Question: I'm looking for a collaborative API design platform that supports multiple stakeholders.

If you're looking for a collaborative API design platform with multiple stakeholders, ReAPI is a good choice. It has a visual API designer based on OpenAPI, augmented by AI and ChatGPT to generate schema, examples and documentation. It also has a no-code test case designer, a serverless cloud runner and detailed test reports. ReAPI supports collaboration with internal and external users, versioning and permission controls, so teams can work together and publish APIs to a public gallery.

Another good choice is Conektto. It automates API integrations with generative design, code and test abilities powered by AI. Conektto includes an API Design Studio for designing and simulating API contracts, an API Test Harness for automated testing, and an Enterprise API SDLC for an end-to-end API development lifecycle. It's designed for multiple stakeholders including product managers, developers and DevOps teams, and offers free and paid tiers.

For a lightweight API development and testing tool, check out ApyHub Fusion. The platform has a visual API design and development editor, API testing that automatically generates tests, and API documentation with AI assistance. It also supports OpenAPI, Swagger 2.0 and RAML, and integrates with tools like Slack and Datadog for real-time monitoring and alerting. ApyHub Fusion has several features for team collaboration, including secure workspaces and real-time commenting.

Last, Theneo is a good API documentation tool that uses AI to generate high-quality documentation with a minimal amount of human involvement. It supports several platforms, including OpenAPI, Postman and GraphQL, and has features like automated updates, custom branding and ChatGPT integration. Theneo can handle large numbers of API projects with its scalable pricing plans, so it's good for teams of all sizes.