| video | VIDEO | | URL of the video to extend. Must be 1.625 s to 60 s long, up to 50 MB, aspect ratio between 0.4 and 2.5. |
| prompt | STRING | | What happens next. Describe the continuation, not the source. |
| enable_prompt_expansion | BOOLEAN | true | Automatically enhance the prompt using the source video to help keep the continuation consistent. May increase processing time. |
| duration | INT | 55–15 | Seconds of new footage to add after the source. The actual duration may be slightly longer. |
| resolution | COMBO | 768P | Output video resolution. |
| aspect_ratio | COMBO | auto | Output aspect ratio. 'auto' follows the source video. Other values crop the video to fit the selected ratio. |
| seed | INT | -1-1–2147483647 | Seed for the continuation. Random when omitted. -1 leaves it to the model. |
| output | COMBO | extended | 'extended' returns the whole source video followed by the new footage. 'continuation' returns only the generated continuation. |
| enable_safety_checker | BOOLEAN | true | Moderate the source video and the prompt. |
| max_cost_usdopt | FLOAT | 20.00–100000 | Safety cap. If the estimated cost of this run is above this many US dollars the node stops BEFORE sending anything to fal. 0 = no cap. |
| reuse_identical_runopt | BOOLEAN | true | If these exact inputs (the settings AND the same pictures/clips/audio) were already paid for and the files are still in output/fal, return them instead of paying again - also after a ComfyUI restart. Turn off for a fresh take with the same settings. |
| extra_jsonopt | STRING | | Advanced: a JSON object merged into the request last, for any fal field this node has no box for. Example: {"seed": 7}. Leave empty normally. |
| max_concurrentopt | INT | 11–32 | How many paid fal calls may run at the same time in one run, across every fal node. 1 (default) = one after another. This node starts its paid part only while fewer than this many fal calls are running. Once any fal node fails, the ones still waiting are not started, so nothing more is billed. |
