Core documentation

16. Define a native ASP outer seam, with MCP and ACP as adapters

Specification metadata

adr: 16
title: Define a native ASP outer seam, with MCP and ACP as adapters
status: accepted
date: 2026-06-21

§Context

The inner seam already lets a host run sense, judge, and act servers. Internal rollout raised a different question: should a harness talk to ASP through MCP, through ACP, or through a native ASP contract?

MCP is strong for exposing tools and read-only context. ACP is useful for editor-agent integration. Neither naturally owns gate authority, host-computed verdicts, trust enrollment, or serialized write transactions.

§Decision

ASP has a native harness-facing outer seam. MCP and ACP are adapter profiles over that seam, not the normative contract.

The native outer seam owns:

host status and composed capabilities;
changeset evaluation and host verdicts;
read-only sense queries;
proposal requests and apply transactions;
enrollment and trust visibility.

§Consequences

A blocking gate binds to asp, not to a server-specific tool or adapter.
MCP can expose ASP sense/status tools, but cannot be the source of gate authority unless it faithfully preserves the native verdict semantics.
ACP can drive editor use cases, but the host remains the policy, verdict, and apply authority.