diff --git a/chat/runtime.py b/chat/runtime.py
index eec25ced..b652ecc5 100644
--- a/chat/runtime.py
+++ b/chat/runtime.py
@@ -1195,6 +1195,53 @@ class ChatRuntime:
                 cand, source_turn_trace=trace_hash
             )
 
+    def finalize_turn_surface(
+        self,
+        surface: str,
+        articulation_surface: str | None = None,
+    ) -> None:
+        """Back-stamp the pipeline's final *served* surface onto the turn.
+
+        Weekly-audit T13 (2026-07-22): ``ChatRuntime.chat`` seals a
+        ``TurnEvent`` with the runtime-owned surface, but
+        ``CognitiveTurnPipeline`` applies the Shadow-Coherence /
+        logos-morph surface authority AFTER ``chat`` returns.  The
+        telemetry record therefore captured a surface the user never
+        saw — ``TurnEvent.surface != pipeline.run().surface`` — breaking
+        the ``warmed_session_consistency`` telemetry-consistency invariant
+        and audit/replay trust (Absolute Provenance).
+
+        The pipeline owns the final surface decision, so — exactly like
+        ``finalize_turn_trace_hash`` back-stamps the pipeline-owned
+        ``trace_hash`` — it back-stamps the resolved surface here after
+        ``resolve_surface`` + logos-morph.  Mirrors that method's
+        contract: operates on the most recent ``TurnEvent`` (main or
+        refusal-stub path), no-ops when unchanged or when no turn exists.
+
+        NOTE: the opt-in external telemetry sink (``attach_telemetry_sink``)
+        still receives the pre-override event, the same provisional-then-
+        back-stamped limitation ``finalize_turn_trace_hash`` carries today
+        (default sink is ``None`` → no-op).  Deferring the single sink
+        emission to the pipeline serve boundary — which would repair both
+        surface and ``trace_hash`` in the durable stream — is tracked as a
+        follow-up (audit ledger R7), not bolted onto this red-fix.
+        """
+        if not self.turn_log:
+            return
+        from dataclasses import replace
+
+        last_event = self.turn_log[-1]
+        updates: dict[str, str] = {}
+        if surface != last_event.surface:
+            updates["surface"] = surface
+        if (
+            articulation_surface is not None
+            and articulation_surface != last_event.articulation_surface
+        ):
+            updates["articulation_surface"] = articulation_surface
+        if updates:
+            self.turn_log[-1] = replace(last_event, **updates)
+
     def first_admitted_recognizer(self):
         if not self.config.recognition_grounded_graph:
             return None
diff --git a/core/cognition/pipeline.py b/core/cognition/pipeline.py
index ee5f8c0e..099cf75d 100644
--- a/core/cognition/pipeline.py
+++ b/core/cognition/pipeline.py
@@ -808,6 +808,16 @@ class CognitiveTurnPipeline:
         # ``source_turn_trace``.  See runtime.finalize_turn_trace_hash.
         self.runtime.finalize_turn_trace_hash(trace_hash)
 
+        # Weekly-audit T13 (2026-07-22) — back-stamp the pipeline's final
+        # *served* surface onto the same TurnEvent, sibling to the
+        # trace_hash back-stamp above.  ``resolve_surface`` + the logos-morph
+        # authority (above) can override the runtime-owned surface AFTER
+        # ``runtime.chat`` sealed the TurnEvent, so without this the
+        # telemetry record disagrees with the served bytes
+        # (warmed_session_consistency telemetry_consistency_rate < 1.0;
+        # breaks audit/replay trust — Absolute Provenance).
+        self.runtime.finalize_turn_surface(surface, articulation_surface)
+
         # B4 producer: capture the leeway the response path already decided —
         # observational only (reads the runtime's introspection-only accrual and
         # the response's reach level; never alters the surface, never gates).
diff --git a/docs/analysis/weekly-audit-2026-07-22-stragglers-todo.md b/docs/analysis/weekly-audit-2026-07-22-stragglers-todo.md
index 6f4bd038..18aaf470 100644
--- a/docs/analysis/weekly-audit-2026-07-22-stragglers-todo.md
+++ b/docs/analysis/weekly-audit-2026-07-22-stragglers-todo.md
@@ -175,7 +175,15 @@ fail-closed determinism). Execution status:
   first-match pack semantics unchanged outside the morph rule.
 - [ ] **R6** — one rule type only (`he_morph_v0.plural_abstain`);
   construct-state / prep+case / aspect deferred.
-- [ ] **T13 (main regression, serving-provenance — needs its own fix PR):
+- [ ] **R7** (opened by the T13 fix, 2026-07-22) — the opt-in telemetry SINK
+  stream (`attach_telemetry_sink`) still receives the pre-override `TurnEvent`
+  (pre-resolution surface + empty `trace_hash`) — the same provisional-then-
+  back-stamped limitation `finalize_turn_trace_hash` already carries. A single
+  deferred sink emission at the pipeline serve boundary would repair BOTH
+  surface and `trace_hash` in the durable stream. Deferred (default sink is
+  `None`, so no live consumer is affected today); own PR when a sink consumer
+  lands.
+- [x] **T13 (main regression, serving-provenance — telemetry half FIXED):
   fast lane is red on main** (was 0-red 2026-07-16):
   `tests/test_warmed_session_lane.py::TestPipelineOverrideGateInvariants::test_telemetry_consistency_rate_is_one`
   fails at 0.9444 (17/18). Verified pre-existing on unmodified main (fails
@@ -197,3 +205,21 @@ fail-closed determinism). Execution status:
   the pack surface never claimed geometric certification). Note: smoke does
   not cover this lane, and GitHub Actions are dead signals — nothing gates
   fast-lane red on main right now.
+
+  **Resolution (2026-07-22, PR `fix/telemetry-serve-boundary`):**
+  - **(1) FIXED** — `ChatRuntime.finalize_turn_surface` back-stamps the
+    pipeline's resolved surface onto `turn_log[-1]`, a sibling to
+    `finalize_turn_trace_hash`, called from `pipeline.py` immediately after
+    the trace-hash back-stamp. Lane green: `telemetry_consistency_rate`
+    0.9444 → 1.0 (10/10 warmed_session tests pass). `trace_hash` byte-identity
+    preserved — it folds the pre-decoration surface, not the served surface.
+  - **(2) OPEN — needs Shay's ruling.** Orthogonal to the red (telemetry now
+    matches whatever is served, refusal or not). Recommend **AGAINST** a
+    query-type "definitional/epistemic" classifier bypass: that fails a
+    geometric coherence gate OPEN on a lexical cue — the fail-open / cue-table
+    pattern ADR-0252 retired and INV-34 / fail-closed forbid. Principled
+    alternative: route open-geometry-but-**pack-grounded** surfaces to the
+    existing hedge-injection arm (`authoritative=False`, honestly hedged),
+    discriminated by grounding *provenance* (structural), not question type.
+    Own focused PR + real-data (not synthetic) validation.
+  - Durable-sink residual tracked as **R7** above.