Tooling and Introspection

What you'll walk away with

Explain the core ideas behind Tooling and Introspection
Run the sample GraphQL query or code and verify its output
Apply the technique correctly to the Tutorial Platform and production scenarios

Build the mental model

A GraphQL schema is self-describing: special introspection queries (`__schema`, `__type`) let you ask the API about its own structure at runtime. In-browser IDE tools like GraphiQL and Apollo Sandbox use this introspection data to power autocomplete, inline docs, and live query validation, so developers no longer need a separate schema file open in another tab. In production, introspection is often disabled because it hands an attacker a full map of the schema.

Connect it to a real scenario

In development, browse every type in the Tutorial Platform schema through Apollo Server's default Sandbox, and inspect `Tutorial`'s fields directly with a `__type(name: "Tutorial")` query. Production deployments typically set `introspection: false`.

Schemas are self-describing via introspection queries
GraphiQL/Sandbox turn introspection data into autocomplete and docs
Production deployments often disable introspection

Try the working example

graphql

query IntrospectTutorialType {
  __type(name: "Tutorial") {
    name
    fields {
      name
      type {
        name
        kind
      }
    }
  }
}

You should see

You can use an introspection query to discover a type's fields at runtime.

5-minute try-it

Open Apollo Sandbox or GraphiQL and use the docs panel to browse every field under the root `Query` type of a schema.

One important caution

Leaving introspection enabled on a production API can expose the entire schema — field names, types, deprecated fields — publicly; be careful if any of that reveals sensitive internal naming.

GraphQL — Introspection — GraphQL

Easy traps

Leaving introspection enabled on a production API can expose the entire schema — field names, types, deprecated fields — publicly; be careful if any of that reveals sensitive internal naming.
Validate sample queries and mutations on a local or test server with recoverable data before applying them to production.

Exercise

Open Apollo Sandbox or GraphiQL and use the docs panel to browse every field under the root `Query` type of a schema.

You'll know it worked when: You can use an introspection query to discover a type's fields at runtime.