Routes can carry written turn-by-turn steps

steps=true on /route, /match and /optimized-route adds written directions, one per maneuver, in English or French: each step's instruction, distance, duration, start point and its stretch of the route line, for a directions list in a web or mobile app. There is no voice narration.

• Step types and modifiers are unmap's own names (turn, keep, exit, roundabout, transit...), so your code does not depend on the routing engine's numbering
• geometryRange indexes the returned line, so a hovered step can be highlighted on the map without a second geometry
• lang=fr writes French; without lang the gateway follows Accept-Language. The French comes from the engine's France French locale, so some phrasing reads as European French