Core documentation

23. Model assurance modes and authority axes separately from trust labels

adr: 23
title: Model assurance modes and authority axes separately from trust labels
status: accepted
date: 2026-06-22

§Context

The original trust-tier model (first-party, certified, untrusted) collapsed identity, integrity, conformance, isolation, and authority. It also implied more safety than a deployment can enforce: a local subprocess with repository write access can bypass a proposal-only protocol.

§Decision

ASP distinguishes:

• Identity: who published or owns the provider.
• Integrity: the exact artifact/package digest or pinned version.
• Conformance: whether the provider implements the protocol correctly.
• Isolation: what the provider can read, write, execute, or transmit.
• Authority: whether policy allows its assessment to satisfy a named gate.

ASP also reports the achieved assurance mode:

• advisory: host can run/report checks but cannot enforce the boundary.
• gated: host controls a commit, merge, CI, or similar boundary.
• mediated-write: intended writes pass through the host.
• isolated: server cannot write the real worktree and has constrained data/network access.

§Consequences

• Certification never grants blocking authority automatically.
• Gate authority must be explicitly granted to a pinned provider identity for a named requirement.
• “Safe mutation” claims must name the achieved assurance mode and transaction guarantee.
• Conformance tests must include malicious, stale, missing, and degraded provider cases.