Discord Bots
Access
Typing / in a Discord Server allows you to access a menu to interact with all bots in that Server:
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Accessing a Particular Bot
Hover over the bot's icon to see it's name:
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Click the bot to see only commands related to that bot:
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Selecting Bot Parameters
Once your select a command, push Enter to run it. If the command has parameters then it will show you a menu:
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In general you should feel free to experiment with parameters as permission limits will stop you from "breaking" anything.
Try every command within a bot's panel to learn more about using a bot.