The Empire built M13 to give support, in the form of repairing and refueling, to Imperial vessels operation in the outer borders of the sector, commonly scouts and pickets. Several TIE/LN starfighters were assigned to M13 for its protection.
M13 was a target of Rebel General Lens Reekeene's Operation Retribution. A team was sent there to damage or destroy the post as long as they could avoid important risks for themselves. Reekeene also attacked a nearby station so that M13 would send its fighters there, reducing its protection.
- The Complete Star Wars Encyclopedia