The entire specification is outside of the nips repository. What's the point? nips are a mess. Everything a developer could need to work with CVM is available at

ContextVM Documentation

ContextVM

The intersection of Nostr and MCP

But in summary each CVM server self-describes its API using JSON schema. We are also working on a 'common schema' specification so that services can adhere to a common schema. For example, Relatr could define a common schema that other instances of it or other services can use to be interoperable, as they would have the same API.