```js
// /my-addon/register.js

import React from 'react';

import { useParameter } from '@storybook/api';

export const Panel = () => {
  const value = useParameter('parameter-key', 'default value');

  return (
    <div>
      for the currently selected story, the parameter for "parameter-key" is:
      {value}
    </div>
  );
};
```