A trait is a named micro-capability: a partial schema contributing zero or more attributes to the entity that declares it. Composition is commutative and associative; the trait vocabulary is closed and canonical, and a name is never renamed or aliased.

Traits marked (marker) contribute no attributes: they declare a capability whose data lives in edges, which are stored once, outgoing direction only.

Base

Trait	Attributes contributed	Notes
TNamed	name: string	Not universal: lambdas, closures, Rust impl blocks, Java constructors have no own name
TSourceAnchor	anchor: SourceAnchor	Evidence for the entity’s declaration
TComment	comments: string[]	Attached documentation/comments

Containment and attachment

Where an entity is written (lexical containment) and what it semantically belongs to (attachment) are different relations, and both are kept.

Trait	Attributes contributed	Relation expressed
TWithChildren	children: EntityId[] (v1 only, see below)	lexical containment, downward
TChildOf	parent: EntityId	lexical containment, upward — the STORED direction
TAttachedTo	attachedTo: EntityId	semantic attachment. Required by: Go receiver methods, Rust impl blocks, C# extension methods, Clojure extend-type/defmethod

A Go method with receiver (o *Order) is a child of its file/package and attached to Order.

children is an inverse index, not a fact. It is the exact inverse of parent, and inverse views are derived in memory, never serialized. TWithChildren stays a declared trait: it says an entity is a container. Only the serialized key goes.

Modularity

Trait	Attributes contributed	Notes
TModule	definedIn: string[] (CodeFile paths), isStub: boolean	module↔file cardinality varies by language: 1-1 (JS/TS/Python: module is the file), 1-N (Java package, C#/Go/PHP namespace), N-N (Rust inline mod). A stub module has definedIn: [], which is exactly what makes it external

Types

Trait	Attributes contributed	Notes
TType	isStub: boolean	any type-like entity: class, interface, struct, enum, protocol, PHP/Rust trait
TWithInheritances	(marker) — see inheritance edges	multiple inheritance = N edges (Python). Absent from the Go and Rust profiles — that absence is profile information, not a gap
TWithImplements	(marker) — see interfaceImplementation edges
TTypedEntity	declaredType?: EntityId	optional even when the trait is present: absent value in JS/Python/Clojure, C# var, inferred Go/TS/Rust

Behavior

Trait	Attributes contributed	Notes
TInvocable	signature: string	signature is part of identity (Java/C# overloads, Go receivers)
TWithParameters	parameters: EntityId[]	ordered
TWithLocalVariables	localVariables: EntityId[]
TWithInvocations	(marker) — see invocation edges	outgoing only; incoming is derived by the analyzer, never stored

Structure

Trait	Attributes contributed	Notes
TStructural	(marker) — value holder	attributes, variables, parameters, Clojure vars. Legal target of access edges
TWithAccesses	(marker) — see access edges	outgoing only
TWithValue	value: Literal	the entity’s declaration-site constant value. Optional wherever licensed — absence means “not constant”, never “empty”

Measures

Trait	Attributes contributed	Notes
TMetrics	metrics: Record<string, number>	open map of measured finite numbers. Only the extractor writes it

See Measures and literals.

The composition that motivates the design

A Clojure var holding a function is simultaneously named, a value holder, and invocable: traits: [TNamed, TStructural, TInvocable]. No tree-shaped hierarchy can place it; trait composition expresses it directly. The argument is in Why traits.

The closed vocabulary

Nineteen names, in the order the header dictionary’s enum declares them:

TNamed · TSourceAnchor · TComment · TWithChildren · TChildOf · TAttachedTo · TModule · TType · TWithInheritances · TWithImplements · TTypedEntity · TInvocable · TWithParameters · TWithLocalVariables · TWithInvocations · TStructural · TWithAccesses · TMetrics · TWithValue

The keys each contributes on the wire are listed under model.jsonl.