diff --git a/README.md b/README.md
index a70303f..be5c11a 100644
--- a/README.md
+++ b/README.md
@@ -129,7 +129,13 @@ Some codes raise a subclass of `DockError`, so you can catch them directly:
 `ConnectorNotConnectedError` (`connector_not_connected`, 409),
 `ConnectorAdminOnlyError` (`connector_admin_only`, 403),
 `ConnectorNotFoundError` (`connector_not_found`, 404), `ImageUnknownError`
-(`image_unknown`, 400) and `ImageUnavailableError` (`image_unavailable`, 400).
+(`image_unknown`, 400), `ImageUnavailableError` (`image_unavailable`, 400),
+`PortNotFoundError` (`port_not_found`, 404), `PortLimitReachedError`
+(`port_limit_reached`, 409) and `PortsUnavailableError` (`ports_unavailable`,
+503).
+
+Port 2222 is reserved for the dock agent and is rejected with
+`validation_error`. A dock can expose at most 10 ports.
 
 ## Configuration
 
diff --git a/src/usedock/__init__.py b/src/usedock/__init__.py
index 80ed42f..c2b59aa 100644
--- a/src/usedock/__init__.py
+++ b/src/usedock/__init__.py
@@ -6,6 +6,9 @@
     DockError,
     ImageUnavailableError,
     ImageUnknownError,
+    PortLimitReachedError,
+    PortNotFoundError,
+    PortsUnavailableError,
 )
 from .models import (
     Connector,
@@ -36,4 +39,7 @@
     "ImageUnknownError",
     "Operation",
     "Port",
+    "PortLimitReachedError",
+    "PortNotFoundError",
+    "PortsUnavailableError",
 ]
diff --git a/src/usedock/errors.py b/src/usedock/errors.py
index f6450f1..39d1126 100644
--- a/src/usedock/errors.py
+++ b/src/usedock/errors.py
@@ -39,12 +39,27 @@ class ImageUnavailableError(DockError):
     """``image_unavailable`` (400): the image is in the catalog but no host serves it right now."""
 
 
+class PortNotFoundError(DockError):
+    """``port_not_found`` (404): closing a port that is not exposed."""
+
+
+class PortLimitReachedError(DockError):
+    """``port_limit_reached`` (409): a dock already exposes the maximum of 10 ports."""
+
+
+class PortsUnavailableError(DockError):
+    """``ports_unavailable`` (503): hosted ports are not configured on this deployment."""
+
+
 _BY_CODE: Dict[str, Type[DockError]] = {
     "connector_not_connected": ConnectorNotConnectedError,
     "connector_admin_only": ConnectorAdminOnlyError,
     "connector_not_found": ConnectorNotFoundError,
     "image_unknown": ImageUnknownError,
     "image_unavailable": ImageUnavailableError,
+    "port_not_found": PortNotFoundError,
+    "port_limit_reached": PortLimitReachedError,
+    "ports_unavailable": PortsUnavailableError,
 }
 
 
diff --git a/tests/test_client.py b/tests/test_client.py
index 545ec16..abc8964 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -23,6 +23,9 @@
     DockState,
     ImageUnavailableError,
     ImageUnknownError,
+    PortLimitReachedError,
+    PortNotFoundError,
+    PortsUnavailableError,
 )
 from usedock.client import MAX_COMMAND_BYTES, shell_quote
 
@@ -642,6 +645,9 @@ def test_images_list() -> None:
         ("connector_admin_only", 403, ConnectorAdminOnlyError),
         ("image_unknown", 400, ImageUnknownError),
         ("image_unavailable", 400, ImageUnavailableError),
+        ("port_not_found", 404, PortNotFoundError),
+        ("port_limit_reached", 409, PortLimitReachedError),
+        ("ports_unavailable", 503, PortsUnavailableError),
     ],
 )
 def test_new_error_codes_raise_typed_errors(code: str, status: int, cls: type) -> None: