GraphQL

Types

Use PascalCase for all named types. Be specific — User is better than Person, UserProfile is better than UserData.

type User {
  id: ID!
  firstName: String!
  lastName: String!
  emailAddress: String!
  createdAt: DateTime!
}

Fields

Use camelCase for all field names:

type Order {
  id: ID!
  placedAt: DateTime!
  totalAmount: Float!
  lineItems: [LineItem!]!
}

Queries and Mutations

Query names use camelCase verbs or noun phrases. Mutation names follow a verbNoun pattern:

type Query {
  user(id: ID!): User
  users(filter: UserFilter, pagination: Pagination): UserConnection
}

type Mutation {
  createUser(input: CreateUserInput!): CreateUserPayload!
  updateUser(id: ID!, input: UpdateUserInput!): UpdateUserPayload!
  deleteUser(id: ID!): DeleteUserPayload!
}

Input and Payload Types

• Input types take an Input suffix: CreateUserInput, UpdateOrderInput
• Mutation return types take a Payload suffix: CreateUserPayload, DeleteOrderPayload

This makes their purpose unambiguous when they appear in generated clients or schema docs.

Enums

Enum type names are PascalCase; enum values are SCREAMING_SNAKE_CASE:

enum OrderStatus {
  PENDING
  IN_PROGRESS
  FULFILLED
  CANCELLED
}

Avoid

# Avoid — abbreviations, inconsistent field names, generic types
type Person {
  uid: String
  fname: String
  surname: String
  email: String
  created: String
}