Proton Mail Bridge Client

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  Bridge Client  ·  MCP + CLI for Proton Mail, with safety modes

Let Claude Desktop (or Cline, or any MCP client) work with your Proton Mail, with you in control of what it may do. The server can be set to read-only or drafts mode, where nothing is sent, moved or deleted. Sending and deleting can be set to wait for your approval: assisted mode asks for confirmed: true, and PROTONMAIL_APPROVAL=elicit|require makes the server ask you through the client instead of trusting the model. Every change can be recorded in a hash-chained, tamper-evident audit log. The server talks only to Proton Bridge on 127.0.0.1 and keeps its index on your disk; the mail text the AI model reads goes to the model provider unless the model runs locally (see fully local). The threat model says what is and is not covered. The same tools are also available as a full CLI for scripting, cron and piped automation, with no Claude required. A daily brief of new mail and threads waiting on you can be shown as a notification each morning: see scheduled digest.

Know the default: with PROTONMAIL_MODE unset the server runs in full mode (sending allowed, no approval), but a new setup-claude-desktop install writes PROTONMAIL_MODE=drafts (Claude can read and write drafts, not send; moves and permanent delete are off in its action list). Re-running setup on an existing install keeps its mode. To allow sending set PROTONMAIL_MODE=full; for read-only use read-only (see Safety controls). Approval by elicitation depends on the client supporting it; only require fails closed.

Using Proton Drive too? See proton-drive-mcp, the companion MCP server and CLI for Proton Drive (upload, download, share and manage your encrypted files from Claude). Run both side by side to handle mail and files in one conversation, for example save an attachment from here, then upload it to Drive. More in Related projects.

Battle-tested at scale (v2.0.0): full mailbox backfill validated end-to-end against a rea

... View full README on GitHub