As per the docs:
Before and after are used to paginate.
The example response:
{"data":
[{
"id":"RandomClip1",
"url":"https://clips.twitch.tv/AwkwardHelplessSalamanderSwiftRage",
"embed_url":"https://clips.twitch.tv/embed?clip=RandomClip1",
"broadcaster_id":"1234",
"broadcaster_name": "JJ",
"creator_id":"123456",
"creator_name": "MrMarshall",
"video_id":"1234567",
"game_id":"33103",
"language":"en",
"title":"random1",
"view_count":10,
"created_at":"2017-11-30T22:34:18Z",
"thumbnail_url":"https://clips-media-assets.twitch.tv/157589949-preview-480x272.jpg"
},
...
]
"pagination": {"cursor": "eyJiIjpudWxsLCJhIjoiIn0"}
}
Returns a pagination -> cursor key.
You pass this in after, to go to the next page, and you pass this to before to go back a page.
Basically the same as saying “give me page 5” but you use the cursor instead.
After:
Cursor for forward pagination: tells the server where to start fetching the next set of results, in a multi-page response. This applies only to queries specifying broadcaster_id or game_id. The cursor value specified here is from the pagination response field of a prior query.
Hope that helps