> For the complete documentation index, see [llms.txt](https://docs.catanatron.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.catanatron.com/advanced/editor.md).

# Creating Custom Bots

Implement your own bots by creating a file (e.g. `myplayers.py`) with some `Player` implementations, and registering it for CLI usage:

```python
from catanatron import Player
from catanatron.cli import register_cli_player

class FooPlayer(Player):
    def decide(self, game, playable_actions):
        """Should return one of the playable_actions.

        Args:
            game (Game): complete game state. read-only.
            playable_actions (Iterable[Action]): options to choose from
        Return:
            action (Action): Chosen element of playable_actions
        """
        # ===== YOUR CODE HERE =====
        # As an example we simply return the first action:
        return playable_actions[0]  # type: ignore
        # ===== END YOUR CODE =====

register_cli_player("FOO", FooPlayer)
```

Run it by passing the source code to `catanatron-play`:

```bash
catanatron-play --code=myplayers.py --players=R,R,R,FOO --num=10
```


---

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