Connect in Apex Features | Apex Developer Guide

Working with Action Links
An action link is a button on a feed element. Clicking an action link can take a user to a Web page, initiate a file download, or invoke an API call to Salesforce or to an external server. An action link includes a URL and an HTTP method, and can include a request body and header information, such as an OAuth token for authentication. Use action links to integrate Salesforce and third-party services into the feed so that users can drive productivity and accelerate innovation.

Working with Feeds and Feed Elements
The Chatter feed is a container of feed elements. The abstract class ConnectApi.FeedElement is a parent class to the ConnectApi.FeedItem class, representing feed posts, and the ConnectApi.GenericFeedElement class, representing bundles and recommendations in the feed.

Accessing ConnectApi Data in Experience Cloud Sites
Many ConnectApi methods work within the context of a single Experience Cloud site.

Methods Available to Experience Cloud Guest Users
If your Experience Cloud site allows access without logging in, guest users have access to many Apex methods. These methods return information the guest user has access to.

Supported Validations for DBT Segments
When creating or updating a segment, the ConnectApi.CdpSegmentInput class is subject to some SQL validations.