diff --git a/tests/integrations/test_registry.py b/tests/integrations/test_registry.py
index 0110e19ec7..9bcb4b2c44 100644
--- a/tests/integrations/test_registry.py
+++ b/tests/integrations/test_registry.py
@@ -48,6 +48,11 @@ def _multi_install_safe_pairs() -> list[tuple[str, str]]:
     ]
 
 
+def _multi_install_safe_orders() -> list[list[str]]:
+    safe_keys = _multi_install_safe_keys()
+    return [safe_keys, list(reversed(safe_keys))]
+
+
 def _posix_path(value: str | None) -> str | None:
     if not value:
         return None
@@ -230,60 +235,76 @@ def test_safe_context_files_do_not_overlap_other_command_dirs(self, first, secon
             f"commands directory {_integration_commands_dir(first)!r}"
         )
 
-    @pytest.mark.parametrize(("first", "second"), _multi_install_safe_pairs())
+    @pytest.mark.parametrize(
+        "ordered_keys",
+        _multi_install_safe_orders(),
+        ids=["forward", "reverse"],
+    )
     def test_safe_integrations_have_disjoint_manifests(
         self,
         tmp_path,
-        first,
-        second,
+        ordered_keys,
     ):
-        for initial, additional in ((first, second), (second, first)):
-            project_root = tmp_path / f"project-{initial}-{additional}"
-            project_root.mkdir()
-            runner = CliRunner()
-
-            original_cwd = os.getcwd()
-            try:
-                os.chdir(project_root)
-                init_result = runner.invoke(
-                    app,
-                    [
-                        "init",
-                        "--here",
-                        "--integration",
-                        initial,
-                        "--script",
-                        "sh",
-                        "--ignore-agent-tools",
-                    ],
-                    catch_exceptions=False,
-                )
-                assert init_result.exit_code == 0, init_result.output
+        # The pairwise disjointness contract is only meaningful with at least
+        # two safe integrations. Guard so a shrunken registry fails loudly here
+        # rather than passing vacuously (or tripping over ordered_keys[0] below).
+        assert len(ordered_keys) >= 2, (
+            f"expected at least two multi-install-safe integrations, got {ordered_keys}"
+        )
 
+        project_root = tmp_path / "project"
+        project_root.mkdir()
+        runner = CliRunner()
+
+        # Install every safe integration once into a single project, then assert
+        # pairwise manifest isolation. Each safe integration writes only to its
+        # own (disjoint) directories and always records what it writes, so a
+        # manifest's contents are independent of install order and of which other
+        # integrations are co-installed. The two parametrized orders therefore
+        # produce the same manifests; their purpose is to route a different
+        # integration through the `init` path versus `integration install`
+        # (forward installs the first key via init, reverse the last).
+        original_cwd = os.getcwd()
+        try:
+            os.chdir(project_root)
+            init_result = runner.invoke(
+                app,
+                [
+                    "init",
+                    "--here",
+                    "--integration",
+                    ordered_keys[0],
+                    "--script",
+                    "sh",
+                    "--ignore-agent-tools",
+                ],
+                catch_exceptions=False,
+            )
+            assert init_result.exit_code == 0, init_result.output
+
+            for key in ordered_keys[1:]:
                 install_result = runner.invoke(
                     app,
-                    ["integration", "install", additional, "--script", "sh"],
+                    ["integration", "install", key, "--script", "sh"],
                     catch_exceptions=False,
                 )
                 assert install_result.exit_code == 0, install_result.output
-            finally:
-                os.chdir(original_cwd)
-
-            initial_manifest = json.loads(
-                (
-                    project_root / ".specify" / "integrations" / f"{initial}.manifest.json"
-                ).read_text(encoding="utf-8")
-            )
-            additional_manifest = json.loads(
-                (
-                    project_root / ".specify" / "integrations" / f"{additional}.manifest.json"
-                ).read_text(encoding="utf-8")
+        finally:
+            os.chdir(original_cwd)
+
+        integrations_dir = project_root / ".specify" / "integrations"
+        manifests = {
+            key: set(
+                json.loads(
+                    (integrations_dir / f"{key}.manifest.json").read_text(encoding="utf-8")
+                ).get("files", {})
             )
-
-            initial_files = set(initial_manifest.get("files", {}))
-            additional_files = set(additional_manifest.get("files", {}))
-
-            assert initial_files.isdisjoint(additional_files), (
-                f"{initial} and {additional} are declared multi-install safe but both manage "
-                f"these files: {sorted(initial_files & additional_files)}"
+            for key in ordered_keys
+        }
+
+        for first, second in _multi_install_safe_pairs():
+            overlap = manifests[first] & manifests[second]
+            assert not overlap, (
+                f"{first} and {second} are declared multi-install safe but both manage "
+                f"these files: {sorted(overlap)}"
             )