Can ChatGPT Read Your Email on a Mac?

Checked November 6, 2026

Yes, through Codex in the ChatGPT desktop app. Codex can connect to MCP servers on your Mac, so it can use the one built into Postage to search and read every IMAP account you've added: Gmail, iCloud, Fastmail, Yahoo or your own domain. ChatGPT on the web can't reach it, because OpenAI's docs say ChatGPT web uses remote MCP tools and Postage's server stays on your Mac.

Where it works

Where you use it	Can it reach Postage?	Why
Codex in the ChatGPT desktop app	Yes	Reads MCP servers from ~/.codex/config.toml
Codex CLI	Yes	Shares that same config file
Codex IDE extension	Yes	Shares that same config file
ChatGPT on the web	No	Uses remote MCP tools; Postage listens only on 127.0.0.1

OpenAI facts from its Model Context Protocol docs at learn.chatgpt.com/docs/extend/mcp, checked 2026-11-06.

In the desktop app, choose Codex rather than ChatGPT's Chat or Work modes: OpenAI documents this MCP configuration for Codex.

What Codex can read

Every folder of every account in Postage, with search on the mail server.
Whole threads and messages as plain text, with the sender's words marked as untrusted content.
The text of PDF, text, HTML, CSV, JSON and XML attachments.
Unread counts per folder, and a marker on newsletters and machine-sent mail.

Outlook.com, Hotmail and Microsoft 365 accounts can't be added to Postage yet, because Microsoft turned off password sign-in for mail apps and Postage doesn't support Microsoft's own sign-in. Codex can't reach those mailboxes through Postage.

How to turn it on

Add your accounts to Postage.
In Settings > Agents, turn on Let agents connect to Postage.
Under Codex, press Add Postage to Codex and pick your ~/.codex/config.toml. Postage saves a backup first.
Restart Codex and ask it to list your Postage accounts.

The config entry and the manual route are in Use Codex and the ChatGPT desktop app with your email.

What it can do beyond reading

Codex starts at Read only, so it can look and change nothing. Organize and draft adds archiving, moving, flagging and saving drafts. Full adds moving mail to Trash. A message Codex writes opens in a Postage compose window, and it goes out only when you press Send.

Questions

Can ChatGPT read my Gmail through Postage?

Yes, through Codex. Add Gmail to Postage with a Google app password, and Codex sees it with your other accounts.

Can ChatGPT read my email on the web?

Not through Postage. Its server listens only on your Mac, and ChatGPT on the web uses remote MCP tools.

Does my mail go to OpenAI?

Only what Codex reads during a conversation you're having, under OpenAI's terms. Postage has no servers of its own, and it talks to your mail provider directly from your Mac.

Can ChatGPT send email through Postage?

No. Codex can write the message, and only you can press Send.

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