To create a plain-text note, POST an activity to the user's feed (/api/user/fred/feed) like so:

json { "verb": "post" "object": { "objectType": "note", "content": "Hello, World!" } }

The content can be of any length. It can include HTML5.

json { "verb": "post" "object": { "objectType": "note", "content": "Hello, World!" } }

"Dangerous" parts of the HTML will be scrubbed. This includes any JavaScript.

json { "verb": "post" "object": { "objectType": "note", "content": "Hello, World! <script>alert('gotcha!')</script>" } }