GraphQL API: introspection limit is too restrictive

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Context

For a GraphQL client to use a GraphQL API, it needs its schema. To do this, introspection is usually available, allowing the client to retrieve all types, fields, directives, etc., via an introspection query.

However, depending on the server's GraphQL capabilities, this introspection query could request for fields that are not supported (e.g. specifiedByURL introduced in 2021), which will result in errors.

To alleviate this issue, a client can execute a "pre-introspection" query first, to see which introspection features are supported by the server, and then craft a compatible introspection query.

This is what Apollo Kotlin does.

Issue

This pre-introspection query fails on GitHub's server, with INTROSPECTION_LIMIT_EXCEEDED:

query PreIntrospectionQuery {
  schema: __type(name: "__Schema") { ...TypeFields }
  type: __type(name: "__Type") { ...TypeFields }
  directive: __type(name: "__Directive") { ...TypeFields }
  field: __type(name: "__Field") { ...TypeFields }
  inputValue: __type(name: "__InputValue") { ...TypeFields }
}

fragment TypeFields on __Type {
  fields {
    name
    args {
      name
    }
  }
}

This is disappointing, especially since this version of the query, which results in a much bigger response, is allowed:

query PreIntrospectionQuery {
  __schema {
    types {
      ...TypeFields
    }
  }
}

fragment TypeFields on __Type {
  name
  fields {
    name
    args {
      name
    }
  }
}

If the introspection fields limit could be changed from 2 to 5, the more optimized version would work on GitHub.