From the website:
The daily life of a Spy in service to the Rebellion is one of flexibility and innovation. Every mission poses a new question that must be answered with minimal supplies and personnel against a foe with a surplus of both. The Rebellion relies on the ingenuity and skill of every single operative on their roster. Today, we’re going to look a little closer at the secrets revealed in the newest Star Wars™: Age of Rebellion sourcebook, Cyphers and Masks.
In a galaxy filled to bursting with technology and networks and computer systems, tech experts like Slicers access streams of data to manipulate and control the flow of information. However, not everything of value is in code or safe on the holonet. Couriers are spies who specialize in the safe and secure movement of secrets and supplies. Where the previously revealed Sleeper Agent excels at social engineering and a carefully constructed legend, the Courier navigates physical space with similar deftness. Their training and skill at maneuvering through dense urban areas allows them to get where others can’t. Towering buildings, crowds of civilians, clutter-strewn alleys, and more are the preferred environments of the Courier.
Couriers are experts at operating deftly in enemy territory where the watchful eye of the Empire is ever present. Multiple ranks of the Indistinguishable talent upgrade the difficulty of observers to recognize and identify the character, and an Improved version extends this benefit to nearby allies. To represent their ability to navigate their surroundings where others would find difficulty, the talent Freerunning allows the Courier to spend 1 strain to move, even vertically, to any location within short range provided there is a path to do so.