# Custom

Functions in the **Custom** category of the Studio `fx` menu cover Mindflow-native helpers for conditions, string
work, IDs, and document conversion.

Start with conditions and strings:

- [Compare](./compare/) — combine terms with And/Or to drive condition steps.
- [Assert](./assert/) — fail the step when a check is not true.
- [Concatenate](./concatenate/) — join strings.
- [UUID V4](./uuid-v4/) — generate a random UUID.

Common conversion and extraction:

- [CSV to JSON](./csv-to-json/) / [XML to JSON](./xml-to-json/) / [MSG to JSON](./msg-to-json/) — turn structured files
  into JSON.
- [XPath](./xpath/) — select values from XML.
- [Extract Email Addresses](./extract-email-addresses/) — list emails found in text.

Open a function page from the sidebar for parameters, returned values, and examples. The transform functions overview
also summarizes this category.