diff --git a/plugins/nemo-deployments/src/nemo_deployments_plugin/backends/registry.py b/plugins/nemo-deployments/src/nemo_deployments_plugin/backends/registry.py
index 01820465be..4f74d7784c 100644
--- a/plugins/nemo-deployments/src/nemo_deployments_plugin/backends/registry.py
+++ b/plugins/nemo-deployments/src/nemo_deployments_plugin/backends/registry.py
@@ -31,6 +31,14 @@ class ExecutorSpec:
     config: dict[str, Any]
 
 
+@dataclass(frozen=True)
+class UnavailableExecutor:
+    """A configured executor that was skipped because its backend is unavailable."""
+
+    backend: str
+    reason: str
+
+
 class ExecutorNotFoundError(KeyError):
     """Raised when no executor matches the requested name."""
 
@@ -42,9 +50,16 @@ class UnknownBackendTypeError(KeyError):
 class ExecutorRegistry:
     """Maps executor names to configured DeploymentBackend singletons."""
 
-    def __init__(self, executors: dict[str, DeploymentBackend], *, default_executor: str | None) -> None:
+    def __init__(
+        self,
+        executors: dict[str, DeploymentBackend],
+        *,
+        default_executor: str | None,
+        unavailable: dict[str, UnavailableExecutor] | None = None,
+    ) -> None:
         self._executors = executors
         self._default_executor = default_executor
+        self._unavailable = unavailable or {}
 
     @classmethod
     def from_config(
@@ -59,6 +74,7 @@ def from_config(
         if len({spec.name for spec in specs}) != len(specs):
             raise ValueError("Duplicate executor names are not allowed.")
         executors: dict[str, DeploymentBackend] = {}
+        unavailable: dict[str, UnavailableExecutor] = {}
         try:
             for spec in specs:
                 if spec.backend not in classes:
@@ -68,10 +84,11 @@ def from_config(
                 except MissingBackendDependencyError as exc:
                     # Capability missing (optional packaging extra, unreachable Docker
                     # daemon, etc.): skip just that executor so the deployments service
-                    # can still boot. Resolving a skipped name later raises
-                    # ExecutorNotFoundError. A configured default_executor that failed
-                    # to register still fails fast below — silent clearing hid config
-                    # mistakes and made debugging harder.
+                    # can still boot. Remember it so resolving the name later explains
+                    # the missing backend instead of looking like a typo. A configured
+                    # default_executor that failed to register still fails fast below;
+                    # silent clearing hid config mistakes and made debugging harder.
+                    unavailable[spec.name] = UnavailableExecutor(backend=spec.backend, reason=str(exc))
                     logger.warning(
                         "Skipping executor '%s': backend '%s' is unavailable (%s)",
                         spec.name,
@@ -87,7 +104,7 @@ def from_config(
             for backend in executors.values():
                 backend.shutdown()
             raise
-        return cls(executors, default_executor=default_executor)
+        return cls(executors, default_executor=default_executor, unavailable=unavailable)
 
     @classmethod
     def empty(cls) -> Self:
@@ -99,6 +116,12 @@ def resolve(self, name: str | None = None) -> DeploymentBackend:
         if executor_name is None:
             raise ExecutorNotFoundError("No executor specified and no default_executor configured.")
         if executor_name not in self._executors:
+            skipped = self._unavailable.get(executor_name)
+            if skipped is not None:
+                raise ExecutorNotFoundError(
+                    f"Executor '{executor_name}' is configured but its backend "
+                    f"'{skipped.backend}' is unavailable: {skipped.reason}"
+                )
             raise ExecutorNotFoundError(f"Executor '{executor_name}' is not registered.")
         return self._executors[executor_name]
 
diff --git a/plugins/nemo-deployments/tests/unit/test_registry.py b/plugins/nemo-deployments/tests/unit/test_registry.py
index 406cc478c9..8262412e8c 100644
--- a/plugins/nemo-deployments/tests/unit/test_registry.py
+++ b/plugins/nemo-deployments/tests/unit/test_registry.py
@@ -115,10 +115,36 @@ def test_missing_executor_raises(backend_classes: dict[str, type[DeploymentBacke
         [ExecutorSpec(name="a", backend="docker", config={})],
         backend_classes=backend_classes,
     )
-    with pytest.raises(ExecutorNotFoundError):
+    with pytest.raises(ExecutorNotFoundError, match="'missing' is not registered"):
         registry.resolve("missing")
 
 
+def test_unavailable_executor_reports_distinct_error(
+    backend_classes: dict[str, type[DeploymentBackend]],
+) -> None:
+    # A configured executor whose backend was skipped must resolve to a distinct,
+    # actionable error that names the backend, not the generic 'not registered'
+    # message used for a genuinely unknown name.
+    sdk = AsyncNeMoPlatform(base_url="http://localhost:8080")
+    classes = {**backend_classes, "sandbox": _MissingDepBackend}
+    registry = ExecutorRegistry.from_config(
+        sdk,
+        [
+            ExecutorSpec(name="ok", backend="docker", config={}),
+            ExecutorSpec(name="sandbox-local", backend="sandbox", config={}),
+        ],
+        backend_classes=classes,
+    )
+    with pytest.raises(ExecutorNotFoundError) as excinfo:
+        registry.resolve("sandbox-local")
+    message = str(excinfo.value)
+    assert "is not registered" not in message
+    assert "configured but" in message
+    assert "unavailable" in message
+    assert "sandbox" in message
+    assert "openshell extra not installed" in message
+
+
 def test_unknown_backend_type_raises() -> None:
     sdk = AsyncNeMoPlatform(base_url="http://localhost:8080")
     with pytest.raises(UnknownBackendTypeError):
diff --git a/pyproject.toml b/pyproject.toml
index 80a5caff8d..274baa99a0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -213,6 +213,11 @@ core-services = [
 # Includes core services plus all application services
 functional-services = [
   { include-group = "core-services" },
+  # Ship the openshell deployment SDK in the nmp-api image only. The extra carries
+  # platform-restricted wheels (manylinux_2_39 / macOS 13 arm64) and is deliberately
+  # kept out of `enabled-plugins` so bare `uv sync` on unsupported hosts (older glibc,
+  # older macOS) does not hard-fail. The api image runs on a compatible base.
+  "nemo-deployments-plugin[openshell]",
   "nmp-studio",
   "nmp-guardrails",
   "nemo-data-designer-plugin",
diff --git a/uv.lock b/uv.lock
index 3f40ddca0a..b9c17fcc81 100644
--- a/uv.lock
+++ b/uv.lock
@@ -6452,7 +6452,7 @@ functional-services = [
     { name = "nemo-automodel-plugin", marker = "(platform_machine == 'arm64' and sys_platform == 'darwin') or (platform_machine == 'aarch64' and sys_platform == 'linux') or (platform_machine == 'x86_64' and sys_platform == 'linux')" },
     { name = "nemo-customizer-plugin", marker = "(platform_machine == 'arm64' and sys_platform == 'darwin') or (platform_machine == 'aarch64' and sys_platform == 'linux') or (platform_machine == 'x86_64' and sys_platform == 'linux')" },
     { name = "nemo-data-designer-plugin", marker = "(platform_machine == 'arm64' and sys_platform == 'darwin') or (platform_machine == 'aarch64' and sys_platform == 'linux') or (platform_machine == 'x86_64' and sys_platform == 'linux')" },
-    { name = "nemo-deployments-plugin", extra = ["docker", "k8s"], marker = "(platform_machine == 'arm64' and sys_platform == 'darwin') or (platform_machine == 'aarch64' and sys_platform == 'linux') or (platform_machine == 'x86_64' and sys_platform == 'linux')" },
+    { name = "nemo-deployments-plugin", extra = ["docker", "k8s", "openshell"], marker = "(platform_machine == 'arm64' and sys_platform == 'darwin') or (platform_machine == 'aarch64' and sys_platform == 'linux') or (platform_machine == 'x86_64' and sys_platform == 'linux')" },
     { name = "nemo-eval-author-plugin", marker = "(platform_machine == 'arm64' and sys_platform == 'darwin') or (platform_machine == 'aarch64' and sys_platform == 'linux') or (platform_machine == 'x86_64' and sys_platform == 'linux')" },
     { name = "nemo-evaluator-plugin", marker = "(platform_machine == 'arm64' and sys_platform == 'darwin') or (platform_machine == 'aarch64' and sys_platform == 'linux') or (platform_machine == 'x86_64' and sys_platform == 'linux')" },
     { name = "nemo-experimentalist-plugin", marker = "(platform_machine == 'arm64' and sys_platform == 'darwin') or (platform_machine == 'aarch64' and sys_platform == 'linux') or (platform_machine == 'x86_64' and sys_platform == 'linux')" },
@@ -6673,6 +6673,7 @@ functional-services = [
     { name = "nemo-customizer-plugin", editable = "plugins/nemo-customizer" },
     { name = "nemo-data-designer-plugin", editable = "plugins/nemo-data-designer" },
     { name = "nemo-deployments-plugin", extras = ["docker", "k8s"], editable = "plugins/nemo-deployments" },
+    { name = "nemo-deployments-plugin", extras = ["openshell"], editable = "plugins/nemo-deployments" },
     { name = "nemo-eval-author-plugin", marker = "python_full_version < '3.14'", editable = "plugins/nemo-eval-author" },
     { name = "nemo-evaluator-plugin", editable = "plugins/nemo-evaluator" },
     { name = "nemo-experimentalist-plugin", marker = "python_full_version < '3.14'", editable = "plugins/nemo-experimentalist" },