We use OpenAI's GPT-3 API to generate summaries. We have explicitly opted out of OpenAI's default behavior of using their APIs to train their models [1].
Our summarization feature is entirely opt-in. So if you're concerned about sharing your emails with OpenAI, you can choose not to use the feature. You can also read our Privacy Policy [2] and Terms of Service [3] to see how your data is used.