Schemas

Scalar Declarations

scalar HANDLE = string & len(3..24) & pattern(/^[a-z][a-z0-9_]*$/)

Scalar declarations can refine:

• primitive types
• built-in scalar targets
• named scalar declarations

Predicate forms are:

• enum(value1, value2, ...) where each value is a quoted string, integer, decimal number, true, false, or null
• format(NAME) where NAME is one of UUID, EMAIL, NUMBER, DATE, DATE_TIME, TIME, or URI
• len(min..max) for string length checks with inclusive integer bounds; either bound may be omitted as in len(3..) or len(..24), but not both
• pattern(/regex/) for string checks against a slash-delimited regular expression
• range(min..max) for numeric checks with inclusive integer or decimal bounds; either bound may be omitted as in range(0..) or range(..10.5), but not both

Scalar and schema references are resolved after the full preprocessed collection is loaded, so forward references are allowed across the collection preamble and imported fragments.

Schema Declarations

scalar Food = enum("pizza", "taco", "salad")

schema Address {
  city: string
  postalCode: string
}

schema User {
  id: UUID
  email: EMAIL
  birthday?: DATE?
  favoriteFood?: Food
  address: Address
}

schema Users = User[]

• object fields are open by default in v1
• schema fields can reference named scalar declarations alongside built-in scalar targets and other schemas
• field?: Type marks an optional field
• Type? marks a nullable value
• schema Name = Type[] defines a root-array schema

Imported fragments can contribute reusable scalar and schema declarations before request parsing.

Built-In Targets

Built-in scalar targets include:

• UUID
• EMAIL
• NUMBER
• DATE
• DATE_TIME
• TIME
• URI

Those names are reserved and cannot be redefined.

Built-in scalar targets are always available; you do not need to declare them locally.

Assertion Use

^ & body.id === UUID
^ & body.total === NUMBER
^ & body === User

Use schema targets when you want typed validation instead of plain string comparison.