Sieve is a programming language that can be used to create filters for email on mail server.

pigeonhole can be used with Dovecot. It implements the ManageSieve protocol (specifically RFC 5804).

To manage sieve filters remotely, clients exist for servers implementing the ManageSieve protocol (RFC 5804).

• sieve-connect — Client for the MANAGESIEVE protocol

https://github.com/philpennock/sieve-connect || sieve-connect

• Sieve Script Editor — A graphical client for the ManageSieve protocol for securely managing Sieve Script on a remote IMAP server

https://github.com/thsmi/sieve || sieve-app-bin^AUR

To connect:

$ sieve-connect -s mail.example.com -u user@example.com

Then the help is short and explicit:

> help