diff --git a/tests/plugins/conftest.py b/tests/plugins/conftest.py
index 5dc5ede..325b2ba 100644
--- a/tests/plugins/conftest.py
+++ b/tests/plugins/conftest.py
@@ -12,6 +12,7 @@ from __future__ import annotations
 import logging
 from pathlib import Path
 from typing import Any
+from unittest.mock import patch
 
 import pytest
 
@@ -147,6 +148,23 @@ def engine_config() -> Any:
     return EngineConfig(device="cpu")
 
 
+@pytest.fixture(autouse=True)
+def _mock_kokoro_pipeline():
+    """Prevent real KPipeline initialization during generic plugin tests.
+
+    The real KPipeline requires spacy model downloads which aren't available
+    in externally-managed environments.  Mock spacy's download and load so
+    the engine contract can be tested without heavy dependencies.
+    """
+    from unittest.mock import MagicMock
+
+    mock_nlp = MagicMock()
+
+    with patch("spacy.cli.download"), \
+         patch("spacy.load", return_value=mock_nlp):
+        yield
+
+
 @pytest.fixture
 def create_engine(loaded_plugin, host_context, engine_config):
     """Create an engine instance from a loaded plugin.
diff --git a/tests/test_kokoro_plugin.py b/tests/test_kokoro_plugin.py
index f016388..fa86776 100644
--- a/tests/test_kokoro_plugin.py
+++ b/tests/test_kokoro_plugin.py
@@ -38,8 +38,10 @@ from tests.contracts.engine_contract import EngineContractMixin
 def _kokoro_available() -> bool:
     try:
         from kokoro import KPipeline  # type: ignore[import-not-found]
+        import spacy
+        spacy.load("en_core_web_sm")
         return True
-    except ImportError:
+    except (ImportError, OSError):
         return False