The OpenAPI operation parameter in property allows you to designate whether a parameter is used in the path, via query, or is a header. These are the three distinct dimensions for configuration of API requests by the consumer, and should be considered as a whole, but they deliver some very different outcomes depending on how they are used.
The parameter in property represents three dimensions of the design of an API, augmenting the path, as well as potentially request bodies with different ways API consumers can be equipped to put an API to work. The OpenAPI parameter in property forces us to pause for a moment and think about what type of control we are giving to user and how it will shape each API response.