Which API Management tools have the best developer portal?
I'm looking for one with swagger and OpenAPI and modern content editor.
In my opinion and experience, I believe that the most complete and customizable Developer Portal are those of IBM (API Connect) and Google (APIGEE), since both are based on CMS Drupal, with all the advantages that this entails.
Have a look at Ceptor API Developer portal (https://ceptor.io/api-management/developer-portal/) a relatively new product on the market.
I found TIBCO Mashery had the best Developer portal. Mashery helped create the API Management category almost over 10 years ago as a SaaS vendor focusing on enabling the developers. try api.bestbuy or api.macy's i think both are good developer portal examples of mashery. OpenAPI/Swagger is just the start with Innovation around Flogo and Mashling facilatating evented APIs built on composable microservices.