> For the complete documentation index, see [llms.txt](https://docs.yarnspinner.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.yarnspinner.dev/2.5/using-yarnspinner-with-rust/creating-commands-functions.md).

# Custom Commands and Functions

* You can define your own [commands](/2.5/using-yarnspinner-with-rust/creating-commands-functions/creating-commands.md), which allow the scripts you write in Yarn Spinner to control parts of the game that you've built.
* [Functions](/2.5/using-yarnspinner-with-rust/creating-commands-functions/creating-functions.md) are units of code that Yarn scripts can call to receive a value. In addition to the [built-in functions](/2.5/getting-started/writing-in-yarn/functions.md#built-in-functions) that come with Yarn Spinner, you can create your own.