It depends on the model and the connection

LMCP can read Mail.app through local macOS APIs. That describes where the email tool executes, not where the AI model processes the result. If you use a cloud-backed assistant, requested email contents are returned to that provider under its own terms.

Claude Desktop, Cursor and other desktop clients may use cloud models. ChatGPT and Claude.ai on the web use a network connection, including the optional LMCP Cloud Relay, to request local tool results. The relay carries requests and responses; it does not make cloud inference local.

When can inference stay on-device?

Use a compatible MCP client with an on-device model and only local integrations. Check that the selected model actually runs locally and that optional cloud connectors, remote model fallbacks and relay connections are not part of the workflow. Your email provider may still sync Mail.app separately from LMCP; a local AI configuration does not change that account's existing service.

Connecting Apple Mail

Follow the installation guide and configure Mail.app.
Review the requested macOS permissions and restart your supported MCP client.
Choose the model and connection whose data-handling terms fit your needs.
Start with a non-sensitive test message and request only the information needed.

What happens to a requested message?

Your assistant requests a Mail tool through its configured MCP connection.
The local tool reads the authorized data on your Mac.
The result returns to the assistant. A cloud provider can therefore receive that result.
The assistant generates its answer using the selected local or cloud model.

Sending and changing messages

Preview and confirmation behavior depends on the tool, platform and client. Check the tool reference and inspect the intended recipients and content before authorizing a real action. Do not assume every action has an identical preview dialog.

Privacy and organizational review

Local tool execution alone is not a compliance guarantee. Consider the data being requested, provider terms, account permissions and organizational requirements. See the data-boundary review checklist.

Can AI read email without cloud processing?