video	Notes
Instagram	1–10, JPEG only	1 (single video = Reel)	Media is required; 2+ items publish as a carousel
Threads	0–10	video items allowed	Text-only posts are fine
X	up to 4	1	One video or up to 4 images, never both
LinkedIn	up to 10	1	2+ images publish as a multi-image post; one video or images

Violating any of these rejects the whole request with 400 invalid_post before anything publishes, naming the platform and the rule.

Video takes time

Video does not publish instantly anywhere. The platform processes the file first, and Chirio waits for it — up to roughly four minutes per item. A video-heavy carousel can therefore take several minutes in a single call. Two consequences:

Set a generous client timeout, and always send an Idempotency-Key so a timeout on your side is safe to retry. See Idempotency.
A slow item can time out and fail that target with media_processing_timeout. Retry just that target.

Ordering

mediaItems order is preserved. For carousels it is the slide order the reader sees — see Carousels.

Practical checklist

Serve media over HTTPS from a stable, public URL.
Keep the URL alive until the call returns — for video, that can be several minutes.
Use JPEG for Instagram images; PNG and WebP are refused.
Do not mix a video and images in one X or LinkedIn post.
If media uploads fail on X while text posts work, the connection predates X media permission — reconnect the account.