feat: Add MCP integration to enable tools from skills.sh and other MCP servers

- Added MCP client to discover and convert MCP tools to LangChain Tools
- Extended configuration manager to support MCP server configurations
- Updated CLI to manage MCP server configurations (list, add, remove, use)
- Integrated MCP tools into the agent's tool loading system
- Added documentation for MCP integration design

config_cli.py

@@ -42,6 +42,13 @@ def print_configurations(configs=None, title="LangCode Agent Configurations"):
             print(f"    API Key: {'Set' if config.get('api_key') else 'Not set'}")
             base_url = config.get("base_url", "https://openrouter.ai/api/v1")
             print(f"    Base URL: {base_url}")
+        elif provider == "mcp":
+            server_url = config.get("server_url", "Not set")
+            print(f"    Server URL: {server_url}")
+            api_key_status = 'Set' if config.get('api_key') else 'Not set'
+            print(f"    API Key: {api_key_status}")
+            timeout = config.get("timeout", 30)
+            print(f"    Timeout: {timeout}s")
         
         print()
 
@@ -101,12 +108,14 @@ def add_configuration_interactive():
     print("1. OpenAI")
     print("2. Ollama")
     print("3. OpenRouter")
+    print("4. MCP (Model Context Protocol)")
     
-    provider_choice = input("Enter choice (1-3): ").strip()
+    provider_choice = input("Enter choice (1-4): ").strip()
     provider_map = {
         "1": "openai",
         "2": "ollama",
-        "3": "openrouter"
+        "3": "openrouter",
+        "4": "mcp"
     }
     
     if provider_choice not in provider_map:
@@ -146,6 +155,32 @@ def add_configuration_interactive():
         if not base_url:
             base_url = "https://openrouter.ai/api/v1"
         config["base_url"] = base_url
+
+    elif provider == "mcp":
+        server_url = input("MCP server URL (e.g., https://skills.sh/mcp): ").strip()
+        if not server_url:
+            print("Error: Server URL is required for MCP")
+            return
+        config["server_url"] = server_url
+        
+        api_key = input("MCP API key (optional, press Enter to skip): ").strip()
+        if api_key:
+            config["api_key"] = api_key
+        
+        timeout_input = input(f"MCP request timeout in seconds (default: 30): ").strip()
+        if timeout_input:
+            try:
+                timeout = int(timeout_input)
+                if timeout <= 0:
+                    print("Warning: Timeout must be positive, using default 30")
+                    config["timeout"] = "30"
+                else:
+                    config["timeout"] = str(timeout)
+            except ValueError:
+                print("Warning: Invalid timeout value, using default 30")
+                config["timeout"] = "30"
+        else:
+            config["timeout"] = "30"
     
     # Ask if this should be the active configuration
     set_active = input("Set as active configuration? (y/N): ").strip().lower()