Proof of concept automatically add "Recommendation" link to Chatter Posts. Inspired by https://success.salesforce.com/0D53A000036B7Ai

FeedItemTrigger.java

/**
 * For any Chatter post that is not a 'LinkPost' then add a FeedAttachment
 * that links to system to integrate with, such as a third-party system to capture recommendations.
 *
 * https://developer.salesforce.com/docs/atlas.en-us.api.meta/api/sforce_api_objects_feedattachment.htm
 *
 * Inspired by https://success.salesforce.com/0D53A000036B7Ai
 */
trigger FeedItemTrigger on FeedItem (after insert) {

    List<FeedAttachment> feedAttachments = new List<FeedAttachment>();
    
    for ( FeedItem fi : Trigger.new ) {
        if ( fi.type != 'LinkPost' ) {
            feedAttachments.add( new FeedAttachment(
                feedEntityId = fi.id,
                type = 'Link',
                title = 'Recommend',
                value = 'www.your-recommendation-site.com?fid=' + fi.id
            ));
        }
    }
    
    if ( feedAttachments.size() > 0 ) {
        insert feedAttachments;
    }
    
}