This wouldn't be an integration in Missive, but would be a plugin added to Codex. The idea would be like the Gmail and Outlook plugin that exists in Codex. This would allow Codex to read, summarize, draft, organize, triage.

I think this would be a powerful combination if Codex could have access to Missive and read personal inbox, team inboxes, and chats. It could give Missive/Codex users very powerful insights and action items.