How to use WordPress' Lost_Password functions outside of the website?

I basically need to make an API for WordPress that allows simple user edits and such. I've created an API for registering, creating users, retrieving categories, etc...

How can I use WordPress' internal scripts so I can pass it an email ad开发者_StackOverflowdress or username and it will automatically email the user?

// I assume your script is running on the website root folder
include_once("wp-load.php");

// you script start here..