Proton Mail

Proton Mail (via Proton Bridge)

Read and search Proton Mail from the command line through the locally running Proton Bridge app, which exposes a standard IMAP server (127.0.0.1:1143) over STARTTLS. All work goes through one helper: scripts/proton_mail.py.

This skill is read-only by design: it lists, searches, and reads messages. It does not send, delete, move, or flag mail.

Prerequisites (check before any operation)

1. Proton Bridge must be running. Quick check:

   pgrep -af protonmail-bridge
   

   If nothing prints, tell the user to start it (it is a desktop/tray app):

   protonmail-bridge --no-window &
   

2. Credentials file ~/.proton-imap must exist with KEY=VALUE lines:

   PROTON_IMAP_USER=you@proton.me
   PROTON_IMAP_PASS=<bridge-generated password>
   PROTON_IMAP_HOST=127.0.0.1
   PROTON_IMAP_PORT=1143
   

   The password is the bridge-specific password shown in the Proton Bridge app under "Mailbox details", NOT the Proton account password. The file should be chmod 600. If it is missing, ask the user for the bridge username and password (or have them run protonmail-bridge --cli then info), then write the file yourself with umask 077.

Usage

Run the helper with python3 (stdlib only, no deps):

python3 scripts/proton_mail.py <subcommand> [options]

Resolve the script path relative to this SKILL.md if the client exposes the skill directory; otherwise use the absolute path ~/Documents/Project/AI_Project/skills/proton-mail/scripts/proton_mail.py.

folders

List every mailbox with message and unread counts. Good first call to discover folder names (Proton labels appear as IMAP folders, e.g. Folders/..., Labels/...).

python3 scripts/proton_mail.py folders

list

Recent messages, newest first. Default 15 from INBOX.

python3 scripts/proton_mail.py list -n 20 -f INBOX

Each block shows a ● marker for unread, the date, From, Subject, and a [uid N] token. Pass that UID to read.

unread

Only unseen messages (default 30).

python3 scripts/proton_mail.py unread -n 50

search

IMAP server-side search. Combine filters freely; with no filter it lists all.

python3 scripts/proton_mail.py search --from kaist.ac.kr
python3 scripts/proton_mail.py search --subject invoice --since 01-Jun-2026
python3 scripts/proton_mail.py search --text "poster" --unread -n 10

• --from / --subject / --text are substring matches.
• --since DD-Mon-YYYY (e.g. 01-Jun-2026) means on/after that date.
• --unread restricts to unseen.
• -f selects a folder (default INBOX); use -f "All Mail" to search everything.

read

Full content of one message by UID. Prefers the text/plain part, falls back to HTML. Reading is non-destructive (does NOT mark the message as seen).

python3 scripts/proton_mail.py read 9253
python3 scripts/proton_mail.py read 9253 --headers   # headers only
python3 scripts/proton_mail.py read 9253 -f Sent
python3 scripts/proton_mail.py read 9253 --raw > msg.eml   # raw RFC822

UIDs are stable within a folder, but differ across folders. Always pair a UID with the folder it came from.

Notes & gotchas

• The bridge cert is self-signed for localhost; the helper disables cert verification deliberately (connection never leaves 127.0.0.1).
• INBOX can hold thousands of messages; always bound listings with -n.
• "Connection refused" / "cannot reach IMAP" means the bridge is not running.
• "IMAP login failed" means the bridge password in ~/.proton-imap is stale. Bridge rotates it if the user re-adds the account; refresh from the app.
• This skill is read/search only; it does not send, delete, move, or flag mail.