Mechanism
Versioned policies are the disclosed means by which the agent schema evolves without breaking the objects already authored under it. Updates to schema definitions, including the introduction of revised field constraints, additional semantic templates, or modified fallback inference rules, are governed through versioned policies identified by the policy reference field. The policy is not an external configuration that a runtime consults out of band. It is named directly by a canonical field embedded in the semantic agent object itself, so the governing version travels with the object rather than being supplied by whatever environment happens to evaluate it.
Because the policy reference field is one of the six canonical fields of the schema, alongside the intent field, context block, memory field, mutation descriptor field, and lineage field, the version under which an object was authored is part of the object's structural state. A node interacting with the object determines structural coherence from the presence of canonical fields and structural compatibility from the rules governing whether those fields are permitted to coexist, and it does so based only on information embedded within the object. The governing policy version is part of that embedded information, which is what allows evaluation to be deterministic and independent of any centralized validation authority.
The Policy Reference Field
The policy reference field identifies one or more governing policies that define constraints on permissible behavior, mutation pathways, delegation authority, semantic scope, or trust thresholds applicable to the semantic agent object. The field does not embed the policy text. It names policies, and those policies are resolved at validation time. Policies identified by the policy reference field may point to internal policy objects, external policy identifiers, or decentralized aliasing mechanisms, provided that such references are resolvable and verifiable at validation time. This is the only constraint the disclosure places on how a reference is expressed: it must resolve and it must be verifiable when validation occurs.
This indirection is what makes versioning possible. Revising a schema does not mean rewriting objects. It means publishing a revised policy and letting objects continue to name the version they were authored under, while newly authored objects name the revised version. The policy reference field enables distributed enforcement of governance rules without reliance on centralized authorities or monolithic control systems, because each object carries the identifier of the version that governs it and any node can resolve that identifier independently.
Interoperation Across Schema Versions
The disclosure addresses the central problem of evolving a schema in a population that cannot be upgraded all at once. Semantic agent objects instantiated under earlier schema versions may interoperate with agents instantiated under later versions, provided that field coherence, lineage continuity, and policy resolution remain valid under the governing contracts. Interoperation is therefore not unconditional. It is conditioned on those three properties holding together: the fields present remain coherent, the lineage chain remains continuous, and the policies named by each object resolve validly under the contracts that govern them.
These conditions reuse the same structural evaluation that governs every interaction in the schema. When a partial semantic agent interacts with a full semantic agent, the interaction is evaluated based on field coherence rather than role identity or execution context. Cross-version interoperation works the same way: an object authored under an earlier version is admissible to the extent its fields cohere and its policy reference still resolves, not because of any synchronized migration event applied across the population. Older and newer objects coexist, and each is evaluated against the version it names.
Structural, Declarative Policy Evaluation
Policy evaluation in the disclosed schema is structural and declarative and is not dependent on execution history external to the semantic agent object. A node does not replay an object's runtime history to decide whether it complies. It resolves the policies named in the policy reference field and evaluates the object's embedded fields against the constraints those policies declare. The disclosure defines this behavior as schema-deterministic: identical semantic agent object structures, evaluated under identical policy references and contextual parameters, yield identical validation, mutation-eligibility, and structural scaffolding outcomes, independent of execution environment, runtime scheduling, or transport medium. This determinism is what lets versioned governance operate across heterogeneous and stateless environments without a shared session or a central arbiter.
The policy reference field also operates in conjunction with adjacent fields. Mutation descriptors operate in conjunction with policies identified by the policy reference field, context metadata, and lineage constraints to ensure that any evolution of the agent's intent, role, or structural composition stays within authorized transformation pathways. The governing policy version therefore bounds not only the object's present validity but the set of mutations it is permitted to undergo, so versioning constrains evolution as well as static structure.
Lineage and Policy Continuity
Versioned policies compose with the schema's lineage field to preserve governance history across agent generations. Each lineage reference preserves trust inheritance, policy continuity, and mutation provenance across agent generations, and at no point is lineage rewritten, collapsed, or implicitly inferred. Every lineage relationship is explicitly recorded within the agent objects themselves. As a result, the policy version that governed each ancestor remains recoverable from the chain rather than being lost when the schema moves forward.
Lineage validation is performed structurally by evaluating the lineage field in conjunction with memory trace outcomes and policies identified by the policy reference field. A node can verify that a descendant's governing policy is consistent with the policy continuity recorded along its ancestry, so a transition from one schema version to another is auditable as part of the object's recorded provenance rather than as an opaque or external event.
Reference Embodiments
The disclosure leaves the form of the policy reference open while fixing its required properties. A policy reference may point to an internal policy object carried alongside the agent, to an external policy identifier maintained outside the object, or to a decentralized aliasing mechanism, provided in every case that the reference is resolvable and verifiable at validation time. Internal references suit closed populations where the governing definitions travel with the objects. External identifiers suit deployments where policies are administered centrally. Decentralized aliasing suits federated or trustless deployments where no single authority holds the policy registry.
Across these embodiments the schema-level evaluation model is unchanged. The use of cryptographic binding is optional and does not alter the schema-level validation model, which remains independent of any specific cryptographic implementation. A deployment may bind references cryptographically to make tampering detectable during structural validation, but the versioning mechanism does not depend on it. What the mechanism requires is resolvability and verifiability at validation time, not any particular substrate, registry topology, or cryptographic scheme.
What Distinguishes This Approach
In conventional agent systems, governance constraints are typically maintained outside the agent representation, in application logic, workflow engines, or session-scoped state. When the governing rules change, the binding between an agent and the version of the rules that authored it is held by the environment, not by the agent, so evolving the rules risks silently re-governing objects that were never authored under the new version. The disclosed schema moves the binding into the object: the governing version is named by the policy reference field, embedded among the canonical fields, and evaluated structurally.
By embedding governance, integrity enforcement, and provenance tracking within the semantic agent object itself, decentralized systems are able to reason deterministically about semantic validity, mutation authorization, and trust inheritance. This eliminates dependence on centralized validation authorities and supports scalable, auditable semantic execution across heterogeneous and stateless environments. Versioned policies are the schema's expression of that principle applied to change over time: the schema can evolve while every object continues to be evaluated against the version it names, with cross-version interoperation granted precisely when field coherence, lineage continuity, and policy resolution remain valid under the governing contracts.
Disclosure Scope
The disclosure encompasses versioned policies as the means of governing updates to schema definitions, including revised field constraints, additional semantic templates, and modified fallback inference rules; the policy reference field as the canonical field that identifies one or more governing policies and that may resolve to internal policy objects, external policy identifiers, or decentralized aliasing mechanisms, provided such references are resolvable and verifiable at validation time; the interoperation of objects instantiated under earlier schema versions with objects instantiated under later versions, conditioned on field coherence, lineage continuity, and policy resolution remaining valid under the governing contracts; the structural and declarative character of policy evaluation, which does not depend on execution history external to the object; and the preservation of policy continuity across agent generations through the lineage field. The use of cryptographic binding is described as optional and does not alter the schema-level validation model. These elements are disclosed in U.S. Application No. 19/452,651. This article describes that disclosed mechanism and does not assert version-numbering schemes, compatibility tables, migration languages, deprecation structures, audit-chaining constructs, or performance figures beyond what the disclosure provides.
