There are 2 repositories under mastodon-apis topic.
MastodonKit is a Swift Framework that wraps Mastodon's API
Mastodon API Client Library
A Mastodon API client written in Swift for iOS, iPadOS and macOS.
Useful tools for Mastodon users !
Javascript Mastodon API for Web Browsers with streaming support
sample code of "Mastodon Book" http://nextpublishing.jp/book/8776.html
a mastodon self-bot coded in Python