keep current spec unchanged. Appendix C is purely additive

Author: martinbonnin

spec/Section 3 -- Type System.md

@@ -388,10 +388,9 @@ Scalar types represent primitive leaf values in a GraphQL type system. GraphQL
 responses take the form of a hierarchical tree; the leaves of this tree are
 typically GraphQL Scalar types (but may also be Enum types or {null} values).
 
-GraphQL provides a number of
-[built-in scalars](#sec-Appendix-Built-in-Definitions.Scalars) which are fully
-defined in the sections below, however type systems may also add additional
-custom scalars to introduce additional semantic meaning.
+GraphQL provides a number of built-in scalars which are fully defined in the
+sections below, however type systems may also add additional custom scalars to
+introduce additional semantic meaning.
 
 **Built-in Scalars**
 
@@ -1951,12 +1950,10 @@ GraphQL implementations that support the type system definition language should
 provide the `@specifiedBy` directive if representing custom scalar definitions.
 
 When representing a GraphQL schema using the type system definition language any
-[built-in directive](#sec-Appendix-Built-in-Definitions.Directives) may be
-omitted for brevity.
+_built-in directive_ may be omitted for brevity.
 
 When introspecting a GraphQL service all provided directives, including any
-[built-in directive](#sec-Appendix-Built-in-Definitions.Directives), must be
-included in the set of returned directives.
+_built-in directive_, must be included in the set of returned directives.
 
 **Custom Directives**
 

spec/Section 4 -- Introspection.md

@@ -119,10 +119,106 @@ warnings.
 
 **Schema Introspection Schema**
 
-The schema introspection system is itself represented as a GraphQL schema.
+The schema introspection system is itself represented as a GraphQL schema. Below
+are the full set of type system definitions providing schema introspection,
+which are fully defined in the sections below.
 
-See [Appendix C](#sec-Introspection-types) for more details about the schema
-type definitions.
+```graphql
+type __Schema {
+  description: String
+  types: [__Type!]!
+  queryType: __Type!
+  mutationType: __Type
+  subscriptionType: __Type
+  directives: [__Directive!]!
+}
+
+type __Type {
+  kind: __TypeKind!
+  name: String
+  description: String
+  # must be non-null for OBJECT and INTERFACE, otherwise null.
+  fields(includeDeprecated: Boolean = false): [__Field!]
+  # must be non-null for OBJECT and INTERFACE, otherwise null.
+  interfaces: [__Type!]
+  # must be non-null for INTERFACE and UNION, otherwise null.
+  possibleTypes: [__Type!]
+  # must be non-null for ENUM, otherwise null.
+  enumValues(includeDeprecated: Boolean = false): [__EnumValue!]
+  # must be non-null for INPUT_OBJECT, otherwise null.
+  inputFields(includeDeprecated: Boolean = false): [__InputValue!]
+  # must be non-null for NON_NULL and LIST, otherwise null.
+  ofType: __Type
+  # may be non-null for custom SCALAR, otherwise null.
+  specifiedByURL: String
+}
+
+enum __TypeKind {
+  SCALAR
+  OBJECT
+  INTERFACE
+  UNION
+  ENUM
+  INPUT_OBJECT
+  LIST
+  NON_NULL
+}
+
+type __Field {
+  name: String!
+  description: String
+  args(includeDeprecated: Boolean = false): [__InputValue!]!
+  type: __Type!
+  isDeprecated: Boolean!
+  deprecationReason: String
+}
+
+type __InputValue {
+  name: String!
+  description: String
+  type: __Type!
+  defaultValue: String
+  isDeprecated: Boolean!
+  deprecationReason: String
+}
+
+type __EnumValue {
+  name: String!
+  description: String
+  isDeprecated: Boolean!
+  deprecationReason: String
+}
+
+type __Directive {
+  name: String!
+  description: String
+  locations: [__DirectiveLocation!]!
+  args(includeDeprecated: Boolean = false): [__InputValue!]!
+  isRepeatable: Boolean!
+}
+
+enum __DirectiveLocation {
+  QUERY
+  MUTATION
+  SUBSCRIPTION
+  FIELD
+  FRAGMENT_DEFINITION
+  FRAGMENT_SPREAD
+  INLINE_FRAGMENT
+  VARIABLE_DEFINITION
+  SCHEMA
+  SCALAR
+  OBJECT
+  FIELD_DEFINITION
+  ARGUMENT_DEFINITION
+  INTERFACE
+  UNION
+  ENUM
+  ENUM_VALUE
+  INPUT_OBJECT
+  INPUT_FIELD_DEFINITION
+}
+```
 
 ### The \_\_Schema Type