A text field contains free-form text.

Packages

As JSON from packages:

{
	"subject": "I need some help with this software"
}

To enter multiple lines of text, use \n control characters.

{
	"subject": "Line 1\nLine 2\n"
}

Records API

In PUT or POST requests from the API the text should be URL encoded.

&fields[subject]=I+need+help+with+this+software

To enter multiple lines of text, encode \n as %0A:

&fields[subject]=Line+1%0ALine+2