Introduce a singleton

This allows the tools to populate the enums for category.

Author: pusewicz

lib/cf/mcp.rb

@@ -20,5 +20,16 @@ class Error < StandardError; end
     def self.root
       @root ||= Pathname.new(File.expand_path("../..", __dir__))
     end
+
+    module Tools
+      autoload :SearchTool, "cf/mcp/tools/search_tool"
+      autoload :ListCategory, "cf/mcp/tools/list_category"
+      autoload :GetDetails, "cf/mcp/tools/get_details"
+      autoload :FindRelated, "cf/mcp/tools/find_related"
+      autoload :ParameterSearch, "cf/mcp/tools/parameter_search"
+      autoload :MemberSearch, "cf/mcp/tools/member_search"
+      autoload :ListTopics, "cf/mcp/tools/list_topics"
+      autoload :GetTopic, "cf/mcp/tools/get_topic"
+    end
   end
 end

lib/cf/mcp/index.rb

@@ -1,11 +1,19 @@
 # frozen_string_literal: true
 
+require "singleton"
+
 module CF
   module MCP
     class Index
+      include Singleton
+
       attr_reader :items, :by_type, :by_category, :topic_references
 
       def initialize
+        reset!
+      end
+
+      def reset!
         @items = {}
         @by_type = {
           function: [],

lib/cf/mcp/index_builder.rb

@@ -18,7 +18,8 @@ def initialize(root: nil, download: false)
 
       def build
         parser = Parser.new
-        index = Index.new
+        index = Index.instance
+        index.reset!
 
         parser.parse_directory(headers_path).each do |item|
           index.add(item)

lib/cf/mcp/server.rb

@@ -1,31 +1,12 @@
 # frozen_string_literal: true
 
 require "mcp"
-require_relative "tools/search_tool"
-require_relative "tools/list_category"
-require_relative "tools/get_details"
-require_relative "tools/find_related"
-require_relative "tools/parameter_search"
-require_relative "tools/member_search"
-require_relative "tools/list_topics"
-require_relative "tools/get_topic"
 
 module CF
   module MCP
     class Server
       attr_reader :server, :index
 
-      TOOLS = [
-        Tools::SearchTool,
-        Tools::ListCategory,
-        Tools::GetDetails,
-        Tools::FindRelated,
-        Tools::ParameterSearch,
-        Tools::MemberSearch,
-        Tools::ListTopics,
-        Tools::GetTopic
-      ].freeze
-
       CORS_HEADERS = {
         "access-control-allow-origin" => "*",
         "access-control-allow-methods" => "GET, POST, DELETE, OPTIONS",
@@ -59,6 +40,7 @@ def self.build_rack_app(root: nil, download: false)
 
       def initialize(index)
         @index = index
+
         configuration = ::MCP::Configuration.new(protocol_version: PROTOCOL_VERSION)
         @server = ::MCP::Server.new(
           name: "cf-mcp",
@@ -70,7 +52,16 @@ def initialize(index)
             ::MCP::Icon.new(src: "#{WEBSITE_URL}/favicon.svg", mime_type: "image/svg+xml", sizes: ["any"]),
             ::MCP::Icon.new(src: "#{WEBSITE_URL}/favicon-96x96.png", mime_type: "image/png", sizes: ["96x96"])
           ],
-          tools: TOOLS,
+          tools: [
+            Tools::SearchTool,
+            Tools::ListCategory,
+            Tools::GetDetails,
+            Tools::FindRelated,
+            Tools::ParameterSearch,
+            Tools::MemberSearch,
+            Tools::ListTopics,
+            Tools::GetTopic
+          ],
           resources: build_topic_resources(index)
         )
         @server.server_context = {index: index}
@@ -94,7 +85,7 @@ def rack_app
 
         landing_page = build_landing_page
         index = @index
-        tools = TOOLS
+        tools = @server.tools.values
         cors_headers = CORS_HEADERS
         public_dir = PUBLIC_DIR
 

lib/cf/mcp/tools/find_related.rb

@@ -32,8 +32,7 @@ class FindRelated < ::MCP::Tool
         )
 
         def self.call(name:, server_context: {})
-          index = server_context[:index]
-          return error_response("Index not available") unless index
+          index = Index.instance
 
           item = index.find(name)
           return text_response("Not found: '#{name}'") unless item

lib/cf/mcp/tools/get_details.rb

@@ -34,8 +34,7 @@ class GetDetails < ::MCP::Tool
         NAMING_TIP = "**Tip:** Cute Framework uses `cf_` prefix for functions and `CF_` prefix for types (structs/enums)."
 
         def self.call(name:, server_context: {})
-          index = server_context[:index]
-          return error_response("Index not available") unless index
+          index = Index.instance
 
           item = index.find(name)
 

lib/cf/mcp/tools/get_topic.rb

@@ -32,8 +32,7 @@ class GetTopic < ::MCP::Tool
         )
 
         def self.call(name:, server_context: {})
-          index = server_context[:index]
-          return error_response("Index not available") unless index
+          index = Index.instance
 
           topic = index.find(name)
 

lib/cf/mcp/tools/list_category.rb

@@ -18,7 +18,7 @@ class ListCategory < ::MCP::Tool
         input_schema(
           type: "object",
           properties: {
-            category: {type: "string", description: "Category name (e.g., 'app', 'sprite', 'graphics'). Leave empty to list all categories."},
+            category: {type: "string", enum: Index.instance.categories, description: "Category name. Leave empty to list all categories."},
             type: {type: "string", enum: ["function", "struct", "enum"], description: "Optional: filter by item type"}
           }
         )
@@ -32,8 +32,7 @@ class ListCategory < ::MCP::Tool
         )
 
         def self.call(category: nil, type: nil, server_context: {})
-          index = server_context[:index]
-          return error_response("Index not available") unless index
+          index = Index.instance
 
           if category.nil? || category.empty?
             # List all categories with counts by type

lib/cf/mcp/tools/list_topics.rb

@@ -32,8 +32,7 @@ class ListTopics < ::MCP::Tool
         )
 
         def self.call(category: nil, ordered: false, server_context: {})
-          index = server_context[:index]
-          return error_response("Index not available") unless index
+          index = Index.instance
 
           topics = ordered ? index.topics_ordered : index.topics
 

lib/cf/mcp/tools/member_search.rb

@@ -33,8 +33,7 @@ class MemberSearch < ::MCP::Tool
         )
 
         def self.call(query:, limit: 20, server_context: {})
-          index = server_context[:index]
-          return error_response("Index not available") unless index
+          index = Index.instance
 
           pattern = Regexp.new(Regexp.escape(query), Regexp::IGNORECASE)
           results = []