Describe the pattern in ordinary terms.
Water over an edge, a drip at a bend and a damp patch on paving are different observations. Note when each happens, using earlier photographs or notes if available. Leaves and twigs can build up in gutters, along with fallen moss fragments. Clearing that material is not treating moss on the roof.
Visible plant growth or a section that looks loose is worth mentioning. Do not climb closer, reach into the gutter or disconnect a pipe to check. An observation can guide the assessment without being proof that cleaning alone will resolve the concern.