diff --git a/pyproject.toml b/pyproject.toml
index 9d41e2e..9239579 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "ratatoskr"
-version = "0.15.0"
+version = "0.15.1"
 description = "Worldtree Conversation API debug TUI — multi-pane observability dashboard"
 readme = "README.md"
 requires-python = ">=3.12"
diff --git a/src/ratatoskr/sessions.py b/src/ratatoskr/sessions.py
index 00fe709..df6acd6 100644
--- a/src/ratatoskr/sessions.py
+++ b/src/ratatoskr/sessions.py
@@ -269,12 +269,21 @@ async def get_persona_state(
     resp = await client.get(f"/agents/{agent_id}/persona_state")
     if resp.status_code == 200:
         return resp.json()
-    # Discriminate the 4xx error_code sub-codes; everything else falls through.
+    # Discriminate the 4xx error_code sub-codes; everything else falls
+    # through. Worldtree returns errors as either flat `{"error_code": …}`
+    # OR FastAPI-default `{"detail": {"error_code": …}}` depending on
+    # which handler raised — unwrap both shapes (real wire observed
+    # 2026-05-28 returning the detail-nested form for auth_scope_denied
+    # from /agents/{id}/persona_state).
     try:
         err = resp.json()
-        error_code = err.get("error_code") if isinstance(err, dict) else None
     except ValueError:
-        error_code = None
+        err = None
+    error_code: str | None = None
+    if isinstance(err, dict):
+        error_code = err.get("error_code")
+        if error_code is None and isinstance(err.get("detail"), dict):
+            error_code = err["detail"].get("error_code")
     if resp.status_code == 404 and error_code == "persona_not_configured":
         raise PersonaNotConfigured(agent_id=agent_id)
     if resp.status_code == 404 and error_code == "agent_not_available":
diff --git a/tests/test_sessions.py b/tests/test_sessions.py
index a7774f7..081a373 100644
--- a/tests/test_sessions.py
+++ b/tests/test_sessions.py
@@ -665,3 +665,43 @@ class TestGetPersonaState:
             with pytest.raises(SessionApiFailed) as exc_info:
                 await get_persona_state(client, "mimir")
         assert exc_info.value.status == 500
+
+    @respx.mock
+    async def test_auth_scope_denied_detail_envelope(self) -> None:
+        """auth_scope_denied_detail_envelope [regression]: real Worldtree
+        returns `{"detail": {"error_code": "auth_scope_denied", …}}`
+        (FastAPI default), not flat `{"error_code": …}`. Smoke against
+        personal:8081 2026-05-28 surfaced this — pre-fix the response
+        fell through to SessionApiFailed(403) instead of AuthScopeDenied.
+        """
+        respx.get("https://w.example/agents/mimir/persona_state").mock(
+            return_value=httpx.Response(
+                403,
+                json={
+                    "detail": {
+                        "error_code": "auth_scope_denied",
+                        "message": "Missing required scope: persona.read",
+                    }
+                },
+            )
+        )
+        async with httpx.AsyncClient(base_url="https://w.example") as client:
+            with pytest.raises(AuthScopeDenied) as exc_info:
+                await get_persona_state(client, "mimir")
+        assert exc_info.value.scope == "persona.read"
+
+    @respx.mock
+    async def test_persona_not_configured_detail_envelope(self) -> None:
+        """persona_not_configured_detail_envelope [regression]: same
+        envelope-shape unwrap on 404 + persona_not_configured.
+        """
+        respx.get("https://w.example/agents/domari/persona_state").mock(
+            return_value=httpx.Response(
+                404,
+                json={"detail": {"error_code": "persona_not_configured"}},
+            )
+        )
+        async with httpx.AsyncClient(base_url="https://w.example") as client:
+            with pytest.raises(PersonaNotConfigured) as exc_info:
+                await get_persona_state(client, "domari")
+        assert exc_info.value.agent_id == "domari"
diff --git a/uv.lock b/uv.lock
index 8b504fd..9dff353 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1013,7 +1013,7 @@ wheels = [
 
 [[package]]
 name = "ratatoskr"
-version = "0.15.0"
+version = "0.15.1"
 source = { editable = "." }
 dependencies = [
     { name = "httpx" },