Generate (`runway_generate`): Required prompt (≤1800 characters); optional one reference image (JPG/PNG, max 10MB). Duration 5s or 10s; 720p/1080p (10s clips are 720p only). Aspect ratio 16:9, 4:3, 1:1, 3:4, 9:16 when no image. RULE pricing by duration + quality.
Extend (`runway_extend`): Task ID from completed Runway Generate jobs + prompt (≤1000). Output 720p/1080p; per-run credits.
Aleph (`runway_aleph`): Uploaded video URL + prompt; optional reference image, aspect ratio, seed, watermark (≤20 chars). Output length inherits source; per-run credits.

