In various material at the Cassiopaea site, this word is sometimes used to designate individuals who either deliberately or unconsciously seek to derail the efforts of another towards spiritual progress or towards fulfillment of a personal mission.
Being an 'agent of the matrix' does not generally involve any direct relationship with any secret service or the like, although such is also not precluded.
Being an 'agent of the matrix' does not either always involve personal ill will. For example, family members with ostensibly the best intentions may be great hindrances for a person's spiritual quest while sincerely believing to be only helpers and protectors.
The concept has great potential for exaggeration and self-importance. One should not self-importantly assume that the mere fact of dealing with difficult or tiresome people means that one is at the brink of a great spiritual revelation that the matrix fights tooth and nail to repress. On the other hand it has been seen time and again that people benefit from distancing themselves from habitual draining relationships.
Sometimes the activity is psychic only, without spying or overt conflict or disagreement. Sometimes the activity consists of generating constant worry, as in the case of family members. The Wave and Adventures with Cassiopaea series contain many examples.