I am new to openstack and came across two projects mistral and monasca. While mistral docs did not mention anything about the repositories and I installed it using devstack adding a single line "enable_plugin mistral https://github.com/openstack/mistral ". While trying to do the same for monasca , I came to know about different repositories of monasco Eg. monasca-api, monasca-agent and so on.

I understand the need for each but not able to understand why are these repositories seperately defined.