Ontology and SHACL authority

Epistemic Graph is the sole runtime authority for OWL/RDF ontology composition, reasoning, Datalog materialization, and SHACL validation. Agent Utilities is a control-plane consumer. It does not load a private root ontology, resolve owl:imports, run a Python reasoner, or validate with a local SHACL engine.

Composition

The immutable EG catalog contains the platform root and domain modules. Each component may contribute versioned semantic resources through an agent-connector-sdk ConnectorContent provider. GraphOS captures those resources and attaches the resulting pack through GraphSchema.AttachPack. GraphSchemaList returns immutable and dynamic source sets plus the catalog and composed digests for the requested graph snapshot.

Agent Utilities contributes one pack resource:

• agent_utilities/ontology/shapes/governance.shapes.ttl

The public provider is agent_utilities.content.agent_utilities_content(). It declares package content only; it does not interpret, attach, or write semantic data.

Runtime contracts

• OwlReason reads the composed GraphSchema and returns digest-bound class and property entailments.
• OwlExplain returns digest-bound class-subsumption proof trees.
• RunDatalogReasoning materializes committed-schema entailments through EG's durable write gateway.
• ShaclValidate with the shapes field omitted validates against the composed GraphSchema snapshot and returns the exact composed digest used.
• An explicit non-empty shapes document is reserved for bounded specialist checks. It is still interpreted by EG and deliberately has no committed-schema receipt.

Governance callers fail closed when a result lacks its required schema digest, reports an inconsistent ontology, or uses the ad-hoc validation mode.

Adding semantic content

1. Put the ontology or shape resource in its owning component package.
2. Register the exact resource with that component's ConnectorContent provider.
3. Add byte, digest, RDF-semantic, and package-data tests in the owning package.
4. Provision the provider through the SDK and attach its pack through GraphOS.
5. Verify GraphSchemaList, reasoning receipts, and validation receipts against the target graph.

Do not add ontology files under agent_utilities/knowledge_graph, introduce a Python fallback reasoner, or pass governance shapes inline.