Discord bot TypeError: function missing required parameter 'ctx'

Other Questions Discord bot
1

I’m working on a Discord bot and keep getting a TypeError about a missing ‘ctx’ parameter. Here’s my current code:

import discord
import os
from dotenv import load_dotenv
from discord.ext import commands
import logging


class BotHandler:
    def __init__(self) -> None:
        self.permissions = discord.Intents.all()
        self.permissions.messages = True
        self.permissions.message_content = True
        self.permissions.guilds = True
        self.permissions.members = True
        self.permissions.presences = True
        self.client = commands.Bot(command_prefix='!', intents=self.permissions)

    async def on_ready(self):
        print("Bot is online.")
    
    @commands.command()
    async def greet(self, context):
        await context.channel.send('Hi there!')
        print("GREETING SENT!")


if __name__ == '__main__':
    load_dotenv()

    BOT_TOKEN = os.getenv('BOT_TOKEN')

    logging.basicConfig(level=logging.DEBUG)
    my_bot = BotHandler()
    my_bot.client.add_command(my_bot.greet)

    my_bot.client.run(BOT_TOKEN)

The error traceback shows:

ERROR:discord.ext.commands.bot:Ignoring exception in command greet
Traceback (most recent call last):
  File "/lib/python3.12/site-packages/discord/ext/commands/core.py", line 235, in wrapped
    ret = await coro(*args, **kwargs)
  TypeError: BotHandler.greet() missing 1 required positional argument: 'context'

What’s causing this issue and how can I resolve it?

2

The problem is how you’re registering the command. When you use my_bot.client.add_command(my_bot.greet), discord.py doesn’t know the command belongs to your BotHandler instance, so it can’t pass the self parameter automatically. I hit this same issue when I started using custom classes for bots. Easiest fix? Make your BotHandler inherit from commands.Bot instead of wrapping it:

class BotHandler(commands.Bot):
    def __init__(self) -> None:
        permissions = discord.Intents.all()
        permissions.messages = True
        permissions.message_content = True
        super().__init__(command_prefix='!', intents=permissions)
    
    @commands.command()
    async def greet(self, ctx):
        await ctx.send('Hi there!')
        print("GREETING SENT!")

Then just create and run it: my_bot = BotHandler() and my_bot.run(BOT_TOKEN). Now the command decorator binds properly to your class and discord.py handles the context parameter like it should.

3

You could also use functools.partial to bind the self parameter when adding the command. Just do from functools import partial then my_bot.client.add_command(commands.Command(my_bot.greet, name='greet')) but Jack’s inheritance approach is way cleaner and less hacky