# Discount engines At the moment the following types of discount engines are available (more to come): * [Talon.One](/core-api-reference/talon_one_accounts.md) — leverage our out-of-the-box integration with [Talon.One](https://www.talon.one/). {% hint style="info" %} This is an **immutable API**, meaning that create, update, and delete operations are not allowed on this endpoint. You can only fetch a list of discount engines or a single discount engine object. For the full set of available CRUD actions to the specific discount engine type endpoints. {% endhint %} --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.commercelayer.io/core-api-reference/discount_engines.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.