Internal Release 0.7.0

- add support for resource templates
- improve capability negotiation on handlers
- clean up readme
- reduce default protocol version to "2024-11-05"
- address spec compliance of resources
- add debug gem to development
- alias ModelContextProtocol to MCP
- move prompt subclasses to subdir
- improve tool and prompt definition
- improve passing of server context to tools
- improve tool input schema validation

lib/model_context_protocol/methods.rb

@@ -2,13 +2,85 @@
 
 module ModelContextProtocol
   module Methods
-    RESOURCES_LIST = "resources/list"
-    RESOURCES_READ = "resources/read"
-    TOOLS_LIST = "tools/list"
-    TOOLS_CALL = "tools/call"
-    PROMPTS_LIST = "prompts/list"
-    PROMPTS_GET = "prompts/get"
     INITIALIZE = "initialize"
     PING = "ping"
+    LOGGING_SET_LEVEL = "logging/setLevel"
+
+    PROMPTS_GET = "prompts/get"
+    PROMPTS_LIST = "prompts/list"
+    COMPLETION_COMPLETE = "completion/complete"
+
+    RESOURCES_LIST = "resources/list"
+    RESOURCES_READ = "resources/read"
+    RESOURCES_TEMPLATES_LIST = "resources/templates/list"
+    RESOURCES_SUBSCRIBE = "resources/subscribe"
+    RESOURCES_UNSUBSCRIBE = "resources/unsubscribe"
+
+    TOOLS_CALL = "tools/call"
+    TOOLS_LIST = "tools/list"
+
+    SAMPLING_CREATE_MESSAGE = "sampling/createMessage"
+
+    class MissingRequiredCapabilityError < StandardError
+      attr_reader :method
+      attr_reader :capability
+
+      def initialize(method, capability)
+        super("Server does not support #{capability} (required for #{method})")
+        @method = method
+        @capability = capability
+      end
+    end
+
+    extend self
+
+    ALL_METHODS = [
+      SAMPLING_CREATE_MESSAGE,
+      INITIALIZE,
+      LOGGING_SET_LEVEL,
+      PING,
+      PROMPTS_GET,
+      PROMPTS_LIST,
+      COMPLETION_COMPLETE,
+      RESOURCES_LIST,
+      RESOURCES_READ,
+      RESOURCES_TEMPLATES_LIST,
+      RESOURCES_SUBSCRIBE,
+      RESOURCES_UNSUBSCRIBE,
+      TOOLS_CALL,
+      TOOLS_LIST,
+    ]
+
+    def ensure_capability!(method, capabilities)
+      case method
+      when PROMPTS_GET, PROMPTS_LIST, COMPLETION_COMPLETE
+        unless capabilities[:prompts]
+          raise MissingRequiredCapabilityError.new(method, :prompts)
+        end
+      when RESOURCES_LIST, RESOURCES_TEMPLATES_LIST, RESOURCES_READ, RESOURCES_SUBSCRIBE, RESOURCES_UNSUBSCRIBE
+        unless capabilities[:resources]
+          raise MissingRequiredCapabilityError.new(method, :resources)
+        end
+
+        if method == RESOURCES_SUBSCRIBE && !capabilities[:resources][:subscribe]
+          raise MissingRequiredCapabilityError.new(method, :resources_subscribe)
+        end
+      when TOOLS_CALL, TOOLS_LIST
+        unless capabilities[:tools]
+          raise MissingRequiredCapabilityError.new(method, :tools)
+        end
+      when SAMPLING_CREATE_MESSAGE
+        unless capabilities[:sampling]
+          raise MissingRequiredCapabilityError.new(method, :sampling)
+        end
+      when LOGGING_SET_LEVEL
+        # Logging is unsupported by the Server
+        unless capabilities[:logging]
+          raise MissingRequiredCapabilityError.new(method, :logging)
+        end
+      when INITIALIZE, PING
+        # No specific capability required for initialize or ping
+      end
+    end
   end
 end