What is Full Disk Access on Mac? Why messaging and AI apps ask for it

Full Disk Access is a macOS privacy permission that lets an app open almost everything on your Mac, including data other apps keep private: your Mail, your Messages history, Safari data and Time Machine backups. Messaging and AI apps such as Tera Chat, Beeper and ChatGPT’s Messages plugin ask for it because your iMessage history sits in a protected database on your Mac, and Full Disk Access is the permission that opens it. On 2 October 2026 Apple said it will make granting this access require “very explicit user action”, without giving a date.

This guide explains what the permission really covers, why so many apps want it, which apps ask and for what, how to check, grant and revoke it, and what Apple’s announcement means if you use an iMessage app. Everything here was checked on 20 October 2026 against Apple’s guides for macOS 27 Golden Gate.

What does Full Disk Access let an app do?

It lets an app reach data that macOS normally keeps away from every other app. Apple’s own description in System Settings is that it allows apps to access “all files on your computer, including data from other apps (for example, Mail, Messages, Safari, and Home), data from Time Machine backups, and certain administrative settings for all users on this Mac”.

Normally macOS splits access into narrow permissions: an app asks separately for your Desktop or Documents folder, your contacts, your photos or your calendars, and you approve each one. Full Disk Access skips that system. In Apple’s words, it “largely sidesteps these controls in order to allow backup apps to function properly on the Mac”.

Data on your Mac	Without Full Disk Access	With Full Disk Access
Desktop, Documents and Downloads folders	The app must ask for each folder	Open to the app
Mail, Messages, Safari and Home data	Off-limits to other apps	Open to the app
Time Machine backup data	Off-limits	Open to the app
Certain administrative settings for all users	Off-limits	Open to the app

The key point: there’s no “Full Disk Access for Messages only”. Once you switch it on, the app can open all of it, and you’re trusting it to touch only what it needs.

Why do messaging apps need it for iMessage?

Because the Messages app keeps your history in a protected place. On a Mac, your iMessage conversations (and any SMS or RCS texts forwarded from your iPhone) are stored in a database file called chat.db in the Messages folder of your user Library, with attachments alongside it. That folder is one of the locations macOS protects, so an app that wants to read your history directly needs Full Disk Access.

There are two ways a third-party app can get at iMessage:

1. Read the database directly. This needs Full Disk Access, and it doesn’t touch the Messages window.
2. Drive the Messages app. The app clicks through Messages on your behalf using the Accessibility and Automation permissions. Beeper works this way and warns that the Messages window “may still become briefly visible or flash occasionally.” Even so, since version 4.3.144 (22 September 2026) Beeper Desktop requires Full Disk Access to show iMessage photos and videos on macOS Golden Gate.

Sending is a separate step. Most apps send an iMessage by telling the Messages app to send it, which needs the Automation permission (macOS asks once, the first time). Full Disk Access is about reading.

Which apps ask for Full Disk Access, and why?

Backup tools, iMessage apps and some command-line tools. Here are the common ones and what each uses it for:

App	What it uses Full Disk Access for	Other permissions it asks for
Backup apps such as Carbon Copy Cloner	Copying every file, including protected data; CCC’s own guide walks you through granting it to the app and its helper	None for messaging
ChatGPT’s Apple Messages plugin (Mac app, Work and Codex modes, Apple silicon)	Reading and searching your iMessage, SMS and RCS chats; MacRumors reports it needs Full Disk Access	Contacts (names) and Automation (sending through Messages); it also relies on AppleScript and Accessibility
Beeper Desktop	Showing iMessage photos and videos on macOS Golden Gate (since September 2026)	Accessibility, Contacts, Automation and access to Messages data, to read and drive the Messages app
Tera Chat	Reading your iMessage history on your Mac (optional, only for iMessage)	Automation, to send through Messages; Contacts (optional), to show names instead of numbers. It doesn’t ask for Accessibility
Terminal and command-line tools such as imessage-exporter	Scripts that read your Messages database run with your terminal app’s access	None

A note on Terminal: granting Full Disk Access to Terminal (or another terminal app) applies to whatever you run inside it. That’s convenient for exporting your own messages, and a good reason to switch it off again afterwards.

Is it safe to give an app Full Disk Access?

It’s as safe as the app you give it to. Because macOS can’t narrow the permission, the real question is whether you trust that app with everything on your Mac. Apple’s 2 October statement spells out why it matters for messaging apps in particular: misuse can expose “files, mail, messages, and even browsing history”, and “for communication apps, this can also compromise the privacy of the people users are communicating with.”

Before you switch it on, run through these questions:

1. Do you need the feature that requires it? If you don’t want iMessage in a unified inbox, you don’t need to grant it.
2. Who makes the app, and is it signed and notarized? Download from the developer’s own site or the App Store, and be wary of anything macOS warns you about.
3. What happens to what it reads? Does it stay on your Mac, or is it uploaded to the company’s servers? The privacy policy should say plainly.
4. Does it send anything to AI, and when? AI features send text to a cloud model unless they run on your Mac. Find out which conversations go, and whether any go automatically in the background.
5. What else is it asking for? An app that also wants Accessibility can control your other apps, not just read their data.
6. Will you remember to revoke it? If you stop using the app, take the permission back.

Apple also flagged where this is heading: “As AI agents become increasingly capable and autonomous, the risks associated with this level of access will grow substantially.” Our checklist for letting AI read your messages goes deeper on that side.

How do you check which apps have Full Disk Access?

1. Choose Apple menu → System Settings.
2. Click Privacy & Security in the sidebar (scroll down if you don’t see it).
3. Click Full Disk Access.

Every app in the list has a switch. Any app switched on can open everything described above. If you don’t recognize an app, or no longer use it, switch it off. For the devices signed in to your chat accounts, see how to check if someone is reading your messages.

How do you grant Full Disk Access?

1. Open System Settings → Privacy & Security → Full Disk Access.
2. If the app is already in the list, turn on its switch. If it isn’t, click the Add (+) button below the list, choose the app in your Applications folder, and click Open.
3. Confirm with your Mac password or Touch ID when macOS asks.
4. Quit and reopen the app. Most apps only notice the new access after a restart, and some (Tera Chat included) check for it when they launch.

Apps can’t grant this to themselves, and macOS doesn’t show a pop-up request for it the way it does for your camera or contacts. That’s why apps that need it show their own instructions or a button that opens the right settings pane.

How do you revoke Full Disk Access?

1. Open System Settings → Privacy & Security → Full Disk Access.
2. Turn off the switch next to the app. To take it off the list entirely, select it and click the Remove (−) button.
3. Quit and reopen the app so it picks up the change.

Revoking doesn’t delete anything. The app simply can’t open protected data any more, so features that depend on it stop: an iMessage app that reads the database stops getting new iMessages, and a backup app can’t copy protected files.

What did Apple announce on 2 October 2026?

Apple posted “Updates to Full Disk Access in macOS” on its developer news site. It said some developers “are using Full Disk Access in ways that could put users at risk”, and that “going forward, we will introduce additional controls to ensure that users who genuinely wish to grant an app this extraordinary level of access can only do so with very explicit user action.”

What Apple said	What it hasn’t said yet
Extra controls are coming, so granting takes “very explicit user action”	Which macOS version brings them, or when
The reason: apps exposing files, mail, messages and browsing history without users’ full understanding	What the extra step will look like
Communication apps and AI agents are named as the concern	Whether permissions you’ve already granted will need to be granted again

Nothing changes today: on macOS 27 Golden Gate, the switches in System Settings work as described above. If you use an app that reads iMessage, expect a more deliberate confirmation step at some point, and keep an eye on the app’s release notes when Apple ships the change.

How Tera Chat uses Full Disk Access

Tera Chat needs Full Disk Access only for iMessage, so it can show those conversations next to WhatsApp, Telegram, Instagram and Tinder. It’s optional: skip it and everything else works.

• What it reads: your Messages history on your Mac. Tera Chat stores your messages, contacts and relationship stats in a local database on your Mac; they’re never uploaded to a Tera Chat server.
• How you grant it: Tera Chat can’t switch it on for you. Add it in System Settings → Privacy & Security → Full Disk Access, then quit and reopen Tera Chat.
• Sending: iMessages go out through the Messages app, so macOS asks once for permission to control Messages (Automation).
• Names: iMessage contacts show as numbers or emails unless Tera Chat also has access to your Contacts.
• No Accessibility: Tera Chat reads the database rather than driving the Messages app, so it doesn’t ask for Accessibility access.
• AI: if you set up AI, it sees the conversations it works on, iMessage included, and that text goes to the AI provider you picked.
• Revoking: switch it off any time. Tera Chat pauses iMessage and keeps your other networks working.

The honest caveat is the same as for any app: Full Disk Access technically opens more than Messages, so you’re trusting Tera Chat with it. Our page on whether Tera Chat is safe lists every permission and where your data goes, and the step-by-step iMessage setup guide shows the exact screens. If you’re weighing ChatGPT’s plugin instead, see how ChatGPT works with iMessage on a Mac; for every way to get your chats into one app, see how to combine WhatsApp, iMessage, Telegram and Instagram.

What to do next

Open System Settings → Privacy & Security → Full Disk Access now and look at the list. Switch off anything you don’t recognize or no longer use. Before you grant it to a new app, ask the six questions above, and plan to take it back when you stop using the app.