My co-worker Adib did a video showing how to use Spring HATEOAS to make existing REST APIs agent-friendly. Instead of wrapping your 700 APIs as MCP servers and dumping all those tool definitions into the context window, you build a an adapter layer that lets agents discover what they can do by following links in the spirit of the World Wide Web REST thinking from long ago: HATEOAS.
Progressive disclosure
This method is geared around minimizing context window usage for especially large APIs. As the AI follows links, it learns more. For example, if you have the API to get a person’s bank accounts, it can then “follow the link” to a bank account to get more info - rather, to get the API and info for getting the account details. Then it can follow the link to the ledger, getting the API and details. Then the individual transactions. And so, and so on. Like skills, it’s progressively discovering what the APIs are and preserving the context window.
Permissions
This also give you more power over access and permissions. On the server side, you can determine what API and datas you expose to AIs walking over the data. You could turn off transaction details, you could mask the edit being sent back to remove PII, etc.
Just turn it on
The other nice thing is that HATEOAS and REST are very well understood and, thus, easy to implement. As Adib shows, you can kind of just unleash a standard HATEOAS pattern or library onto an API and have it map it, like Spring HATEOAS. This gives you another layer of control as well. It also means you can use standard HTTP auth, and I assume all the day 2 stuff like load balancers, caching, etc. It’s all just web traffic to that stuff.
Anyhow, it’s a cool idea. Check out the video.