How to make an Oclif command the default command when using explicit command strategy?

I'm building a CLI using Oclif v4 with TypeScript and tsup for bundling. I want my main command to run by default, without requiring the user to type it as a subcommand.

Currently, my oclif configuration in package.json looks like this:

"oclif": {
  "bin": "my-cli",
  "commands": {
    "strategy": "explicit",
    "target": "./dist/index.js",
    "identifier": "COMMANDS"
  },
  "dirname": "my-cli",
  "topicSeparator": " "
}

And in src/index.ts:

import { Command, Flags } from "@oclif/core";

class MyCommand extends Command {
  static override id = ".";
  static override description = "Main command description";

  static override flags = {
    help: Flags.help({ char: "h" })
  };

  async run() {
    this.log("Running main command");
  }
}

export const COMMANDS = { MyCommand };

With this setup, the CLI works when I run:

my-cli MyCommand --help

But I want the command to run by default when executing:

my-cli --help

I tried changing the identifier in the oclif config to "default" and also exporting the command as default:

export default MyCommand;

But then my-cli --help only shows:

USAGE $ my-cli [COMMAND]

and running my-cli MyCommand --help fails with:

Error: Command MyCommand not found

How can I configure Oclif so that my main command is the default command, while still using the explicit command strategy?