Spoiler warning: this blog article mentions plot details for The Search for Kalid and VirileMail.
Take a look at the book cover for VirileMail. The story VirileMail explores the question of how a machine with human-like intelligence might come into existence. The book cover "blurb" for VirileMail tries to provide an intellectually stimulating introduction to the topic of artificial human-like intelligence. Hollywood sells science fiction as lowest-common-denominator "adventure" or "horror", but true science fiction involves itself with intelligent explorations of the social implications of science and technological change. I'm now thinking about creating a "cover blurb" that describes the sciences and technology issues that are central to The Search for Kalid.
Like VirileMail, The Search for Kalid also concerns itself with machine intelligence. There are many human-like robots in the story and the spaceships have built-in artificial intelligences. However, machine intelligence, like nanotechnology, is not the main technological topic of concern in the story. The main issue is telepathy.
In VirileMail the "plot device" that "explains" how a machine with human-like intelligence is created involves "nanobots", nanoscopic devices that can cooperate and assemble to form a human-like intelligence. A human mind can be produced by the cooperative interaction of the neurons in a human brain and an artificial intelligence can be produced by the cooperative interaction of a collection of nanobots or "nanites". In VirileMail, the sudden advance towards production of an artificial human-like intelligence is made possible by aliens who bring their advanced nanotechnology to Earth. One of the characters (Janek) is essentially an alien (Janek's life history is rather complicated, but he is of alien origin).
For The Search for Kalid, there are no alien characters in the story. However, the existence of human telepathy is due to genetic engineering that was performed on humans by aliens thousands of years ago. The aliens are no longer around, but the genes needed for telepathy remain in the human gene pool. You can think of that "alien intervention" as a plot device that makes telepathy possible in The Search for Kalid.
A major aspect of The Search for Kalid is the elements of mystery that are in the story. How can you make an informative cover blurb without spoiling the mystery of the story for readers? What I tried to do for the VirileMail cover blurb was raise the general issue of how machine intelligence might be created without giving away what happens in the story. Similarly, a good cover blurb for The Search for Kalid would get the reader thinking about telepathy without saying how telepathy is handled in the story. However, the The Search for Kalid starts by showing a main character who thinks about telepathy in terms of a spiritual phenomenon. It is only with time that the story reveals the scientific basis for telepathy. Even worse, most people in the story do not think that telepathy is possible at all! Can anything be said in a cover blurb about a science of telepathy without spoiling the start of the story where telepathy is introduced from a religious perspective?