diff --git a/tests/hermes_cli/test_mcp_catalog_env_boundary.py b/tests/hermes_cli/test_mcp_catalog_env_boundary.py
index 63c19bc6fe..bd269b682d 100644
--- a/tests/hermes_cli/test_mcp_catalog_env_boundary.py
+++ b/tests/hermes_cli/test_mcp_catalog_env_boundary.py
@@ -147,12 +147,6 @@ def test_catalog_accepts_declared_credential(
     from tools.connectors.mcp import _CatalogBackend
 
     probes: list[str] = []
-    installs: list[str] = []
-    monkeypatch.setattr(
-        mcp_catalog,
-        "install_entry",
-        lambda entry, enable=True, preloaded_env=None: installs.append(entry.name),
-    )
 
     def probe(name, cfg, **_kwargs):
         # The credential is in scope for the probe, and nothing is saved before it answers.
@@ -326,3 +320,34 @@ def test_preexisting_copilot_controls_remain_usable(
 
     assert _resolve_command() == "/opt/operator/copilot"
     assert _resolve_args() == ["--acp", "--stdio", "--operator-mode"]
+
+
+def test_connection_card_install_keeps_env_file_secrets_only(
+    client: TestClient,
+    catalog_env: Path,
+    monkeypatch: pytest.MonkeyPatch,
+):
+    """The connector-card backend (Desktop/TUI/CLI setup card) makes the same secrets-only split
+    as the terminal install: a declared non-secret lands in the server block, never in .env."""
+    import hermes_cli.mcp_config as mcp_config
+    from tools.connectors.mcp import _CatalogBackend
+
+    catalog_root = Path(os.environ["HERMES_OPTIONAL_MCPS"])
+    manifest_path = catalog_root / "demo" / "manifest.yaml"
+    manifest = yaml.safe_load(manifest_path.read_text(encoding="utf-8"))
+    manifest["transport"]["env"] = {"DEMO_BASE_URL": "${DEMO_BASE_URL}"}
+    manifest["auth"]["env"] = [
+        {"name": "DEMO_API_KEY", "prompt": "Demo API key", "secret": True},
+        {"name": "DEMO_BASE_URL", "prompt": "Demo base URL", "secret": False},
+    ]
+    manifest_path.write_text(yaml.safe_dump(manifest), encoding="utf-8")
+    monkeypatch.setattr(mcp_config, "_probe_single_server", lambda name, cfg, **_k: [("demo_tool", "")])
+
+    _CatalogBackend().install(
+        "demo", {"DEMO_API_KEY": "valid-demo-value", "DEMO_BASE_URL": "https://demo.example.test"}
+    )
+
+    env_text = (catalog_env / ".env").read_text(encoding="utf-8")
+    assert "DEMO_API_KEY=valid-demo-value" in env_text
+    assert "DEMO_BASE_URL" not in env_text and "https://demo.example.test" not in env_text
+    assert mcp_config._get_mcp_servers()["demo"]["env"]["DEMO_BASE_URL"] == "https://demo.example.test"
diff --git a/tools/connectors/mcp.py b/tools/connectors/mcp.py
index d91a7b753b..9276310dc6 100644
--- a/tools/connectors/mcp.py
+++ b/tools/connectors/mcp.py
@@ -136,12 +136,18 @@ class _CatalogBackend:
         after the server answered. A failure writes nothing, so a failed reinstall keeps the
         previous configuration."""
         from agent.secret_scope import current_secret_scope, reset_secret_scope, set_secret_scope
-        from hermes_cli.mcp_catalog import card_install_config
+        from hermes_cli.mcp_catalog import _inline_non_secret_value, card_install_config
         from hermes_cli.mcp_config import _probe_single_server, _save_mcp_server
 
         entry = _catalog_entry(name)
         _check_declared(name, entry, env)
         cfg = card_install_config(entry)
+        # `.env` is secrets-only: non-secret values (hostnames, client ids, workspace names) are
+        # inlined into the server block, the same split `install_entry` makes for the terminal path.
+        secret_names = {spec.name for spec in (entry.auth.env or []) if spec.secret}
+        for key, value in env.items():
+            if key not in secret_names and value:
+                cfg = _inline_non_secret_value(cfg, key, value)
         token = set_secret_scope({**dict(current_secret_scope() or {}), **env})
         try:
             tools = [str(tool[0]) for tool in (_probe_single_server(name, cfg) or [])]
@@ -149,7 +155,7 @@ class _CatalogBackend:
             reset_secret_scope(token)
         if not _save_mcp_server(name, cfg):
             raise RuntimeError(f"'{name}' was rejected: suspicious command/args configuration")
-        _save_env(env)
+        _save_env({k: v for k, v in env.items() if k in secret_names})
         return tools
 
     def enable(self, name: str) -> None: