claws-mail-spamassassin software package provides SpamAssassin plugin for Claws Mail, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install claws-mail-spamassassin
claws-mail-spamassassin is installed in your system.
Make ensure the claws-mail-spamassassin package were installed using the commands given below,
$ sudo dpkg-query -l | grep claws-mail-spamassassin *
You will get with claws-mail-spamassassin package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | |
| Package | claws-mail-spamassassin |
| Version | 3.14.1-1 |
| Description | SpamAssassin plugin for Claws Mail |
| Sub Section |