It will let users quickly paste generated responses into a draft, like the Insert button in the Help me write tool.

The Gemini panel unlocks a host of useful AI features in the Gmail app. You can use it to summarize email threads, find information from old emails, and view or add events in Google Calendar. It can also help you draft responses. However, unlike the Help me write tool on the compose screen, the Gemini panel currently doesn't offer the option to insert generated replies directly into a draft. You have to copy and paste the response manually, but Google could change that soon.