What are best practices for the description (RSS) or summary (Atom) field in a SmartFormat feed?

A description/summary should be an editorially focused, concise block of text that helps the reader further understand the story. It works as an addition to a headline and thumbnail. It should be written in complete sentences.

Background:

The three core elements of story presentation in most forms of news aggregation are:

  1. The headline
  2. The photo
  3. The description/summary

The description/summary can be the same as what appear in the meta description of a story's source HTML. We ask that they are included in the <description> (RSS) or <summary> (Atom) element of a SmartFormat feed item (for examples, please see the SmartFormat Specification).

Some suggestions:

Do: Be concise. It seems like 150 characters is a good maximum to aim for. Short and snappy works!

Do not: Run long without tact. A meandering description/summary that runs long can be confusing.

Do: Write in a full sentence or full sentences

Do not: Write in headline format

Do: Build on or supplement the headline

Do not: Repeat the headline verbatim