Human: Produce a detailed written description of a dreary scene inside a tunnel with pebbles and a pool. Assistant: 
Tiny rivulets slip down the northern and southern passages and meet in the center of the tunnel's floor where they create a tiny pool. Rounded, white pebbles form a small barrier around the pool that prevents it from spilling into the main walking area of the passage. A ragged torch provides illumination for the immediate area, though it does little to illuminate the incline to the north.