cwltool software package provides Common workflow language reference implementation, 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 cwltool
cwltool is installed in your system.
Make ensure the cwltool package were installed using the commands given below,
$ sudo dpkg-query -l | grep cwltool *
You will get with cwltool package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Science |
| Package | cwltool |
| Version | 1.0.20160209222805-1 |
| Description | Common workflow language reference implementation |
| Sub Section | Science |