The guide explains how to integrate Moesif behavioral emails with Sendgrid to automatically notify customers based on their API usage, addressing technical issues like rate limits or deprecated APIs, and triggering business events. It outlines the process of obtaining SMTP credentials from Sendgrid, configuring the Moesif email server, and testing the setup by sending an example email. This integration enables effective communication with API consumers, ensuring they are informed of crucial updates, while Sendgrid mitigates common email delivery challenges. The article emphasizes the ease of setup and the benefits of combining Moesif's service with Sendgrid to enhance API platform success.