fix: enforce bundle step version pins

src/specify_cli/bundler/services/primitives.py

@@ -399,6 +399,7 @@ def install(self, component: ComponentRef) -> None:
                 f"is disabled; re-run without --offline or install it first with "
                 f"'specify workflow step add {component.id}'."
             )
+        self._assert_pinned_version(component)
         from ... import workflow_step_add
 
         with _chdir(self._root):
@@ -436,6 +437,20 @@ def refresh(self, component: ComponentRef) -> None:
         finally:
             shutil.rmtree(backup_dir.parent, ignore_errors=True)
 
+    def _assert_pinned_version(self, component: ComponentRef) -> None:
+        if not component.version:
+            return
+        try:
+            from ...workflows.catalog import StepCatalog
+
+            info = StepCatalog(self._root).get_step_info(component.id)
+        except Exception:  # noqa: BLE001 - catalog unreachable: cannot enforce
+            return
+        if info:
+            _assert_pinned_version(
+                "Step", component.id, component.version, info.get("version")
+            )
+
     def remove(self, component: ComponentRef) -> None:
         from ... import workflow_step_remove
 

tests/unit/test_bundler_primitives.py

@@ -120,6 +120,26 @@ def test_workflow_version_mismatch_refuses(tmp_path: Path, monkeypatch):
         manager.install(component)
 
 
+def test_step_version_mismatch_refuses(tmp_path: Path, monkeypatch):
+    import specify_cli
+    from specify_cli.workflows.catalog import StepCatalog
+
+    monkeypatch.setattr(
+        StepCatalog, "get_step_info", lambda self, sid: {"version": "9.9.9"}
+    )
+    calls: list[str] = []
+    monkeypatch.setattr(
+        specify_cli, "workflow_step_add", lambda sid: calls.append(sid)
+    )
+
+    manager = primitive_manager("steps", tmp_path, allow_network=True)
+    component = ComponentRef(kind="steps", id="step-a", version="0.3.0")
+
+    with pytest.raises(BundlerError, match="pinned to version 0.3.0"):
+        manager.install(component)
+    assert calls == []
+
+
 def test_preset_install_preserves_explicit_zero_priority(tmp_path: Path, monkeypatch):
     import specify_cli._assets as assets