That's right, Capes API is live! For now we'll be manually verifying all the developers to help control the amount of calls made to our servers to help us determine our future updates.
Capes API is a product created by Halfpetal and the WiZARDHAX crew for Minecraft hacked client or Forge mod developers.
The issue we've seen is that every client has a cape, but you have to be on that client to see that cape. We're hoping to help resolve that issue by giving developers a central location to store their cape data along with managing the users that use their capes.
It also gives your users the ability to log in and select which cape they want to use with their Mojang account.