Creating a custom tool or third party
Go to Tools and Third Parties
Click on Add third party or tool
Click on Create a custom tool or third party
Give your tool a Name, website (optional) and connect it to a similar supported tool (optional)
Connecting it to a similar tool will pull recommendations so you don't need to fill in the information about the tool from scratch. This is completely optional.
Click Create
You will now see the custom tool on your Inventory under the More information needed section. Add any missing information to add it to the inventory.