feat: add MCP tool integration via MCPO (#11)

tests/test_tools.py

@@ -14,6 +14,7 @@ from steward.config import Settings
 from steward.llm.client import LLMClient
 from steward.tools.client import (
     ToolClient,
+    _discover_mcpo_server_names,
     _operation_id,
     _resolve_operation,
     _schema_to_json_schema,
@@ -25,6 +26,22 @@ from tests.conftest import make_settings
 # Fixtures
 # ---------------------------------------------------------------------------
 
+MCPO_ROOT_SPEC: dict[str, Any] = {
+    "openapi": "3.1.0",
+    "info": {
+        "title": "MCP OpenAPI Proxy",
+        "version": "1.0",
+        "description": (
+            "Automatically generated API from MCP Tool Schemas\n\n"
+            "- **available tools**:\n"
+            "    - [github](/github/docs)\n"
+            "    - [memory](/memory/docs)\n"
+        ),
+    },
+    "paths": {},
+}
+
+
 SIMPLE_SPEC: dict[str, Any] = {
     "openapi": "3.0.0",
     "info": {"title": "Test", "version": "1.0.0"},
@@ -248,6 +265,10 @@ def test_resolve_operation_not_found():
 # ---------------------------------------------------------------------------
 
 
+def test_discover_mcpo_server_names():
+    assert _discover_mcpo_server_names(MCPO_ROOT_SPEC) == ["github", "memory"]
+
+
 @pytest.mark.asyncio
 async def test_tool_client_get_spec():
     """get_spec() fetches from /openapi.json and caches the result."""
@@ -277,6 +298,48 @@ async def test_tool_client_get_tools():
         assert tools2 is tools
 
 
+@pytest.mark.asyncio
+async def test_tool_client_get_tools_from_mcpo_subservers():
+    with respx.mock:
+        respx.get("http://tools.local/openapi.json").mock(
+            return_value=Response(200, json=MCPO_ROOT_SPEC)
+        )
+        respx.get("http://tools.local/github/openapi.json").mock(
+            return_value=Response(200, json=SIMPLE_SPEC)
+        )
+        respx.get("http://tools.local/memory/openapi.json").mock(
+            return_value=Response(200, json=SIMPLE_SPEC)
+        )
+        client = ToolClient("http://tools.local")
+        tools = await client.get_tools()
+
+    tool_names = {tool["function"]["name"] for tool in tools}
+    assert "github__list_items" in tool_names
+    assert "memory__list_items" in tool_names
+    assert len(tools) == 6
+
+
+@pytest.mark.asyncio
+async def test_tool_client_call_mcpo_namespaced_tool():
+    with respx.mock:
+        respx.get("http://tools.local/openapi.json").mock(
+            return_value=Response(200, json=MCPO_ROOT_SPEC)
+        )
+        respx.get("http://tools.local/github/openapi.json").mock(
+            return_value=Response(200, json=SIMPLE_SPEC)
+        )
+        respx.get("http://tools.local/memory/openapi.json").mock(
+            return_value=Response(200, json=SIMPLE_SPEC)
+        )
+        respx.get("http://tools.local/github/items").mock(
+            return_value=Response(200, json=[{"id": 1}])
+        )
+        client = ToolClient("http://tools.local")
+        result = await client.call("github__list_items", {"limit": 10})
+
+    assert "id" in result
+
+
 @pytest.mark.asyncio
 async def test_tool_client_call_get_with_query():
     with respx.mock: