test(tools): Verify ImportError on missing mcp dependency

Adds a unit test to ensure that MCPServerAdapter raises an ImportError
when its required `mcp` package is not available.

This test uses `pytest` and `monkeypatch` to simulate the missing
dependency. It verifies the fix from the previous commit and prevents
regressions where the application might crash in non-interactive
environments.

Author: RN

tests/adapters/mcp_adapter_test.py

@@ -6,49 +6,50 @@
 from crewai_tools import MCPServerAdapter
 from crewai_tools.adapters.tool_collection import ToolCollection
 
+
 @pytest.fixture
 def echo_server_script():
     return dedent(
-        '''
+        """
         from mcp.server.fastmcp import FastMCP
 
         mcp = FastMCP("Echo Server")
 
         @mcp.tool()
         def echo_tool(text: str) -> str:
-            """Echo the input text"""
+            \"\"\"Echo the input text\"\"\"
             return f"Echo: {text}"
 
         @mcp.tool()
         def calc_tool(a: int, b: int) -> int:
-            """Calculate a + b"""
+            \"\"\"Calculate a + b\"\"\"
             return a + b
 
         mcp.run()
-        '''
+        """
     )
 
 
 @pytest.fixture
 def echo_server_sse_script():
     return dedent(
-        '''
+        """
         from mcp.server.fastmcp import FastMCP
 
         mcp = FastMCP("Echo Server", host="127.0.0.1", port=8000)
 
         @mcp.tool()
         def echo_tool(text: str) -> str:
-            """Echo the input text"""
+            \"\"\"Echo the input text\"\"\"
             return f"Echo: {text}"
 
         @mcp.tool()
         def calc_tool(a: int, b: int) -> int:
-            """Calculate a + b"""
+            \"\"\"Calculate a + b\"\"\"
             return a + b
 
         mcp.run("sse")
-        '''
+        """
     )
 
 
@@ -75,15 +76,16 @@ def echo_sse_server(echo_server_sse_script):
 
 def test_context_manager_syntax(echo_server_script):
     serverparams = StdioServerParameters(
-        command="uv", args=["run", "python", "-c", echo_server_script]
+        command="python", args=["-c", echo_server_script]
     )
     with MCPServerAdapter(serverparams) as tools:
         assert isinstance(tools, ToolCollection)
         assert len(tools) == 2
         assert tools[0].name == "echo_tool"
         assert tools[1].name == "calc_tool"
         assert tools[0].run(text="hello") == "Echo: hello"
-        assert tools[1].run(a=5, b=3) == '8'
+        assert tools[1].run(a=5, b=3) == "8"
+
 
 def test_context_manager_syntax_sse(echo_sse_server):
     sse_serverparams = echo_sse_server
@@ -92,22 +94,26 @@ def test_context_manager_syntax_sse(echo_sse_server):
         assert tools[0].name == "echo_tool"
         assert tools[1].name == "calc_tool"
         assert tools[0].run(text="hello") == "Echo: hello"
-        assert tools[1].run(a=5, b=3) == '8'
+        assert tools[1].run(a=5, b=3) == "8"
+
 
 def test_try_finally_syntax(echo_server_script):
     serverparams = StdioServerParameters(
-        command="uv", args=["run", "python", "-c", echo_server_script]
+        command="python", args=["-c", echo_server_script]
     )
+    mcp_server_adapter = None  # Define before try block
     try:
         mcp_server_adapter = MCPServerAdapter(serverparams)
         tools = mcp_server_adapter.tools
         assert len(tools) == 2
         assert tools[0].name == "echo_tool"
         assert tools[1].name == "calc_tool"
         assert tools[0].run(text="hello") == "Echo: hello"
-        assert tools[1].run(a=5, b=3) == '8'
+        assert tools[1].run(a=5, b=3) == "8"
     finally:
-        mcp_server_adapter.stop()
+        if mcp_server_adapter:
+            mcp_server_adapter.stop()
+
 
 def test_try_finally_syntax_sse(echo_sse_server):
     sse_serverparams = echo_sse_server
@@ -118,13 +124,14 @@ def test_try_finally_syntax_sse(echo_sse_server):
         assert tools[0].name == "echo_tool"
         assert tools[1].name == "calc_tool"
         assert tools[0].run(text="hello") == "Echo: hello"
-        assert tools[1].run(a=5, b=3) == '8'
+        assert tools[1].run(a=5, b=3) == "8"
     finally:
         mcp_server_adapter.stop()
 
+
 def test_context_manager_with_filtered_tools(echo_server_script):
     serverparams = StdioServerParameters(
-        command="uv", args=["run", "python", "-c", echo_server_script]
+        command="python", args=["-c", echo_server_script]
     )
     # Only select the echo_tool
     with MCPServerAdapter(serverparams, "echo_tool") as tools:
@@ -138,24 +145,27 @@ def test_context_manager_with_filtered_tools(echo_server_script):
         with pytest.raises(KeyError):
             _ = tools["calc_tool"]
 
+
 def test_context_manager_sse_with_filtered_tools(echo_sse_server):
     sse_serverparams = echo_sse_server
     # Only select the calc_tool
     with MCPServerAdapter(sse_serverparams, "calc_tool") as tools:
         assert isinstance(tools, ToolCollection)
         assert len(tools) == 1
         assert tools[0].name == "calc_tool"
-        assert tools[0].run(a=10, b=5) == '15'
+        assert tools[0].run(a=10, b=5) == "15"
         # Check that echo_tool is not present
         with pytest.raises(IndexError):
             _ = tools[1]
         with pytest.raises(KeyError):
             _ = tools["echo_tool"]
 
+
 def test_try_finally_with_filtered_tools(echo_server_script):
     serverparams = StdioServerParameters(
-        command="uv", args=["run", "python", "-c", echo_server_script]
+        command="python", args=["-c", echo_server_script]
     )
+    mcp_server_adapter = None # Define before try block
     try:
         # Select both tools but in reverse order
         mcp_server_adapter = MCPServerAdapter(serverparams, "calc_tool", "echo_tool")
@@ -166,24 +176,41 @@ def test_try_finally_with_filtered_tools(echo_server_script):
         assert tools[0].name == "calc_tool"
         assert tools[1].name == "echo_tool"
     finally:
-        mcp_server_adapter.stop()
+        if mcp_server_adapter:
+            mcp_server_adapter.stop()
+
 
 def test_filter_with_nonexistent_tool(echo_server_script):
     serverparams = StdioServerParameters(
-        command="uv", args=["run", "python", "-c", echo_server_script]
+        command="python", args=["-c", echo_server_script]
     )
     # Include a tool that doesn't exist
     with MCPServerAdapter(serverparams, "echo_tool", "nonexistent_tool") as tools:
         # Only echo_tool should be in the result
         assert len(tools) == 1
         assert tools[0].name == "echo_tool"
 
+
 def test_filter_with_only_nonexistent_tools(echo_server_script):
     serverparams = StdioServerParameters(
-        command="uv", args=["run", "python", "-c", echo_server_script]
+        command="python", args=["-c", echo_server_script]
     )
     # All requested tools don't exist
     with MCPServerAdapter(serverparams, "nonexistent1", "nonexistent2") as tools:
         # Should return an empty tool collection
         assert isinstance(tools, ToolCollection)
         assert len(tools) == 0
+
+
+def test_adapter_raises_import_error_if_mcp_is_missing(monkeypatch):
+    """
+    Tests that MCPServerAdapter raises ImportError if the mcp package is not available.
+    """
+    # 1. Simulate the condition where 'mcp' is not installed by setting the
+    #    MCP_AVAILABLE flag to False in the adapter's module.
+    monkeypatch.setattr("crewai_tools.adapters.mcp_adapter.MCP_AVAILABLE", False)
+
+    # 2. Assert that instantiating the adapter under this condition raises an
+    #    ImportError with our specific error message.
+    with pytest.raises(ImportError, match="`mcp` package not found"):
+        MCPServerAdapter(serverparams={})