Edit a previously generated spritesheet: re-prompt its underlying animation (edit_mode "prompt"), extend the frame beyond its borders ("outpaint"), or repair a bad loop ("fix_loop"). Pass the `spritesheet_url` you received from `animateSprite`, `transferMotion`, or an earlier edit - it must be a spritesheet you generated within the last 7 days; arbitrary external images are not accepted. A `prompt` is required for edit_mode "prompt", optional for "outpaint", and not accepted for "fix_loop"; optionally add up to 5 reference `images` (URL or base64) to guide the edit. Synchronous until September 10, 2026: the call blocks until the edited spritesheet is rendered and returns the same result shape as animateSprite (spritesheet URL, frame layout, optional GIF or individual frames). Credits are charged only on success, based on the produced duration and never more than the duration you requested. Pass an optional `request_id` to tag the result for later retrieval via `GET /assets/sprites/results`. Requires an API key (user scope). Async is the intended integration pattern: pass `async: true` and the call returns 202 with a job id - poll `GET /assets/jobs/{id}` (`getApiJob` in MCP), honouring poll_after_ms or long-polling with wait=30, until status is succeeded, whose result field is exactly the response documented for this operation. Synchronous responses are deprecated: they remain the default until September 10, 2026, after which requests default to async and return 202 with a job id; set `async: false` explicitly to keep synchronous behavior during and after the transition. Synchronous calls run on the same queue: the response carries an X-Ludo-Job-Id header, and a job still running after 15 minutes comes back as 202 with the job instead of an error. Each account may have up to 50 generations queued or running at once via the API; a request beyond that returns 429 (code PENDING_JOBS_LIMIT).