Poisoned Pen
The CIA was happy to use other people to do their dirty work for them and just supply the means to get the job done. This was evidenced by the willingness to hire the mob. But the mob was not the only group that they worked with. They had a number of different informants, insurgents, and operatives working in Cuba whose ties to the CIA were somewhat dubious. In most cases the CIA wanted to be able to deny any association with anyone working in Cuba if things failed or if they were successful.
In the early 1960s, there was a senior Cuban official known as AM/LASH that was in communication with the CIA. Every person in the CIA that ever talked to AM/LASH explicitly stated that they did not ask this person to assassinate the foreign leader. The records and evidence tell a much different story.
The CIA gave AM/LASH an arsenal full of high-powered rifles and scopes that were meant to take out Castro from afar. But just in case AM/LASH got close to him, they also provided a ball-point pen that was rigged with a hypodermic needle. According to the CIA the needle was so fine that it could be inserted into someone and they would never feel it or notice they had been injected.
AM/LASH was not impressed by the pen. According to his case officer, he complained that the CIA should create something a little more sophisticated than the poison pen. Considering the other attempts by the CIA had including an exploding cigar and a poisoned wet suit… AM/LASH might have been expecting a little too much from the 1960s CIA.