matrix-send
Send messages to matrix from command line. Usage example:
$ ./matrix-send.py "Hello world!"
Configuration
Copy the config.ini.template file to ~/.config/matrix-send/config.ini and fill the fields:
[DEFAULT]
endpoint=https://matrix-server:8448/_matrix/
access_token=
channel_id=
msgtype=m.notice
Getting the access_token and channel_id values
Please, refer to matrix' documentation: https://matrix.org/docs/guides/client-server.html