Guide for writing GraphQL operations (queries, mutations, fragments) following best practices. Use this skill when: (1) writing GraphQL queries or mutations, (2) organizing operations with fragments, (3) optimizing data fetching patterns, (4) setting up type generation or linting, (5) reviewing operations for efficiency.
This guide covers best practices for writing GraphQL operations (queries, mutations, subscriptions) as a client developer. Well-written operations are efficient, type-safe, and maintainable.
query GetUser($id: ID!) {
user(id: $id) {
id
name
email
}
}
mutation CreatePost($input: CreatePostInput!) {
createPost(input: $input) {
id
title
createdAt
}
}
subscription OnMessageReceived($channelId: ID!) {
messageReceived(channelId: $channelId) {
id
content
sender {
id
name
}
}
}
| Pattern | Example |
|---|---|
| Query | GetUser, ListPosts, SearchProducts |
| Mutation | CreateUser, UpdatePost, DeleteComment |
| Subscription | OnMessageReceived, OnUserStatusChanged |
# Required variable
query GetUser($id: ID!) { ... }
# Optional variable with default
query ListPosts($first: Int = 20) { ... }
# Multiple variables
query SearchPosts($query: String!, $status: PostStatus, $first: Int = 10) { ... }
# Define fragment
fragment UserBasicInfo on User {
id
name
avatarUrl
}
# Use fragment
query GetUser($id: ID!) {
user(id: $id) {
...UserBasicInfo
email
}
}
query GetUser($id: ID!, $includeEmail: Boolean!) {
user(id: $id) {
id
name
email @include(if: $includeEmail)
}
}
query GetPosts($skipDrafts: Boolean!) {
posts {
id
title
draft @skip(if: $skipDrafts)
}
}
# Good: Specific fields
query GetUserName($id: ID!) {
user(id: $id) {
id
name
}
}
# Avoid: Over-fetching
query GetUser($id: ID!) {
user(id: $id) {
id
name
email
bio
posts {
id
title
content
comments {
id
}
}
followers {
id
name
}
# ... many unused fields
}
}
# Good: Named operation
query GetUserPosts($userId: ID!) {
user(id: $userId) {
posts {
id
title
}
}
}
# Avoid: Anonymous operation
query {
user(id: "123") {
posts {
id
title
}
}
}
# Good: Variables
query GetUser($id: ID!) {
user(id: $id) {
id
name
}
}
# Avoid: Hardcoded values
query {
user(id: "123") {
id
name
}
}
// UserAvatar.tsx
export const USER_AVATAR_FRAGMENT = gql`
fragment UserAvatar on User {
id
name
avatarUrl
}
`;
function UserAvatar({ user }) {
return <img src={user.avatarUrl} alt={user.name} />;
}
Detailed documentation for specific topics:
id field for cacheable types@include/@skip for conditional fields