Is there an alternative way to resolve union/interface types without using the Introspection Schema?

[ktmouk]

I noticed the "Heuristic Fragment Matching" warning when I tried to use a union type in the query. After reading the documentation, I understood that the warning can be resolved by passing the introspection schema to the urql client.

However, I want to avoid passing the entire introspection schema if possible. This is because our API is private, and we want to avoid embedding the entire introspection schema in the source code for security reasons.

Is there an alternative way to resolve union/interface types without passing full Introspection Schema?

Apollo Client seems to provide a different approach, called Defining PossibleTypes, which is required to pass the minimal information only.

Related: #3419