TV licence fee staff have been issued with a manual advising that customers who use the words "idiots", "shambles" or "useless" are likely to be making a complaint.
Other indications that a viewer may be unhappy include use of capital letters or the phrases, "When will you people listen?", "Who do you think you are?" and "Sort yourselves out!"
The document also reveals quirks in the rules about who needs a licence - the Queen, prisoners and diplomats do not, but all other Royals and prison officers who live in the grounds of a jail do.
The 964-page official handbook, which was released following a Freedom of Information request, sets out in detail how the fee should be administered.
A large section is dedicated to dealing with complaints, including prepared answers to regular objections about the BBC's "offensive" programmes and the aggressive tone of licence fee warning letters that could "shock" elderly people.
Staff are advised to look out for particular "keywords" suggesting a customer is protesting about some aspect of the £145.50-a-year fee.
These include: "compensation", "complaint", "disgraceful", "disgusted", "incompetent", "appalling", "furious", "intimidation", "mistakes", "harassment", "rude", "threatening", "outrageous", "upsetting", "unacceptable" and swear words.
The document adds: "Remember underlining of key words and phrases or the use of bold or capital letters designed to make certain parts of a letter stand out is also an indication of a complaint."
Officials are given stock answers to common criticisms of the licence, including "The BBC is producing poor programmes, some are offensive, I am only going to pay a proportion of the fee" and "If an old person had received this letter they would have been very shocked".
The two main companies contracted by the BBC to administer the TV licence received 35,000 complaints in 2008 and 37,000 in 2009, according to the TV Licensing website.