400 Billion Stars by Paul McAuley
Dorothy Yoshida is a telepath, and a really rather good one at that.
She's also a scientist, and when a small planet begins to manifest some unusual signs she is sent to investigate. The planet is more than it seems, and on further investigation the scientists begin to suspect it has been artificially altered.
But despite their suspicions the only life they can detect is on the surface, none of which has advanced far above the level of animals. And despite the hopes of mankind to find something which will help them in a burgeoning war against other species, there seems to be nothing there to aid them.
With Dorothy's arrival, however, they are in for some surprising discoveries.