docs: clarify participant access across sdk and http

docs/decisions/adrs/adr-104-runtime-control-plane-architecture.md

@@ -195,18 +195,24 @@ tenants. Multitenancy, cross-target stores, cross-run scheduling, and shared
 authorization namespaces are P3 nonclaims requiring a future ADR and explicit
 coordination, fencing, cache-coherence, and tenant-isolation contracts.
 
-Participant clients use an organizational backend boundary, not P2 or the
-in-process/store interfaces directly. P2 read roles are privileged: an identity
-allowed to retrieve a governed participant projection can also read the full
-snapshot, so a participant/audience binding does not make that credential safe
-to delegate. The backend owns organizational authentication and entitlement,
-binds each request to its selected target/run, participant, exact episode and
-audience, and releases only a permitted participant projection after the
-API-423/RUN-319 crossing. Participant-facing deployments require a configured
-crossing resolver; the legacy projection path without one carries no such
-assurance. Service credentials and raw control-plane outputs remain inside the
-trusted backend. Authentication principals do not add SDL participants or
-roles. The accepted route, authority, and deployment matrix is the
+Participant-facing clients use a trusted host application, local or
+organizational, which embeds P0/P1 SDK calls or uses the optional P2 HTTP
+adapter. For SDK use, no RAES HTTP credential exists: direct Python methods
+have no P2 role gate, `get_snapshot()` returns the full snapshot without a
+caller identity, and the host keeps the control-plane object and store private.
+For P2, deployment-configured bearer tokens or verified proxy identities are
+privileged: an identity allowed to retrieve a governed participant projection
+can also read the full snapshot, so a participant/audience binding does not
+make that P2 identity safe to delegate. The host binds its caller to the
+selected target/run, participant, exact episode, audience and operation, and
+releases only a permitted projection after the API-423/RUN-319 crossing.
+Participant-facing deployments require a configured crossing resolver; the
+current legacy projection path without one can still return a view but has no
+crossing assurance. Raw control-plane outputs stay inside the trusted host.
+An organizational host owns organizational authentication and entitlement; a
+local host applies its own caller boundary. Authentication principals do not
+add SDL participants or roles. The accepted route, authority, and deployment
+matrix is the
 [issue #1356 trust-boundary decision](../issue-1356-control-plane-participant-access-preflight.md).
 
 ### 8. Disposition of the incumbent surfaces
@@ -349,3 +355,4 @@ demonstrated its lost-update and partial-state failures.
 | 2026-09-20 | #1189 | Made profile declarations runtime-owned composition metadata, separated provider facts from guarantees, and fixed P2 and recovery-observation boundaries. |
 | 2026-09-22 | #1348 | Defined shared-runtime supervision, effect reservations, evidence-based settlement and authored recovery choices while preserving profile and implementation nonclaims. |
 | 2026-09-24 | #1356 | Bound participant clients to an organizational backend and kept privileged P2 credentials and raw control-plane outputs inside that boundary. |
+| 2026-09-25 | #1356 follow-up | Clarified SDK method access, optional P2 identity scope, host policy, and the legacy no-resolver projection gap. |

docs/decisions/adrs/adr-index.yaml

@@ -585,7 +585,7 @@ adrs:
     pin: a44acbc2db1b5349ba316ba0d09bd9b46310db016cb87937b08bc6bc107755aa
   - id: ADR-104
     path: docs/decisions/adrs/adr-104-runtime-control-plane-architecture.md
-    pin: 131d0c0923dd72ad51a9b621019b09494142b0636e7e6a5dc2d50f2f9d7766fb
+    pin: c71f377900dce99190bc1cf08d0d7c93a80fedbb6fcbb0f887cf6b5dc6b49fc6
     amendments:
       - date: 2026-09-03
         ref: "#1151"
@@ -602,6 +602,9 @@ adrs:
       - date: 2026-09-24
         ref: "#1356"
         summary: "Bound participant clients to an organizational backend and kept privileged P2 credentials and raw control-plane outputs inside that boundary."
+      - date: 2026-09-25
+        ref: "#1356 follow-up"
+        summary: "Clarified SDK method access, optional P2 identity scope, host policy, and the legacy no-resolver projection gap."
   - id: ADR-105
     path: docs/decisions/adrs/adr-105-recursive-partial-description-semantics.md
     pin: e50538c4e03d12ea92ad584322dc8618835f1724ae0086c444fba0527949a01e