diff --git a/parol6/client/async_client.py b/parol6/client/async_client.py
index ac41cd1..e48a825 100644
--- a/parol6/client/async_client.py
+++ b/parol6/client/async_client.py
@@ -1003,11 +1003,27 @@ async def shapes(self) -> ShapeWorld | None:
             return None
         return ShapeWorld(
             installation=tuple(
-                shape_from_wire(w.kind, w.params, w.pose, w.collision, w.margin, w.name)
+                shape_from_wire(
+                    w.kind,
+                    w.params,
+                    w.pose,
+                    w.collision,
+                    w.margin,
+                    w.name,
+                    w.physics,
+                )
                 for w in resp.installation
             ),
             program=tuple(
-                shape_from_wire(w.kind, w.params, w.pose, w.collision, w.margin, w.name)
+                shape_from_wire(
+                    w.kind,
+                    w.params,
+                    w.pose,
+                    w.collision,
+                    w.margin,
+                    w.name,
+                    w.physics,
+                )
                 for w in resp.program
             ),
         )
@@ -1015,6 +1031,14 @@ async def shapes(self) -> ShapeWorld | None:
     async def tcp_offset(self) -> list[float]:
         """Query current TCP offset in mm [x, y, z].
 
+        Raises ``ConnectionError`` when the controller does not answer.
+        ``[0, 0, 0]`` is a legitimate offset -- a tool deliberately cleared
+        -- so returning it as a not-answered sentinel leaves the caller
+        unable to tell "the offset is zero" from "there is no controller",
+        and a host that adopts the readback quietly erases the offset the
+        user just set. ``_request`` already retries, so reaching the end
+        here means unreachable, not one lost datagram.
+
         Category: Configuration
 
         Example:
@@ -1023,7 +1047,7 @@ async def tcp_offset(self) -> list[float]:
         resp = await self._request(TcpOffsetCmd())
         if isinstance(resp, TcpOffsetResultStruct):
             return [resp.x, resp.y, resp.z]
-        return [0.0, 0.0, 0.0]
+        raise ConnectionError("the controller did not answer tcp_offset()")
 
     async def select_profile(self, profile: str) -> int:
         """Set the motion profile (e.g. ``"TOPPRA"``).
diff --git a/parol6/protocol/wire.py b/parol6/protocol/wire.py
index 8a821f7..11bb709 100644
--- a/parol6/protocol/wire.py
+++ b/parol6/protocol/wire.py
@@ -638,7 +638,14 @@ class SetTcpOffsetCmd(
 
 
 class ShapeWire(msgspec.Struct, array_like=True, frozen=True, gc=False):
-    """One workspace shape — mirrors waldoctl ``Shape.to_wire()``."""
+    """One workspace shape — mirrors waldoctl ``Shape.to_wire()``.
+
+    ``physics`` is seventh and defaulted, which is what keeps this readable
+    both ways across the waldoctl 0.13 boundary: a peer still sending the
+    six-element form decodes with ``physics`` absent, and one sending seven
+    decodes fully. Without the field at all, every ``set_shapes`` against
+    0.13 raised ``TypeError: Extra positional arguments provided``.
+    """
 
     kind: str
     params: list[float]
@@ -646,6 +653,7 @@ class ShapeWire(msgspec.Struct, array_like=True, frozen=True, gc=False):
     collision: bool
     margin: float | None
     name: str
+    physics: list | None = None
 
 
 class SetShapesCmd(
diff --git a/pyproject.toml b/pyproject.toml
index 692601c..a2c61a8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -46,7 +46,7 @@ dependencies = [
     "psutil>=5.9",
     "msgspec>=0.18",
     "ormsgpack>=1.4.0",
-    "waldoctl @ git+https://github.com/Jepson2k/waldoctl.git@v0.12.0",
+    "waldoctl @ git+https://github.com/Jepson2k/waldoctl.git@v0.13.1",
 ]
 
 [tool.setuptools.packages.find]