ADR-0158 - Deterministic artifact binding

Context

The checker could report a spec with no status or requirements as clean. A review could be checked against the wrong spec. Receipt links and accepted preservation failures also escaped deterministic validation. Those are wiring defects, not judgment calls.

Decision

1. Specs prove their shape. C025 requires a non-empty ID, draft or ready status, exactly one Intent and Requirements section, and at least one parsed requirement.
2. Receipt links resolve. C026 resolves explicit local Markdown evidence links carrying an E-NNN fragment against the review's directory and requires the linked file to carry the matching HTML id anchor. It does not judge evidence freshness or truth.
3. Reviews bind to specs and reviewers. Every review carries non-empty spec: and reviewer: fields. C027 requires spec: to match the packet handed through --spec; the unnumbered review shape rejects missing reviewer provenance. task: remains the optional split-slice binding checked by C020.
4. Preservation failures cannot be waived. Every Change-plan coverage row must be Supported before acceptance. Requirement waivers remain limited to Unsupported or Unverified Requirement coverage rows.
5. The contract advances to 0.20.0. C025, C026, and C027 are hard errors. Existing IDs keep their meanings.

Narrowed decisions

• ADR-0079 and ADR-0128: explicit review companions now bind both spec and task identity.
• ADR-0121 and ADR-0145: receipt links gain deterministic path and anchor validation; evidential adequacy remains human judgment.
• ADR-0152: spec shape and review wiring join the deterministic floor.
• ADR-0153: exact MCP compatibility advances to 0.20.0.
• ADR-0154: accepted preservation coverage must be fully supported.

Consequences

• Empty specs, wrong companions, dangling receipts, and waived preservation failures stop cleanly.
• The checker proves references and structure. Humans still judge evidence, independence, and risk.
• Existing reviews need one explicit spec: field.

Status

Accepted (2026-07-13). Narrows ADR-0079, ADR-0121, ADR-0128, ADR-0145, and ADR-0152 through ADR-0154.