Documentation
https://www.reddit.com/dev/api/
App Configuration
- Visit https://www.reddit.com/prefs/apps/ and create a new web app
 - Provide a name for your web app
 - Provide a redirect uri ending with 
/api/auth/callback/reddit: 

- All other fields are optional
 - Click the "create app" button
 
Options
The Reddit Provider comes with a set of default options:
You can override any of the options to suit your own use case.
Example
import RedditProvider from "next-auth/providers/reddit";
...
providers: [
  RedditProvider({
    clientId: process.env.REDDIT_CLIENT_ID,
    clientSecret: process.env.REDDIT_CLIENT_SECRET
  })
]
...
danger
Reddit requires authorization every time you go through their page.
danger
Only allows one callback URL per Client ID / Client Secret.
tip
This Provider template only has a one hour access token to it and only has the "identity" scope. If you want to get a refresh token as well you must follow this:
providers: [
  RedditProvider({
    clientId: process.env.REDDIT_CLIENT_ID,
    clientSecret: process.env.REDDIT_CLIENT_SECRET,
    authorization: {
      params: {
        duration: 'permanent',
      },
    },
  }),
]