Usage: pgp-hook
pattern keyid
When encrypting messages with PGP, you may want to associate a certain PGP key with a given e-mail address automatically, either because the recipient's public key can't be deduced from the destination address, or because, for some reasons, you need to override the key Mutt would normally use. The pgp-hook command provides a method by which you can specify the ID of the public key to be used when encrypting messages to a certain recipient.