Click on the autogenerated link at the bottom of the endpoint. It is located on the bottom right of the IDE and looks something like this: (https://username.api.stdlib.com/projectName@dev/). Clicking the button will take you to a website with a button that reads "I dare you to click me". If you try to click it, the website will alert you, making it impossible for you to click the button. There is a small chance that you don't get alerted, and instead get ̶r̶i̶c̶k̶r̶o̶l̶l̶e̶d̶ redirected to a surprise website.
let bodyHtml = `
Click Me
`;
return {
statusCode: 200,
headers: {
'Content-Type': 'text/html',
},
body: bodyHtml,
};