Hermits are one of the "lost" Hunter creeds who follow the virtue of Vision. While other hunters may only hear the voices of the Messengers when they are first imbued, Hermits hear them constantly, causing an ever-present sensory 'static' in their minds - and find it gets worse in the presence of monsters or other hunters. Consequently they earn their name by hiding from the world, seeking to quiet the voices in their heads. They find, however, that they are unable to ignore what they learn from the Messengers, and attempt to act on that information as best they can, communicating what they learn to other hunters.
Prior to their imbuing, a Hermit will tend to fit certain criteria: skilled in some form of communication, emotionally detached, socially withdrawn, and/or reluctant to endanger themselves, but still wishing to get involved.
The Hermit Edges can roughly be divided into three categories: those that allow the Hermit to project themselves elsewhere, such as Reach or Transcend; those that allow the Hermit to communicate what they've learned to other imbued, such as Send; and those that allow the Hermit to channel the Messengers, such as Edict or Proclaim. Taken together with the typical Hermit profile, this suggests that the Hermits' intended role for other imbued was to act as "intelligence officers" - gathering information, both on their own and from the Messengers, conveying that information to other imbued, and acting as vessels for the Messengers' will should the need arise.
The Hermits' special ability is the 'message in a bottle'; strictly speaking, however, it's not under the Hermit's control. Every so often, a Hermit will feel compelled to set down what they've learned so far, be it on paper, via email, on audio or video - any medium will do, so long as it's one that records and conveys information. The Hermit then casts the message out into the world, and the Messengers see to it that the message is received by other hunters.