Welcome to the Pixeldrain API documentation.
The methods for uploading and retrieving files don't require an
API key. The methods for creating and retrieving lists also
don't require an API key. All methods which delete or modify a
resource do require an API key.
Though API keys have not been implemented yet, so you can't use
those methods yet.
Some JSON responses include fields which end in "_href" (some people don't know this, but "href" stands for "Hypertext Reference", the more you know). These point to different places in the API, which you can retrieve with a GET request. The path is to be appended to the API URL, so "/file/someid/thumbnail" becomes "{{apiUrl}}/file/someid/thumbnail".
The base URL for the API is "{{apiUrl}}", all paths below are relative to that URL.