Merge pull request #1096 from majiayu000/fix/issue-1091-mcp-optional-import

fix: make MCP package import optional to prevent errors when not installed

Author: MervinPraison

src/praisonai-agents/praisonaiagents/mcp/mcp.py

@@ -11,8 +11,15 @@
 from typing import Any, List, Optional, Callable, Iterable, Union
 from functools import wraps, partial
 
-from mcp import ClientSession, StdioServerParameters
-from mcp.client.stdio import stdio_client
+try:
+    from mcp import ClientSession, StdioServerParameters
+    from mcp.client.stdio import stdio_client
+    MCP_AVAILABLE = True
+except ImportError:
+    MCP_AVAILABLE = False
+    ClientSession = None
+    StdioServerParameters = None
+    stdio_client = None
 
 class MCPToolRunner(threading.Thread):
     """A dedicated thread for running MCP operations."""
@@ -196,10 +203,17 @@ def __init__(self, command_or_string=None, args=None, *, command=None, timeout=6
             debug: Enable debug logging for MCP operations (default: False)
             **kwargs: Additional parameters for StdioServerParameters
         """
+        # Check if MCP is available
+        if not MCP_AVAILABLE:
+            raise ImportError(
+                "MCP (Model Context Protocol) package is not installed. "
+                "Install it with: pip install praisonaiagents[mcp]"
+            )
+
         # Handle backward compatibility with named parameter 'command'
         if command_or_string is None and command is not None:
             command_or_string = command
-        
+
         # Set up logging - default to WARNING level to hide INFO messages
         if debug:
             logging.getLogger("mcp-wrapper").setLevel(logging.DEBUG)

src/praisonai-agents/praisonaiagents/mcp/mcp_http_stream.py

@@ -16,11 +16,17 @@
 from typing import List, Dict, Any, Optional, Callable, Iterable, Union
 from urllib.parse import urlparse, urljoin
 
-from mcp import ClientSession
+try:
+    from mcp import ClientSession
+    MCP_AVAILABLE = True
+except ImportError:
+    MCP_AVAILABLE = False
+    ClientSession = None
+
 try:
     import aiohttp
 except ImportError:
-    raise ImportError("aiohttp is required for HTTP Stream transport. Install with: pip install praisonaiagents[mcp]")
+    aiohttp = None
 
 logger = logging.getLogger("mcp-http-stream")
 
@@ -507,9 +513,23 @@ def __init__(self, server_url: str, debug: bool = False, timeout: int = 60, opti
             timeout: Timeout in seconds for operations (default: 60)
             options: Additional configuration options for the transport
         """
+        # Check if MCP is available
+        if not MCP_AVAILABLE:
+            raise ImportError(
+                "MCP (Model Context Protocol) package is not installed. "
+                "Install it with: pip install praisonaiagents[mcp]"
+            )
+
+        # Check if aiohttp is available
+        if aiohttp is None:
+            raise ImportError(
+                "aiohttp is required for HTTP Stream transport. "
+                "Install it with: pip install praisonaiagents[mcp]"
+            )
+
         # Parse URL to extract base URL and endpoint
         parsed = urlparse(server_url)
-        
+
         # If the URL already has a path, use it; otherwise use default /mcp endpoint
         if parsed.path and parsed.path != '/':
             self.base_url = server_url

src/praisonai-agents/praisonaiagents/mcp/mcp_sse.py

@@ -11,8 +11,14 @@
 import json
 from typing import List, Dict, Any, Optional, Callable, Iterable
 
-from mcp import ClientSession
-from mcp.client.sse import sse_client
+try:
+    from mcp import ClientSession
+    from mcp.client.sse import sse_client
+    MCP_AVAILABLE = True
+except ImportError:
+    MCP_AVAILABLE = False
+    ClientSession = None
+    sse_client = None
 
 logger = logging.getLogger("mcp-sse")
 
@@ -169,12 +175,19 @@ def __init__(self, server_url: str, debug: bool = False, timeout: int = 60):
             debug: Whether to enable debug logging
             timeout: Timeout in seconds for operations (default: 60)
         """
+        # Check if MCP is available
+        if not MCP_AVAILABLE:
+            raise ImportError(
+                "MCP (Model Context Protocol) package is not installed. "
+                "Install it with: pip install praisonaiagents[mcp]"
+            )
+
         self.server_url = server_url
         self.debug = debug
         self.timeout = timeout
         self.session = None
         self.tools = []
-        
+
         # Set up logging
         if debug:
             logger.setLevel(logging.DEBUG)

src/praisonai-agents/tests/test_mcp_optional_import.py

@@ -0,0 +1,71 @@
+"""
+Test that MCP module imports are optional and don't break basic functionality.
+This test verifies the fix for issue #1091.
+"""
+import sys
+import pytest
+
+
+class TestMCPOptionalImport:
+    """Test that MCP is properly optional."""
+
+    def test_praisonaiagents_import_without_mcp(self):
+        """Test that praisonaiagents can be imported without mcp installed."""
+        # This should not raise any ImportError
+        import praisonaiagents
+        assert praisonaiagents is not None
+
+    def test_agent_import_without_mcp(self):
+        """Test that Agent can be imported without mcp installed."""
+        from praisonaiagents import Agent
+        assert Agent is not None
+
+    def test_mcp_lazy_loading(self):
+        """Test that MCP is lazily loaded."""
+        from praisonaiagents import MCP
+        # MCP should either be available or None (not raise ImportError on access)
+        # The actual ImportError should only be raised when trying to instantiate
+        # if mcp package is not installed
+
+    def test_mcp_module_import_no_crash(self):
+        """Test that mcp module can be imported without crashing."""
+        # This tests that the try/except in mcp.py works correctly
+        try:
+            from praisonaiagents.mcp import mcp as mcp_module
+            assert hasattr(mcp_module, 'MCP_AVAILABLE')
+        except ImportError:
+            # If import fails, it should be because of missing mcp,
+            # not because of a syntax error
+            pass
+
+    def test_mcp_sse_module_import_no_crash(self):
+        """Test that mcp_sse module can be imported without crashing."""
+        try:
+            from praisonaiagents.mcp import mcp_sse
+            assert hasattr(mcp_sse, 'MCP_AVAILABLE')
+        except ImportError:
+            pass
+
+    def test_mcp_http_stream_module_import_no_crash(self):
+        """Test that mcp_http_stream module can be imported without crashing."""
+        try:
+            from praisonaiagents.mcp import mcp_http_stream
+            assert hasattr(mcp_http_stream, 'MCP_AVAILABLE')
+        except ImportError:
+            pass
+
+    def test_basic_agent_creation_without_mcp_tools(self):
+        """Test that agents can be created without MCP tools."""
+        from praisonaiagents import Agent
+
+        # Creating an agent without MCP tools should work
+        agent = Agent(
+            name="Test Agent",
+            instructions="You are a test agent.",
+            llm="gpt-4o-mini"
+        )
+        assert agent is not None
+
+
+if __name__ == "__main__":
+    pytest.main([__file__, "-v"])