Route planning for Berlin public transport (BVG) using the v6.bvg.transport.rest API. Use when the user asks for: (1) route suggestions between two addresses or stops, (2) live next-departure info for a stop, (3) arrival-time–based journey planning (arrive-by or depart-at). Supports outputting 2–3 options ranked by travel time, transfers, and walking, and returning step-by-step directions and refresh tokens for live updates.

使用 v6.bvg.transport.rest API 为柏林公共交通（BVG）规划路线。当用户请求以下内容时使用：（1）两个地址或站点之间的路线建议，（2）某个站点的实时发车信息，（3）基于到达时间或出发时间的行程规划。支持按旅行时间、换乘次数和步行距离排序输出2至3种方案，并提供逐步导航指引及用于实时更新的刷新令牌。