This subject is of big interest to me and I am happy to see other websites picking up the concerns and expressing them publicly.
I have crossed paths with these undercover agents many times, on various websites and forums, and a I can tell you from my first hand experience that they are extremely effective.
They are usually intelligent and well informed people, and a couple of them operating on each section of a forum, are enough to kill a subject of major interest almost immediately.
I. CIA-Sponsored Trolls Monitor Internet and Interact With Users to Discredit Factual Information
“In July (2012) it became apparent through a flood of mainstream media reports that the National Security Agency (NSA) was ‘desperate to hire new hacking talent to protect the nation’s critical infrastructure’ yet the NSA is notorious for its surveillance programs on American digital activity…
David Petraeus, former director of the CIA, is seeking to better the CIA’s ability to create online identities for undercover spies.” , [2 nsa.gov], ;
“David Petraeus essentially admitted that the CIA has a covert online presence that it uses not only for data mining purposes but also to infiltrate online conversations for the purpose of protecting ‘national security’ interests.
Such interests, it turns out, include disrupting conversations that discuss topics like 9/11 truth, for instance, or U.S. involvement in giving weapons to Syrian rebels.” 
II. Their work can be summed up into 5 major categories:
1. They combine their vast knowledge with disinformation and ridicule, in order to make a subject appear as uninteresting and misleading as possible.
2. At the same time, they fuel meaningless debates on uninteresting subjects, easily diverting attention from the important ones — while keeping the first page of a forum filled with subjects bringing nothing new or crucial, and acting merely as distractions.
3. If a given subject is of major interest and they are not able to instantly kill it, then they will divert the discussion to one of the never-ending “divide and conquer” debates, like politics, racism, war, etc.
4. They work together to report those who are informed for things they have not committed, like copyright infringement or spam, in order to have their accounts suspended; or provoke them systematically, looking for an offensive reaction that is sanctioned by the forum rules.
5. Finally, they infiltrate the high ranks of a forum or website, becoming “moderators”. This gives them power to delete threads of interest, due to fake copyright infringement reported by their undercover colleagues, and they can go as far as permanently banning a user.
III. One of my first hand experiences: a permanent ban
I’ve had my account deleted and all my articles and comments removed from a major conspiracy forum, where huge numbers of undercover “agents” (too much of a word for these governmental lackeys) operate, due to copyright infringements to… myself!
After bringing to their attention that I was the one who wrote the articles, they’ve accused me of advertising. In the forum rules it was mandatory to include a link back to the article’s source, but in my case it was considered advertisement.
The forum’s moderator explained in the same email that he received numerous reports from various users, accusing me of the already mentioned rule infringements.
I’ve received no previous warning and offered no chance to “redeem” myself. All my future emails explaining the situation in a civilized manner (and even offering to remove the source links), were completely ignored.
IV. How to spot the internet trolls
If you are a forum moderator, site owner or concerned member of a community, and you want to flush the undercover trolls out, then you should pay attention to the following behavioral patterns:
– They usually post discrediting messages in groups, supporting each other’s claims, while demoting, ridiculing or spreading disinformation in all interesting threads. These trolls are usually very active and they are the first ones to post replies — because this is what they are payed for.
(You will notice on some forums that the first half dozen to a dozen replies are ridiculing the subject or spreading disinformation on the subject. This method is casting a dark shadow on the thread, and not many people will see through their fog of lies).
– Their overall activity in other people’s threads is not constructive. They are always in contradiction to the thread’s OP and with those who support it.
– They usually support each other’s threads, making them even easier to unmask.
– Their threads are usually about the already “drained” subjects like the Roswell incident or JFK’s assassination – where they allegedly try to bring new light to the subjects; they post a lot about Masonry for some reason that I don’t fully understand, and, of course, they encourage everyone to take violent actions against the government (which is exactly what the government wants).
– Their avatars are in contrast to the main theme of the forum.
(For example, those who were ridiculing spiritual subjects on spiritual forums, had negative avatars depicting: Satanic or Masonic symbols, violence, mocking spirituality, etc.).
– They are very active and part of many groups and communities, but they are mainly activated by specific subjects — those they know best.
– It is very probable that they have applied in the past for the “moderator” role and they are periodically reporting users who infringe the forum’s rules (many times wrongfully).
V. What can you do about it?
If you are a user and you spot one of these undercover agents, please report them to a forum moderator, and bring as much evidence as possible to support your claims.
By Alexander Light, HumansAreFree.com