FMCSA QCMobile API
The Federal Motor Carrier Safety Administration's carrier data API — real-time queries on motor carrier registration, authority and safety data, including all of the passenger carrier data that used to be served by the retired SaferBus API. RESTful, keyed by a free webKey query parameter. This is the only self-serve API credential anywhere in the department: create a Login.gov account, sign in to the FMCSA developer site and generate a key. The developer site publishes a quick start guide, an API access guide, the QCMobile API reference and an API response element reference. FMCSA publishes no OpenAPI.