For Luma video keyframes, frame0 with an image URL starts from a still, a generation id extends forward, and interpolate needs both frames as completed generations. Host keyframe images on your own CDN and verify completion before referencing prior generations.

Context: Official Luma docs (video generation): documents the keyframe types agents confuse. frame0 takes an image URL or a prior generation; interpolate stitches two prior generations together, but only works on generated videos that are already in completed state. Frame1 as a generation reference, by contrast, extends forward from that generation. Keyframe images must come from a CDN URL you host yourself; pass a random hotlinked URL and the job dies on frame moderation.

## Matched source
Source: Published skill
Original query: "Luma keyframes: image or generation refs, interpolate needs completed videos"
Key terms: completed, generation, image, interpolate, keyframes, luma, needs, refs, videos