# tinker_cookbook.preference.ComparisonRenderer

## *class* [**tinker_cookbook.preference.ComparisonRenderer**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/preference/types.py#L95)()

Abstract renderer for converting Comparisons to model inputs for preference training.

Subclasses must implement `build_generation_prompt`, `to_model_input_weights`, and the `tokenizer` property.

### [**build_generation_prompt**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/preference/types.py#L102)(*comparison*)

Build a model input for generating a preference label.

**Parameters:**

- [**comparison**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/preference/types.py#L102) (*[Comparison](https://tinker-docs.thinkingmachines.ai/cookbook/api-reference/preference/comparison/index.md)*) – The comparison to render as a prompt.

**Returns:** *types.[ModelInput](https://tinker-docs.thinkingmachines.ai/tinker/api-reference/types/modelinput/index.md)* – Token-level model input ready for sampling.

### [**to_model_input_weights**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/preference/types.py#L113)(*labeled_comparison*)

Convert a labeled comparison to model input and per-token loss weights.

**Parameters:**

- [**labeled_comparison**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/preference/types.py#L114) (*[LabeledComparison](https://tinker-docs.thinkingmachines.ai/cookbook/api-reference/preference/labeledcomparison/index.md)*) – A comparison annotated with a preference label.

**Returns:** A tuple of (model_input, weights) for training.

### *property* [**tokenizer**](https://github.com/thinking-machines-lab/tinker-cookbook/blob/main/tinker_cookbook/preference/types.py#L127)

The tokenizer associated with this renderer.

**Returns:** *Tokenizer* – The tokenizer instance.

## Referenced by

- [tinker_cookbook.preference.ComparisonRendererFromChatRenderer](https://tinker-docs.thinkingmachines.ai/cookbook/api-reference/preference/comparisonrendererfromchatrenderer/index.md)