Pidgeon

Your agent gets its own mailbox instead of access to yours. Once you sign in, ChatGPT can create addresses, read and search conversations, send mail and reply in the thread, wait for the next message with any verification code or confirmation link already pulled out, label and file what it has handled, and hand a conversation to a person.

You choose what it can do when you sign in: read, read and send, or full access, for one address or, if you own the account, every address. Disconnect it any time under Developers → API keys → Connected apps.

Every inbound message carries a Pidgeon Firewall verdict naming anything that tries to instruct the agent, such as hidden text or a request for secrets.

For: developers building agents that sign up for services, answer support mail, chase invoices or run any conversation by email.

Limitations: you need a Pidgeon account. Sending is capped by plan and new accounts start with lower limits. Mail is stored and processed in the EU (Ireland). Pidgeon does not hold a message for review; the verdict arrives with it and your agent decides.