diff --git a/tests/test_mcp_registry_opencode.py b/tests/test_mcp_registry_opencode.py
index 2340ad649..34ea814ba 100644
--- a/tests/test_mcp_registry_opencode.py
+++ b/tests/test_mcp_registry_opencode.py
@@ -419,6 +419,42 @@ def test_spec_to_entry_roundtrip() -> None:
     assert restored.env == original.env
 
 
+def test_spec_to_entry_no_env_has_no_environment_key() -> None:
+    """_spec_to_entry omits 'environment' key when spec has no env vars."""
+    from headroom.mcp_registry.base import ServerSpec
+
+    spec = ServerSpec(name="headroom", command="headroom", args=("mcp", "serve"))
+    entry = _spec_to_entry(spec)
+    assert entry["type"] == "local"
+    assert "url" not in entry
+    assert "environment" not in entry
+    assert "env" not in entry
+
+
+def test_entry_to_spec_reads_environment_field() -> None:
+    """_entry_to_spec reads the 'environment' field (not legacy 'env')."""
+    entry = {
+        "type": "local",
+        "command": ["headroom", "mcp", "serve"],
+        "environment": {"HEADROOM_PROXY_URL": "http://127.0.0.1:8787"},
+        "enabled": True,
+    }
+    spec = _entry_to_spec("headroom", entry)
+    assert spec.env == {"HEADROOM_PROXY_URL": "http://127.0.0.1:8787"}
+
+
+def test_entry_to_spec_falls_back_to_legacy_env_field() -> None:
+    """_entry_to_spec falls back to 'env' when 'environment' is absent."""
+    entry = {
+        "type": "local",
+        "command": ["headroom", "mcp", "serve"],
+        "env": {"LEGACY_KEY": "value"},
+        "enabled": True,
+    }
+    spec = _entry_to_spec("headroom", entry)
+    assert spec.env == {"LEGACY_KEY": "value"}
+
+
 def test_diff_specs_all_fields() -> None:
     """_diff_specs reports differences in all fields."""
     from headroom.mcp_registry.base import ServerSpec