✦ Partner API
How to validate 1–20 slideshow image URLs before a MultiPost API call
Quick answer
Before sending a MultiPost slideshow, require type slideshow and an ordered imageUrls array containing one to twenty stable public URLs. Reject an empty list locally, preserve user-selected order, verify every URL without browser credentials and confirm that the exact Instagram, TikTok or Facebook target is currently connected.
How do you validate one to twenty slideshow images before a MultiPost API call?
Validate that type is slideshow andimageUrls contains between one and twenty public string URLs before calling MultiPost. An empty list produces a missing-media error, while more than twenty prepared images returns 400 too_many_images.
Preserve the intended order during validation. The array order becomes the visual sequence, so sorting URLs or removing duplicates without user confirmation can change the story of the slideshow.
What is the fast way to publish the validated slideshow with MultiPost?
Have the customer connect the exact social accounts in MultiPost, send the validated URLs from your server and use explicit platform-and-handle targets.
Partner API publishing requires Pro or Agency. Link to MultiPost plans and billing when the preflight says the customer cannot publish.
What must be checked for every image URL, not just the array length?
Check that every item is a stable public HTTPS URL available without cookies, browser login or private-network access. MultiPost fetches and re-hosts the images, so one unavailable input can block media preparation for the request.
Use the troubleshooting steps for fixing media_unavailable for public API inputs before retrying a failed source.
Which connected targets support a native slideshow in MultiPost?
MultiPost's slideshow flow supports Instagram, TikTok and Facebook. Validate the target platform and exact handle againstGET /api/v1/accounts instead of assuming every connected network accepts the multi-image format.
For a concrete scheduled payload, see how to schedule a TikTok photo slideshow from public image URLs.
How does MultiPost handle a slideshow after validation passes?
MultiPost re-hosts the external images, keeps their sequence and sends per-target results for immediate or scheduled publishing. Your integration remains responsible for validating the customer's chosen assets, supported targets and current plan before submission.
Frequently asked questions
How many images can a MultiPost slideshow contain?
The Partner API accepts between one and twenty images for a slideshow.
What happens when the request has more than twenty images?
MultiPost returns 400 too_many_images after media preparation finds more than twenty items.
Can the image URLs require login cookies?
No. MultiPost must be able to fetch each URL from its server without an interactive login.
Which targets support the slideshow format?
MultiPost supports native slideshows on Instagram, TikTok and Facebook.
✦ Start free
Validate the sequence before MultiPost prepares the media.
MultiPost keeps the ordered slideshow and returns results for each supported target.