How do you properly encode a value to be part of an HTTP POST body? or What’s the best way to encode

Honestly, it depends on the content-type header. If it's `application/x-www-form-urlencoded`, URL encode it. If it's `application/json`, stringify it.

Big gotcha: some APIs freak out if you mix them up. Like, sending URL-encoded stuff in a JSON body. Always check the API docs!

Tools like https://www.url-encode-decode.com/ can help you test encoding manually.