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_manager.py

@@ -115,14 +115,14 @@ class ConfigManager:
         # Create a deep copy to avoid modifying original
         result = copy.deepcopy(config)
         
-        # Decrypt configurations
-        if "configurations" in result and isinstance(result["configurations"], dict):
-            for name, config_data in result["configurations"].items():
-                if isinstance(config_data, dict):
-                    # Decrypt API keys for relevant providers
-                    provider = config_data.get("provider", "").lower()
-                    if provider in ["openai", "openrouter"] and "api_key" in config_data:
-                        config_data["api_key"] = self._decrypt_data(config_data["api_key"])
+         # Decrypt configurations
+         if "configurations" in result and isinstance(result["configurations"], dict):
+             for name, config_data in result["configurations"].items():
+                 if isinstance(config_data, dict):
+                     # Decrypt API keys for relevant providers
+                     provider = config_data.get("provider", "").lower()
+                     if provider in ["openai", "openrouter", "mcp"] and "api_key" in config_data:
+                         config_data["api_key"] = self._decrypt_data(config_data["api_key"])
         
         return result
     
@@ -207,7 +207,7 @@ class ConfigManager:
         
         # Validate provider
         provider = config.get("provider", "").lower()
-        valid_providers = ["openai", "ollama", "openrouter"]
+        valid_providers = ["openai", "ollama", "openrouter", "mcp"]
         
         if not provider:
             errors.append("Provider is required")
@@ -262,6 +262,35 @@ class ConfigManager:
                 if base_url.endswith("/"):
                     config["base_url"] = base_url.rstrip("/")
         
+        elif provider == "mcp":
+            server_url = config.get("server_url", "").strip()
+            if not server_url:
+                errors.append("Server URL is required for MCP provider")
+            else:
+                if not server_url.startswith(("http://", "https://")):
+                    errors.append("MCP server URL must start with http:// or https://")
+                else:
+                    # Remove trailing slash for consistency
+                    if server_url.endswith("/"):
+                        config["server_url"] = server_url.rstrip("/")
+            
+            # API key is optional for MCP (some servers might not require auth)
+            api_key = config.get("api_key", "").strip()
+            if api_key and len(api_key) < 10:
+                errors.append("MCP API key appears too short if provided")
+            
+            # Timeout is optional, but if provided must be positive integer
+            timeout = config.get("timeout")
+            if timeout is not None:
+                try:
+                    timeout_int = int(timeout)
+                    if timeout_int <= 0:
+                        errors.append("MCP timeout must be a positive integer")
+                    else:
+                        config["timeout"] = timeout_int
+                except ValueError:
+                    errors.append("MCP timeout must be a valid integer")
+        
         return len(errors) == 0, errors
     
     def get_configurations(self) -> Dict[str, Any]: