> ## Documentation Index
> Fetch the complete documentation index at: https://openrouter.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# PricingSource

Who bills the engine's calls beyond the model's tokens: `openrouter` (the `pricing` rows, from the caller's credits), `provider` (a per-call tool fee from the model's provider on the inference call, at its own rates), `byok` (the engine's vendor, against the caller's own key), or `none` (no charge)

## Example Usage

```python theme={null}
from openrouter.components import PricingSource

# Open enum: unrecognized values are captured as UnrecognizedStr
value: PricingSource = "openrouter"
```

## Values

This is an open enum. Unrecognized values will not fail type checks.

* `"openrouter"`
* `"provider"`
* `"byok"`
* `"none"`