A feed (Atom, RSS etc) provides updated content to the subscribers and brings more traffic to your site. But, if the feed contains full article instead of summary, the subscriber may not visit your site as he/she can see the full content in the feed itself. So, check your feed and if it is showing full article, you have to change the settings in wordpress.
Follow below steps in wordpress to show only the summary of each article in the feed.
- Login to your wordpress site
- Goto Settings -> Reading
- Select “Summary” setting like shown in below figure
- Click on Save changes button
Ping and check your feed.