The info description for each of your APIs should be one to three paragraphs long and tell the technical narrative of your API resources and capabilities. Don’t repeat things already declared in other areas of your business contract, avoid talking about infrastructure and protocols, and focus on what your consumers will be needing. The technical description of your API should focus on the paths, methods, and operations of your API, and the solutions your consumers are looking for, not how you developed your API.
Work to keep code out of your description, leveraging examples through your OpenAPI definition to document the technical details. The info description is meant to be a medium form narrative description of the value your API provides to an API consumer. It isn’t your narrative of how you got here, it is the narrative for helping onboard API consumers with what they need in their applications and integrations. Putting yourself into your consumers shoes when writing the info description for your API is where anyone should start to craft just the right message.