trust-systems-meta-model

Trust Infrastructure Schemas Alignment

TSMM and Trust Infrastructure Schemas (TIS) are now aligned as a two-layer executable-governance stack. The purpose of this document is to prevent semantic drift by making ownership boundaries explicit.

Canonical layering

Layer Repository Primary responsibility Output
Semantic model trust-systems-meta-model Define portable concepts for entities, authority, delegation, policy, evidence, lifecycle state, verification, trust decisions, operational effects, and runtime governance. Graphs, bindings, profiles, crosswalks, model examples.
Executable artifact contracts trust-infrastructure-schemas Define machine-validatable artifact shapes for authority boundaries, evidence bundles, evaluation envelopes, decision receipts, registry entries, assurance, controls, and artifact references. JSON Schemas, examples, validation coverage, artifact taxonomy.

Operating rule

Model meaning in TSMM. Package and validate evidence in TIS. Preserve enough references that an auditor can move from a TIS artifact back to the TSMM concept, node, edge, or decision it implements.

Scope and authority

TSMM owns the abstract meaning of authority. TIS owns the artifact contract for bounded reliance on authority. This distinction matters because authority exists as a governance relationship before it becomes an artifact claim.

A TIS authority boundary is therefore not a replacement for a TSMM authority graph. It is an artifact-level projection of a bounded portion of that graph.

Enforcement and revocation

Both repositories apply the same rule: discovery is not authorization. Registry publication may make a trust fact discoverable, but runtime authority must still be checked against policy, evidence, scope, revocation state, and requested effect.

Evidence and auditability

The aligned stack SHOULD produce the following evidence trail for runtime reliance:

TSMM authority graph -> TIS authority boundary -> TIS evidence bundle -> TIS evaluation envelope -> TIS decision receipt -> TIS registry entry

The decision receipt is the audit pivot. It binds the policy, authority basis, evidence considered, revocation posture, decision result, operational effect, and review path.

Adoption guidance

Implementers SHOULD begin with the cross-repo walkthrough in docs/examples/tis-executable-artifact-walkthrough.md and the machine-readable binding in bindings/tis/tsmm-tis-binding.json.