TextGenerateLTX2Prompt - ComfyUI Built-in Node Documentation

The TextGenerateLTX2Prompt node expands a short user prompt into a detailed, audio-visual description suitable for generating video with the LTX-2 series of video models. It automatically adds task-specific system instructions, sends the formatted prompt to a language model, and returns the enhanced text. When an optional reference image is supplied, the node switches to image-to-video mode and expands the prompt starting from that image’s content.

Inputs

Parameter	Description	Data Type	Required	Range
`clip`	The CLIP model used for text encoding. The node checks the model’s tokenizer name to select the matching instructions: Gemma 4 based models use the LTX-2.4 format, while other models use the LTX-2 (Gemma 3) format.	CLIP	Yes
`prompt`	The raw text input describing the scene or concept to be expanded into a detailed video generation prompt.	STRING	Yes
`max_length`	The maximum number of tokens the language model is allowed to generate.	INT	Yes
`sampling_mode`	The sampling strategy used to select the next token during text generation.	COMBO	Yes	`"greedy"` `"top_k"` `"top_p"` `"temperature"`
`image`	An optional input image used as the first frame of the video. When provided, the node switches to image-to-video mode and uses a system prompt that expands the user prompt based on the image’s content.	IMAGE	No
`thinking`	When enabled, the model is instructed to reason before answering. Any reasoning block is removed from the returned output (default: False).	BOOLEAN	No
`use_default_template`	When enabled, the node uses the default chat template for formatting (default: True).	BOOLEAN	No
`video`	An optional video input that can be used as additional context for generation.	VIDEO	No
`audio`	An optional audio input that can be used as additional context for generation.	AUDIO	No

Note: The behavior of the node changes based on its inputs:

If an image is provided, the generated prompt is formatted for an image-to-video task using a system prompt that describes how to expand the prompt based on the image’s content. If no image is provided, the formatting is for a text-to-video task using a system prompt that expands the prompt into a detailed video generation description.
If the CLIP tokenizer’s name contains “gemma4”, the node uses the LTX-2.4 system prompts and the Gemma 4 chat format. Otherwise, it uses the LTX-2 (Gemma 3) system prompts and chat format.
If the language model produces no usable text after removing reasoning blocks, the node returns the original prompt instead.

Outputs

Output Name	Description	Data Type
`output`	The enhanced video-generation prompt produced by the language model, with any reasoning block removed. If the result is empty, the original user prompt is returned.	STRING

This documentation was AI-generated. If you find any errors or have suggestions for improvement, please feel free to contribute! Edit on GitHub

Source fingerprint (SHA-256): 8f524ea60a247217dde8a1edaf7a689e253ae05acc9eb52ad47b91e879dba1df

​Inputs

​Outputs

Inputs

Outputs