Hot Chocolate provides a wide range of attributes that you can apply to your .NET types, properties, methods, and parameters to configure the GraphQL schema. This page serves as a comprehensive reference.

Root Type Attributes

These attributes mark a class as a root operation type for your schema.

Type Configuration Attributes

These attributes control how .NET types map to GraphQL types.

Data Fetching Attributes

These attributes configure data loading and resolver behavior.

Authorization Attributes

Error Handling Attributes

Cost Analysis Attributes

Caching Attributes

Identity Attributes

Resolver Parameter Attributes

These attributes control how parameters are injected into resolvers.

Subscription Attributes

Data Middleware Attributes

These attributes apply middleware to fields for pagination, filtering, sorting, and projection.

Middleware ordering matters. The correct attribute order from top to bottom is: [UsePaging], [UseProjection], [UseFiltering], [UseSorting].

Mutation Convention Attributes

Relay / Global Object Identification Attributes

Schema Design Attributes

Fusion / Federation Attributes

These attributes are used when building Fusion subgraphs or Apollo Federation subgraphs.

Custom Descriptor Attributes

You can create custom attributes to package descriptor configurations for reuse. Hot Chocolate provides base classes for each descriptor type:

• ObjectTypeDescriptorAttribute
• ObjectFieldDescriptorAttribute
• InputObjectTypeDescriptorAttribute
• InputFieldDescriptorAttribute
• InterfaceTypeDescriptorAttribute
• InterfaceFieldDescriptorAttribute
• EnumTypeDescriptorAttribute
• EnumValueDescriptorAttribute
• UnionTypeDescriptorAttribute
• ArgumentDescriptorAttribute

Each base class pre-configures the allowed attribute targets. For example, ObjectFieldDescriptorAttribute is valid only on methods and properties.

public class UseMyMiddlewareAttribute : ObjectFieldDescriptorAttribute
{
    public UseMyMiddlewareAttribute([CallerLineNumber] int order = 0)
    {
        Order = order;
    }

    protected override void OnConfigure(
        IDescriptorContext context,
        IObjectFieldDescriptor descriptor,
        MemberInfo member)
    {
        descriptor.Use(next => async ctx =>
        {
            // Custom logic
            await next(ctx);
        });
    }
}

For attributes that target multiple descriptor types, use the DescriptorAttribute base class:

[AttributeUsage(
    AttributeTargets.Property | AttributeTargets.Method,
    Inherited = true,
    AllowMultiple = true)]
public sealed class MyCustomAttribute : DescriptorAttribute
{
    protected override void TryConfigure(
        IDescriptorContext context,
        IDescriptor descriptor,
        ICustomAttributeProvider element)
    {
        if (element is MemberInfo member)
        {
            switch (descriptor)
            {
                case IInterfaceFieldDescriptor interfaceField:
                    // Configure interface field
                    break;

                case IObjectFieldDescriptor objectField:
                    // Configure object field
                    break;
            }
        }
    }
}

Next Steps

• Building a schema for type system configuration
• Field middleware for creating custom middleware
• Resolvers for field resolution patterns