Source: `#/$defs/port`. Local identifier: `interface-model:port`.
### 2. Contract Participation
The association of a Port with a specific InterfaceContract, an offers/requires mode, and contextual roles.
Roles belong to the participation; a port-global role cannot describe every contract context.
Source: `#/$defs/contractParticipation`. Local identifier: `interface-model:contractParticipation`.
### 3. Interface Contract
A semantic agreement organizing operations and their purposes independently of any particular transport realization.
One contract can have multiple bindings; a specification file describes the contract.
Source: `#/$defs/interfaceContract`. Local identifier: `interface-model:interfaceContract`.
### 4. Operation
A named unit of interface behavior within a contract, qualified by interaction style, temporal semantics, effects, and purpose.
A runtime exchange selects or realizes an operation; the operation is not a trace occurrence.
Source: `#/$defs/operation`. Local identifier: `interface-model:operation`.
### 5. Binding
A realization of a contract and selected operations through participating ports, communication stack, addressing, discovery, and optional channel or endpoints.
A second transport can realize the same contract without creating new semantic operations.
Source: `#/$defs/binding`. Local identifier: `interface-model:binding`.
### 6. Endpoint
A concrete locator or selector through which a Binding is reached.
An endpoint may be reused by multiple bindings; it is not the information resource selected through that binding.
Source: `#/$defs/endpoint`. Local identifier: `interface-model:endpoint`.
### 7. Channel
An exchange or mediation locus characterized by delivery, ordering, replay, or retention semantics where known.
A Kafka topic as exchange channel may be backed by a retained-log resource; those roles remain distinct.
Source: `#/$defs/channel`. Local identifier: `interface-model:channel`.
### 8. Interaction
An architectural participation in an exchange linking relevant operation, contract, binding, participants, and channel, with realization status where known.
An interaction can be proposed or rejected; do not equate every interaction with an executed span.
Source: `#/$defs/interaction`. Local identifier: `interface-model:interaction`.
### 9. Interaction Flow
An ordered composition of exchange steps referring to operations, interactions, bindings, and participants.
It expresses composition rather than inventing a new protocol or contract family.
Source: `#/$defs/interactionFlow`. Local identifier: `interface-model:interactionFlow`.
### 10. Information Resource
An identifiable information-bearing object, state, collection, or logical selection that can be addressed independently of a single interaction.
A collection is a resource; its admissible form is a shape, and its access location is not automatically a binding endpoint.
Source: `#/$defs/informationResource`. Local identifier: `interface-model:informationResource`.
### 11. Information Shape
An identifiable semantic or structural type or constraint set describing an admissible information form.
A shape is distinct from an instance, a schema artifact, and JSON or another concrete encoding. Detailed fields remain in describing artifacts. ITC-DATA DataType
and Constraint supply related shared meanings; neither is an automatic shape alias.
