# VendorModelRule - [OpenAPI fragment](https://www.lusid.com/docs/api/lusid/schemas/VendorModelRule.json) - [Rendered page](https://www.lusid.com/docs/api/lusid/schemas/VendorModelRule) A rule that identifies the set of preferences to be used for a given library, model and instrument type. There can be many such rules, though only the first found for a given combination would be used. ## Referenced schemas - [ModelOptions](https://www.lusid.com/docs/api/lusid/schemas/ModelOptions.txt) - [AddressKeyFilter](https://www.lusid.com/docs/api/lusid/schemas/AddressKeyFilter.txt) ## Used by schemas - [PricingContext](https://www.lusid.com/docs/api/lusid/schemas/PricingContext.txt) [< Schemas](https://www.lusid.com/docs/api/lusid/schemas/llms.txt)