Touch Portal does not provide any SDK but our awesome community has done so for our API. The list below shows SDKs developed by users in the community. Check them out if you want to start on building a plug-in!
Christophe made a very nice SDK for Java. Using this will remove all the hassle of setting up a plug-in and allows you to start building the actual integration right away. Checkout the Java SDK at ChristopheCVB's GitHub page
Our community member Spdermn02 has made an SDK for Node.JS. It is a good starting point to start developing your plug-in for Touch Portal in Node.JS https://www.npmjs.com/package/touchportal-api
Our community member ! xXKiller_BOSSXx has made an SDK for Python. It is a good starting point for your Touch Portal plug-in in Python, check it out at https://pypi.org/project/TouchPortal-API/
Our community member oddbear has made an SDK for C#. It is a good starting point for your Touch Portal plug-in in C#, check it out at https://www.nuget.org/packages/TouchPortalSDK/
There is currently no SDK available for this language/framework.