Yes. All coaches appear in the participant message stream and are available to pull in through @-mention. The primary coach receives a notification every time a message is sent. Support coaches only receive notifications if another member of the care team or the participant @-mentions them. After they are mentioned, the support coach must unwatch the conversation to stop getting notifications from the messenger stream.
Participants may also view all members of their care team, as well as their group(s) membership, by navigating to their Me page.