Animate a static sprite into a spritesheet driven by a motion text prompt (image-to-spritesheet): supply an initial_image (URL or base64) plus a motion_prompt like "walking" or "attack slash", and optionally a final_image to interpolate between a start and end frame. Describe the motion exactly and unambiguously, but do not over-describe it: an action the model already knows is one phrase, not a sequence of steps, and the character, art style, background and camera come from the image, not the prompt. For animations driven by up to three keyframes (including a middle frame), use animateSpriteKeyframes instead. The job result is a single sprite result: `spritesheet_url` (the sheet image), `video_url` (an mp4 of the animation - pass it as `video` to transferMotion or as `spritesheet_video_url` to createSpriteAudio; editSpritesheet takes `spritesheet_url`), `num_frames`/`num_cols`/`num_rows` (the grid layout), and, when requested, `gif_url`, `individual_frame_urls` and `spritesheet_with_background_url`. The hydra and hydra-plus models also return `audio_url`, a sound effect for the animation - there is no need to call createSpriteAudio afterwards; forge and forge-pixel produce no audio. The chosen model must support sprite animation and the duration must be valid for it; incompatible model/duration combinations return HTTP 400. Credits are held for the duration you requested when the job is accepted; the final charge is rate × seconds of video generated (legacy models keep their minimum charge), never more than for the duration you requested, and the difference (or everything, if the job fails or is cancelled) is refunded. The returned sheet is then trimmed to its best loop and can run slightly shorter than the video; that trim is not deducted. Choosing a tool: animateSprite (this one) when you can describe the motion in text; transferMotion when you want an exact motion copied from a reference video or one of the named presets from listAnimationPresets (e.g. a standard walk or attack cycle); generatePose first when the source image is not yet in the pose the animation should start from. Omit `model` to run on hydra (the default) - see the `model` field for the per-model rates. Pass an optional request_id to tag the result so you can locate it later via listGenerations (type spritesheet). Async generation job: returns `{id, status}` - poll `getApiJob` (job and credit contract: see the server instructions).
Credits: credits/s × seconds, per model: Hydra 3/s (shortest duration 3s, so 9 credits minimum), Hydra+ 4/s (shortest duration 3s, so 12 credits minimum), Forge 1.5/s, Forge Pixel 1.5/s, Blitz 1.9/s (min charge 4 credits) [LEGACY], Eagle 2.6/s (min charge 4 credits) [LEGACY], Eagle with Audio 3.1/s (min charge 4 credits) [LEGACY]; [LEGACY] models are scheduled for removal - do not use them for new work; see this endpoint's full pricing table in the API docs.
