Add annotated message example

Author: olaservo

everything/README.md

@@ -45,6 +45,24 @@ This MCP server attempts to exercise all the features of the MCP protocol. It is
    - No inputs required
    - Returns: JSON string of all environment variables
 
+7. `annotatedMessage`
+   - Demonstrates how annotations can be used to provide metadata about content
+   - Inputs:
+     - `messageType` (enum: "error" | "success" | "debug"): Type of message to demonstrate different annotation patterns
+     - `includeImage` (boolean, default: false): Whether to include an example image
+   - Returns: Content with varying annotations:
+     - Error messages: High priority (1.0), visible to both user and assistant
+     - Success messages: Medium priority (0.7), user-focused
+     - Debug messages: Low priority (0.3), assistant-focused
+     - Optional image: Medium priority (0.5), user-focused
+   - Example annotations:
+     ```json
+     {
+       "priority": 1.0,
+       "audience": ["user", "assistant"]
+     }
+     ```
+
 ### Resources
 
 The server provides 100 test resources in two formats:

everything/everything.ts

@@ -60,13 +60,21 @@ const EXAMPLE_COMPLETIONS = {
 
 const GetTinyImageSchema = z.object({});
 
+const AnnotatedMessageSchema = z.object({
+  messageType: z.enum(["error", "success", "debug"])
+    .describe("Type of message to demonstrate different annotation patterns"),
+  includeImage: z.boolean().default(false)
+    .describe("Whether to include an example image")
+});
+
 enum ToolName {
   ECHO = "echo",
   ADD = "add",
   LONG_RUNNING_OPERATION = "longRunningOperation",
   PRINT_ENV = "printEnv",
   SAMPLE_LLM = "sampleLLM",
   GET_TINY_IMAGE = "getTinyImage",
+  ANNOTATED_MESSAGE = "annotatedMessage",
 }
 
 enum PromptName {
@@ -329,6 +337,11 @@ export const createServer = () => {
         description: "Returns the MCP_TINY_IMAGE",
         inputSchema: zodToJsonSchema(GetTinyImageSchema) as ToolInput,
       },
+      {
+        name: ToolName.ANNOTATED_MESSAGE,
+        description: "Demonstrates how annotations can be used to provide metadata about content",
+        inputSchema: zodToJsonSchema(AnnotatedMessageSchema) as ToolInput,
+      },
     ];
 
     return { tools };
@@ -436,6 +449,57 @@ export const createServer = () => {
       };
     }
 
+    if (name === ToolName.ANNOTATED_MESSAGE) {
+      const { messageType, includeImage } = AnnotatedMessageSchema.parse(args);
+      
+      const content = [];
+
+      // Main message with different priorities/audiences based on type
+      if (messageType === "error") {
+        content.push({
+          type: "text",
+          text: "Error: Operation failed",
+          annotations: {
+            priority: 1.0, // Errors are highest priority
+            audience: ["user", "assistant"] // Both need to know about errors
+          }
+        });
+      } else if (messageType === "success") {
+        content.push({
+          type: "text",
+          text: "Operation completed successfully",
+          annotations: {
+            priority: 0.7, // Success messages are important but not critical
+            audience: ["user"] // Success mainly for user consumption
+          }
+        });
+      } else if (messageType === "debug") {
+        content.push({
+          type: "text",
+          text: "Debug: Cache hit ratio 0.95, latency 150ms",
+          annotations: {
+            priority: 0.3, // Debug info is low priority
+            audience: ["assistant"] // Technical details for assistant
+          }
+        });
+      }
+
+      // Optional image with its own annotations
+      if (includeImage) {
+        content.push({
+          type: "image",
+          data: MCP_TINY_IMAGE,
+          mimeType: "image/png",
+          annotations: {
+            priority: 0.5,
+            audience: ["user"] // Images primarily for user visualization
+          }
+        });
+      }
+
+      return { content };
+    }
+
     throw new Error(`Unknown tool: ${name}`);
   });