The available Twitch OAuth scopes listed in different formats - (Source: https://dev.twitch.tv/docs/authentication/#scopes)

Plain.json

[
    "user_read",
    "user_blocks_edit",
    "user_blocks_read",
    "user_follows_edit",
    "channel_read",
    "channel_editor",
    "channel_commercial",
    "channel_stream",
    "channel_subscriptions",
    "user_subscriptions",
    "channel_check_subscription",
    "chat_login",
    "channel_feed_read",
    "channel_feed_edit",
    "collections_edit",
    "communities_edit",
    "communities_moderate",
    "viewing_activity_read"
]

Plain.php

<?php
$scopes = [
    'user_read',
    'user_blocks_edit',
    'user_blocks_read',
    'user_follows_edit',
    'channel_read',
    'channel_editor',
    'channel_commercial',
    'channel_stream',
    'channel_subscriptions',
    'user_subscriptions',
    'channel_check_subscription',
    'chat_login',
    'channel_feed_read',
    'channel_feed_edit',
    'collections_edit',
    'communities_edit',
    'communities_moderate',
    'viewing_activity_read'
];

WithDescriptions.json

{
    "user_read": "Read access to non-public user information, such as email address.",
    "user_blocks_edit": "Ability to ignore or unignore on behalf of a user.",
    "user_blocks_read": "Read access to a user's list of ignored users.",
    "user_follows_edit": "Access to manage a user's followed channels.",
    "channel_read": "Read access to non-public channel information, including email address and stream key.",
    "channel_editor": "Write access to channel metadata (game, status, etc).",
    "channel_commercial": "Access to trigger commercials on channel.",
    "channel_stream": "Ability to reset a channel's stream key.",
    "channel_subscriptions": "Read access to all subscribers to your channel.",
    "user_subscriptions": "Read access to subscriptions of a user.",
    "channel_check_subscription": "Read access to check if a user is subscribed to your channel.",
    "chat_login": "Ability to log into chat and send messages.",
    "channel_feed_read": "Ability to view to a channel feed.",
    "channel_feed_edit": "Ability to add posts and reactions to a channel feed.",
    "collections_edit": "Manage a user’s collections (of videos).",
    "communities_edit": "Manage a user’s communities.",
    "communities_moderate": "Manage community moderators.",
    "viewing_activity_read": "Turn on Viewer Heartbeat Service ability to record user data."
}

WithDescriptions.php

<?php
$scopes = [
    'user_read' => "Read access to non-public user information, such as email address.",
    'user_blocks_edit' => "Ability to ignore or unignore on behalf of a user.",
    'user_blocks_read' => "Read access to a user's list of ignored users.",
    'user_follows_edit' => "Access to manage a user's followed channels.",
    'channel_read' => "Read access to non-public channel information, including email address and stream key.",
    'channel_editor' => "Write access to channel metadata (game, status, etc).",
    'channel_commercial' => "Access to trigger commercials on channel.",
    'channel_stream' => "Ability to reset a channel's stream key.",
    'channel_subscriptions' => "Read access to all subscribers to your channel.",
    'user_subscriptions' => "Read access to subscriptions of a user.",
    'channel_check_subscription' => "Read access to check if a user is subscribed to your channel.",
    'chat_login' => "Ability to log into chat and send messages.",
    'channel_feed_read' => "Ability to view to a channel feed.",
    'channel_feed_edit' => "Ability to add posts and reactions to a channel feed.",
    'collections_edit' => "Manage a user’s collections (of videos).",
    'communities_edit' => "Manage a user’s communities.",
    'communities_moderate' => "Manage community moderators.",
    'viewing_activity_read' => "Turn on Viewer Heartbeat Service ability to record user data."
];