The name of an API contract should describe the business intent of the API represented within an API contract, focusing on the needs of the API producer and consumers. Let the APIs.json API name represent the business side of each API, and the OpenAPI info title to describe the technical side of each API–this is about the highest level defined by the API contract.
API contracts are meant to contain all of the business and technical details needed to facilitate the relationship between an API producer and consumers, so the name should be something short, sweet, and intuitive–describing what matters to both parties. Try to keep the name as short a possible, but make sure it accurately covers what is happening within each API contract.
Naming is hard, and the name of the contract can be evolved over time as the contract and relationships evolve, but you have to start somewhere. Pick a name, socialize it with all the business and engineering stakeholders involved. Then apply it to the contract knowing that you can evolve it over time, just like other aspects of the APIs covered by the contract.