Having a parameters description provides more depth to what a parameter does and will be displayed via documentation, and other tooling used across the API lifecycle
OpenAPI Components Parameters Description Error
Message: Parameters MUST Have a Description
Policies
Parameter Descriptions
Parameter descriptions tell consumers what each input actually means and how to use it. Without good descriptions, parameters are just names that people have to reverse-engineer.
Centralizing Parameters Using Components
Centralizing parameters in OpenAPI components is how you stop repeating yourself. Define a parameter once, reference it everywhere, and governance gets simpler.