Having a length limitation for each description of each API operation helps apply constraints to how you describe your APIs, while helping drive consistency across APIs when it comes to search, documentation, and other ways an API is made available.
OpenAPI Operations Description Length Error
Message: Operation Description MUST Be Less Than 250 Characters
Policies
Description of API Operations
Operation descriptions are where you explain what each endpoint actually does. A missing or weak description means consumers have to guess, and guessing leads to bad integrations.