diff --git a/README.md b/README.md
index 6c100735..3ab5a898 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,7 @@
   - [Resources](#resources)
   - [Tools](#tools)
   - [Prompts](#prompts)
+  - [Completions](#completions)
 - [Running Your Server](#running-your-server)
   - [stdio](#stdio)
   - [Streamable HTTP](#streamable-http)
@@ -54,22 +55,30 @@ import { z } from "zod";
 
 // Create an MCP server
 const server = new McpServer({
-  name: "Demo",
+  name: "demo-server",
   version: "1.0.0"
 });
 
 // Add an addition tool
-server.tool("add",
-  { a: z.number(), b: z.number() },
+server.registerTool("add",
+  {
+    title: "Addition Tool",
+    description: "Add two numbers",
+    inputSchema: { a: z.number(), b: z.number() }
+  },
   async ({ a, b }) => ({
     content: [{ type: "text", text: String(a + b) }]
   })
 );
 
 // Add a dynamic greeting resource
-server.resource(
+server.registerResource(
   "greeting",
   new ResourceTemplate("greeting://{name}", { list: undefined }),
+  { 
+    title: "Greeting Resource",      // Display name for UI
+    description: "Dynamic greeting generator"
+  },
   async (uri, { name }) => ({
     contents: [{
       uri: uri.href,
@@ -100,7 +109,7 @@ The McpServer is your core interface to the MCP protocol. It handles connection
 
 ```typescript
 const server = new McpServer({
-  name: "My App",
+  name: "my-app",
   version: "1.0.0"
 });
 ```
@@ -111,9 +120,14 @@ Resources are how you expose data to LLMs. They're similar to GET endpoints in a
 
 ```typescript
 // Static resource
-server.resource(
+server.registerResource(
   "config",
   "config://app",
+  {
+    title: "Application Config",
+    description: "Application configuration data",
+    mimeType: "text/plain"
+  },
   async (uri) => ({
     contents: [{
       uri: uri.href,
@@ -123,9 +137,13 @@ server.resource(
 );
 
 // Dynamic resource with parameters
-server.resource(
+server.registerResource(
   "user-profile",
   new ResourceTemplate("users://{userId}/profile", { list: undefined }),
+  {
+    title: "User Profile",
+    description: "User profile information"
+  },
   async (uri, { userId }) => ({
     contents: [{
       uri: uri.href,
@@ -133,6 +151,33 @@ server.resource(
     }]
   })
 );
+
+// Resource with context-aware completion
+server.registerResource(
+  "repository",
+  new ResourceTemplate("github://repos/{owner}/{repo}", {
+    list: undefined,
+    complete: {
+      // Provide intelligent completions based on previously resolved parameters
+      repo: (value, context) => {
+        if (context?.arguments?.["owner"] === "org1") {
+          return ["project1", "project2", "project3"].filter(r => r.startsWith(value));
+        }
+        return ["default-repo"].filter(r => r.startsWith(value));
+      }
+    }
+  }),
+  {
+    title: "GitHub Repository",
+    description: "Repository information"
+  },
+  async (uri, { owner, repo }) => ({
+    contents: [{
+      uri: uri.href,
+      text: `Repository: ${owner}/${repo}`
+    }]
+  })
+);
 ```
 
 ### Tools
@@ -141,11 +186,15 @@ Tools let LLMs take actions through your server. Unlike resources, tools are exp
 
 ```typescript
 // Simple tool with parameters
-server.tool(
+server.registerTool(
   "calculate-bmi",
   {
-    weightKg: z.number(),
-    heightM: z.number()
+    title: "BMI Calculator",
+    description: "Calculate Body Mass Index",
+    inputSchema: {
+      weightKg: z.number(),
+      heightM: z.number()
+    }
   },
   async ({ weightKg, heightM }) => ({
     content: [{
@@ -156,9 +205,13 @@ server.tool(
 );
 
 // Async tool with external API call
-server.tool(
+server.registerTool(
   "fetch-weather",
-  { city: z.string() },
+  {
+    title: "Weather Fetcher",
+    description: "Get weather data for a city",
+    inputSchema: { city: z.string() }
+  },
   async ({ city }) => {
     const response = await fetch(`https://api.weather.com/${city}`);
     const data = await response.text();
@@ -167,16 +220,56 @@ server.tool(
     };
   }
 );
+
+// Tool that returns ResourceLinks
+server.registerTool(
+  "list-files",
+  {
+    title: "List Files",
+    description: "List project files",
+    inputSchema: { pattern: z.string() }
+  },
+  async ({ pattern }) => ({
+    content: [
+      { type: "text", text: `Found files matching "${pattern}":` },
+      // ResourceLinks let tools return references without file content
+      {
+        type: "resource_link",
+        uri: "file:///project/README.md",
+        name: "README.md",
+        mimeType: "text/markdown",
+        description: 'A README file'
+      },
+      {
+        type: "resource_link",
+        uri: "file:///project/src/index.ts",
+        name: "index.ts",
+        mimeType: "text/typescript",
+        description: 'An index file'
+      }
+    ]
+  })
+);
 ```
 
+#### ResourceLinks
+
+Tools can return `ResourceLink` objects to reference resources without embedding their full content. This is essential for performance when dealing with large files or many resources - clients can then selectively read only the resources they need using the provided URIs.
+
 ### Prompts
 
 Prompts are reusable templates that help LLMs interact with your server effectively:
 
 ```typescript
-server.prompt(
+import { completable } from "@modelcontextprotocol/sdk/server/completable.js";
+
+server.registerPrompt(
   "review-code",
-  { code: z.string() },
+  {
+    title: "Code Review",
+    description: "Review code for best practices and potential issues",
+    argsSchema: { code: z.string() }
+  },
   ({ code }) => ({
     messages: [{
       role: "user",
@@ -187,6 +280,106 @@ server.prompt(
     }]
   })
 );
+
+// Prompt with context-aware completion
+server.registerPrompt(
+  "team-greeting",
+  {
+    title: "Team Greeting",
+    description: "Generate a greeting for team members",
+    argsSchema: {
+      department: completable(z.string(), (value) => {
+        // Department suggestions
+        return ["engineering", "sales", "marketing", "support"].filter(d => d.startsWith(value));
+      }),
+      name: completable(z.string(), (value, context) => {
+        // Name suggestions based on selected department
+        const department = context?.arguments?.["department"];
+        if (department === "engineering") {
+          return ["Alice", "Bob", "Charlie"].filter(n => n.startsWith(value));
+        } else if (department === "sales") {
+          return ["David", "Eve", "Frank"].filter(n => n.startsWith(value));
+        } else if (department === "marketing") {
+          return ["Grace", "Henry", "Iris"].filter(n => n.startsWith(value));
+        }
+        return ["Guest"].filter(n => n.startsWith(value));
+      })
+    }
+  },
+  ({ department, name }) => ({
+    messages: [{
+      role: "assistant",
+      content: {
+        type: "text",
+        text: `Hello ${name}, welcome to the ${department} team!`
+      }
+    }]
+  })
+);
+```
+
+### Completions
+
+MCP supports argument completions to help users fill in prompt arguments and resource template parameters. See the examples above for [resource completions](#resources) and [prompt completions](#prompts).
+
+#### Client Usage
+
+```typescript
+// Request completions for any argument
+const result = await client.complete({
+  ref: {
+    type: "ref/prompt",  // or "ref/resource"
+    name: "example"      // or uri: "template://..."
+  },
+  argument: {
+    name: "argumentName",
+    value: "partial"     // What the user has typed so far
+  },
+  context: {             // Optional: Include previously resolved arguments
+    arguments: {
+      previousArg: "value"
+    }
+  }
+});
+
+```
+
+### Display Names and Metadata
+
+All resources, tools, and prompts support an optional `title` field for better UI presentation. The `title` is used as a display name, while `name` remains the unique identifier.
+
+**Note:** The `register*` methods (`registerTool`, `registerPrompt`, `registerResource`) are the recommended approach for new code. The older methods (`tool`, `prompt`, `resource`) remain available for backwards compatibility.
+
+#### Title Precedence for Tools
+
+For tools specifically, there are two ways to specify a title:
+- `title` field in the tool configuration
+- `annotations.title` field (when using the older `tool()` method with annotations)
+
+The precedence order is: `title` → `annotations.title` → `name`
+
+```typescript
+// Using registerTool (recommended)
+server.registerTool("my_tool", {
+  title: "My Tool",              // This title takes precedence
+  annotations: {
+    title: "Annotation Title"    // This is ignored if title is set
+  }
+}, handler);
+
+// Using tool with annotations (older API)
+server.tool("my_tool", "description", {
+  title: "Annotation Title"      // This is used as title
+}, handler);
+```
+
+When building clients, use the provided utility to get the appropriate display name:
+
+```typescript
+import { getDisplayName } from "@modelcontextprotocol/sdk/shared/metadataUtils.js";
+
+// Automatically handles the precedence: title → annotations.title → name
+const displayName = getDisplayName(tool);
 ```
 
 ## Running Your Server
@@ -401,13 +594,17 @@ import { McpServer, ResourceTemplate } from "@modelcontextprotocol/sdk/server/mc
 import { z } from "zod";
 
 const server = new McpServer({
-  name: "Echo",
+  name: "echo-server",
   version: "1.0.0"
 });
 
-server.resource(
+server.registerResource(
   "echo",
   new ResourceTemplate("echo://{message}", { list: undefined }),
+  {
+    title: "Echo Resource",
+    description: "Echoes back messages as resources"
+  },
   async (uri, { message }) => ({
     contents: [{
       uri: uri.href,
@@ -416,17 +613,25 @@ server.resource(
   })
 );
 
-server.tool(
+server.registerTool(
   "echo",
-  { message: z.string() },
+  {
+    title: "Echo Tool",
+    description: "Echoes back the provided message",
+    inputSchema: { message: z.string() }
+  },
   async ({ message }) => ({
     content: [{ type: "text", text: `Tool echo: ${message}` }]
   })
 );
 
-server.prompt(
+server.registerPrompt(
   "echo",
-  { message: z.string() },
+  {
+    title: "Echo Prompt",
+    description: "Creates a prompt to process a message",
+    argsSchema: { message: z.string() }
+  },
   ({ message }) => ({
     messages: [{
       role: "user",
@@ -450,7 +655,7 @@ import { promisify } from "util";
 import { z } from "zod";
 
 const server = new McpServer({
-  name: "SQLite Explorer",
+  name: "sqlite-explorer",
   version: "1.0.0"
 });
 
@@ -463,9 +668,14 @@ const getDb = () => {
   };
 };
 
-server.resource(
+server.registerResource(
   "schema",
   "schema://main",
+  {
+    title: "Database Schema",
+    description: "SQLite database schema",
+    mimeType: "text/plain"
+  },
   async (uri) => {
     const db = getDb();
     try {
@@ -484,9 +694,13 @@ server.resource(
   }
 );
 
-server.tool(
+server.registerTool(
   "query",
-  { sql: z.string() },
+  {
+    title: "SQL Query",
+    description: "Execute SQL queries on the database",
+    inputSchema: { sql: z.string() }
+  },
   async ({ sql }) => {
     const db = getDb();
     try {
@@ -785,6 +999,7 @@ const result = await client.callTool({
     arg1: "value"
   }
 });
+
 ```
 
 ### Proxy Authorization Requests Upstream
diff --git a/package.json b/package.json
index 764ce2cb..6b184f31 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@modelcontextprotocol/sdk",
-  "version": "1.12.2",
+  "version": "1.12.3",
   "description": "Model Context Protocol implementation for TypeScript",
   "license": "MIT",
   "author": "Anthropic, PBC (https://anthropic.com)",
diff --git a/src/client/index.ts b/src/client/index.ts
index 53ef8c52..f3d440b9 100644
--- a/src/client/index.ts
+++ b/src/client/index.ts
@@ -165,6 +165,10 @@ export class Client<
 
       this._serverCapabilities = result.capabilities;
       this._serverVersion = result.serverInfo;
+      // HTTP transports must set the protocol version in each header after initialization.
+      if (transport.setProtocolVersion) {
+        transport.setProtocolVersion(result.protocolVersion);
+      }
 
       this._instructions = result.instructions;
 
diff --git a/src/client/sse.ts b/src/client/sse.ts
index 7939e8cb..5aa99abb 100644
--- a/src/client/sse.ts
+++ b/src/client/sse.ts
@@ -62,6 +62,7 @@ export class SSEClientTransport implements Transport {
   private _eventSourceInit?: EventSourceInit;
   private _requestInit?: RequestInit;
   private _authProvider?: OAuthClientProvider;
+  private _protocolVersion?: string;
 
   onclose?: () => void;
   onerror?: (error: Error) => void;
@@ -99,13 +100,18 @@ export class SSEClientTransport implements Transport {
   }
 
   private async _commonHeaders(): Promise<HeadersInit> {
-    const headers: HeadersInit = { ...this._requestInit?.headers };
+    const headers = {
+      ...this._requestInit?.headers,
+    } as HeadersInit & Record<string, string>;
     if (this._authProvider) {
       const tokens = await this._authProvider.tokens();
       if (tokens) {
-        (headers as Record<string, string>)["Authorization"] = `Bearer ${tokens.access_token}`;
+        headers["Authorization"] = `Bearer ${tokens.access_token}`;
       }
     }
+    if (this._protocolVersion) {
+      headers["mcp-protocol-version"] = this._protocolVersion;
+    }
 
     return headers;
   }
@@ -214,7 +220,7 @@ export class SSEClientTransport implements Transport {
 
     try {
       const commonHeaders = await this._commonHeaders();
-      const headers = new Headers({ ...commonHeaders, ...this._requestInit?.headers });
+      const headers = new Headers(commonHeaders);
       headers.set("content-type", "application/json");
       const init = {
         ...this._requestInit,
@@ -249,4 +255,8 @@ export class SSEClientTransport implements Transport {
       throw error;
     }
   }
+
+  setProtocolVersion(version: string): void {
+    this._protocolVersion = version;
+  }
 }
diff --git a/src/client/streamableHttp.ts b/src/client/streamableHttp.ts
index 1bcfbb2d..4117bb1b 100644
--- a/src/client/streamableHttp.ts
+++ b/src/client/streamableHttp.ts
@@ -124,6 +124,7 @@ export class StreamableHTTPClientTransport implements Transport {
   private _authProvider?: OAuthClientProvider;
   private _sessionId?: string;
   private _reconnectionOptions: StreamableHTTPReconnectionOptions;
+  private _protocolVersion?: string;
 
   onclose?: () => void;
   onerror?: (error: Error) => void;
@@ -162,7 +163,7 @@ export class StreamableHTTPClientTransport implements Transport {
   }
 
   private async _commonHeaders(): Promise<Headers> {
-    const headers: HeadersInit = {};
+    const headers: HeadersInit & Record<string, string> = {};
     if (this._authProvider) {
       const tokens = await this._authProvider.tokens();
       if (tokens) {
@@ -173,6 +174,9 @@ export class StreamableHTTPClientTransport implements Transport {
     if (this._sessionId) {
       headers["mcp-session-id"] = this._sessionId;
     }
+    if (this._protocolVersion) {
+      headers["mcp-protocol-version"] = this._protocolVersion;
+    }
 
     return new Headers(
       { ...headers, ...this._requestInit?.headers }
@@ -516,4 +520,11 @@ export class StreamableHTTPClientTransport implements Transport {
       throw error;
     }
   }
+
+  setProtocolVersion(version: string): void {
+    this._protocolVersion = version;
+  }
+  get protocolVersion(): string | undefined {
+    return this._protocolVersion;
+  }
 }
diff --git a/src/examples/client/simpleStreamableHttp.ts b/src/examples/client/simpleStreamableHttp.ts
index 8d143a5a..ddb27419 100644
--- a/src/examples/client/simpleStreamableHttp.ts
+++ b/src/examples/client/simpleStreamableHttp.ts
@@ -15,7 +15,11 @@ import {
   LoggingMessageNotificationSchema,
   ResourceListChangedNotificationSchema,
   ElicitRequestSchema,
+  ResourceLink,
+  ReadResourceRequest,
+  ReadResourceResultSchema,
 } from '../../types.js';
+import { getDisplayName } from '../../shared/metadataUtils.js';
 import Ajv from "ajv";
 
 // Create readline interface for user input
@@ -62,6 +66,7 @@ function printHelp(): void {
   console.log('  list-prompts               - List available prompts');
   console.log('  get-prompt [name] [args]   - Get a prompt with optional JSON arguments');
   console.log('  list-resources             - List available resources');
+  console.log('  read-resource <uri>        - Read a specific resource by URI');
   console.log('  help                       - Show this help');
   console.log('  quit                       - Exit the program');
 }
@@ -161,6 +166,14 @@ function commandLoop(): void {
           await listResources();
           break;
 
+        case 'read-resource':
+          if (args.length < 2) {
+            console.log('Usage: read-resource <uri>');
+          } else {
+            await readResource(args[1]);
+          }
+          break;
+
         case 'help':
           printHelp();
           break;
@@ -521,7 +534,7 @@ async function listTools(): Promise<void> {
       console.log('  No tools available');
     } else {
       for (const tool of toolsResult.tools) {
-        console.log(`  - ${tool.name}: ${tool.description}`);
+        console.log(`  - id: ${tool.name}, name: ${getDisplayName(tool)}, description: ${tool.description}`);
       }
     }
   } catch (error) {
@@ -548,13 +561,37 @@ async function callTool(name: string, args: Record<string, unknown>): Promise<vo
     const result = await client.request(request, CallToolResultSchema);
 
     console.log('Tool result:');
+    const resourceLinks: ResourceLink[] = [];
+
     result.content.forEach(item => {
       if (item.type === 'text') {
         console.log(`  ${item.text}`);
+      } else if (item.type === 'resource_link') {
+        const resourceLink = item as ResourceLink;
+        resourceLinks.push(resourceLink);
+        console.log(`  📁 Resource Link: ${resourceLink.name}`);
+        console.log(`     URI: ${resourceLink.uri}`);
+        if (resourceLink.mimeType) {
+          console.log(`     Type: ${resourceLink.mimeType}`);
+        }
+        if (resourceLink.description) {
+          console.log(`     Description: ${resourceLink.description}`);
+        }
+      } else if (item.type === 'resource') {
+        console.log(`  [Embedded Resource: ${item.resource.uri}]`);
+      } else if (item.type === 'image') {
+        console.log(`  [Image: ${item.mimeType}]`);
+      } else if (item.type === 'audio') {
+        console.log(`  [Audio: ${item.mimeType}]`);
       } else {
-        console.log(`  ${item.type} content:`, item);
+        console.log(`  [Unknown content type]:`, item);
       }
     });
+
+    // Offer to read resource links
+    if (resourceLinks.length > 0) {
+      console.log(`\nFound ${resourceLinks.length} resource link(s). Use 'read-resource <uri>' to read their content.`);
+    }
   } catch (error) {
     console.log(`Error calling tool ${name}: ${error}`);
   }
@@ -589,7 +626,7 @@ async function runNotificationsToolWithResumability(interval: number, count: num
   try {
     console.log(`Starting notification stream with resumability: interval=${interval}ms, count=${count || 'unlimited'}`);
     console.log(`Using resumption token: ${notificationsToolLastEventId || 'none'}`);
-    
+
     const request: CallToolRequest = {
       method: 'tools/call',
       params: {
@@ -602,7 +639,7 @@ async function runNotificationsToolWithResumability(interval: number, count: num
       notificationsToolLastEventId = event;
       console.log(`Updated resumption token: ${event}`);
     };
-    
+
     const result = await client.request(request, CallToolResultSchema, {
       resumptionToken: notificationsToolLastEventId,
       onresumptiontoken: onLastEventIdUpdate
@@ -638,7 +675,7 @@ async function listPrompts(): Promise<void> {
       console.log('  No prompts available');
     } else {
       for (const prompt of promptsResult.prompts) {
-        console.log(`  - ${prompt.name}: ${prompt.description}`);
+        console.log(`  - id: ${prompt.name}, name: ${getDisplayName(prompt)}, description: ${prompt.description}`);
       }
     }
   } catch (error) {
@@ -689,7 +726,7 @@ async function listResources(): Promise<void> {
       console.log('  No resources available');
     } else {
       for (const resource of resourcesResult.resources) {
-        console.log(`  - ${resource.name}: ${resource.uri}`);
+        console.log(`  - id: ${resource.name}, name: ${getDisplayName(resource)}, description: ${resource.uri}`);
       }
     }
   } catch (error) {
@@ -697,6 +734,42 @@ async function listResources(): Promise<void> {
   }
 }
 
+async function readResource(uri: string): Promise<void> {
+  if (!client) {
+    console.log('Not connected to server.');
+    return;
+  }
+
+  try {
+    const request: ReadResourceRequest = {
+      method: 'resources/read',
+      params: { uri }
+    };
+
+    console.log(`Reading resource: ${uri}`);
+    const result = await client.request(request, ReadResourceResultSchema);
+
+    console.log('Resource contents:');
+    for (const content of result.contents) {
+      console.log(`  URI: ${content.uri}`);
+      if (content.mimeType) {
+        console.log(`  Type: ${content.mimeType}`);
+      }
+
+      if ('text' in content && typeof content.text === 'string') {
+        console.log('  Content:');
+        console.log('  ---');
+        console.log(content.text.split('\n').map((line: string) => '  ' + line).join('\n'));
+        console.log('  ---');
+      } else if ('blob' in content && typeof content.blob === 'string') {
+        console.log(`  [Binary data: ${content.blob.length} bytes]`);
+      }
+    }
+  } catch (error) {
+    console.log(`Error reading resource ${uri}: ${error}`);
+  }
+}
+
 async function cleanup(): Promise<void> {
   if (client && transport) {
     try {
diff --git a/src/examples/server/simpleStreamableHttp.ts b/src/examples/server/simpleStreamableHttp.ts
index 4ef50446..52c49caf 100644
--- a/src/examples/server/simpleStreamableHttp.ts
+++ b/src/examples/server/simpleStreamableHttp.ts
@@ -5,7 +5,7 @@ import { McpServer } from '../../server/mcp.js';
 import { StreamableHTTPServerTransport } from '../../server/streamableHttp.js';
 import { getOAuthProtectedResourceMetadataUrl, mcpAuthMetadataRouter } from '../../server/auth/router.js';
 import { requireBearerAuth } from '../../server/auth/middleware/bearerAuth.js';
-import { CallToolResult, GetPromptResult, isInitializeRequest, PrimitiveSchemaDefinition, ReadResourceResult } from '../../types.js';
+import { CallToolResult, GetPromptResult, isInitializeRequest, PrimitiveSchemaDefinition, ReadResourceResult, ResourceLink } from '../../types.js';
 import { InMemoryEventStore } from '../shared/inMemoryEventStore.js';
 import { setupAuthServer } from './demoInMemoryOAuthProvider.js';
 import { OAuthMetadata } from 'src/shared/auth.js';
@@ -17,15 +17,18 @@ const useOAuth = process.argv.includes('--oauth');
 const getServer = () => {
   const server = new McpServer({
     name: 'simple-streamable-http-server',
-    version: '1.0.0',
+    version: '1.0.0'
   }, { capabilities: { logging: {} } });
 
   // Register a simple tool that returns a greeting
-  server.tool(
+  server.registerTool(
     'greet',
-    'A simple greeting tool',
     {
-      name: z.string().describe('Name to greet'),
+      title: 'Greeting Tool',  // Display name for UI
+      description: 'A simple greeting tool',
+      inputSchema: {
+        name: z.string().describe('Name to greet'),
+      },
     },
     async ({ name }): Promise<CallToolResult> => {
       return {
@@ -83,7 +86,6 @@ const getServer = () => {
       };
     }
   );
-
   // Register a tool that demonstrates elicitation (user input collection)
   // This creates a closure that captures the server instance
   server.tool(
@@ -234,13 +236,15 @@ const getServer = () => {
     }
   );
 
-
-  // Register a simple prompt
-  server.prompt(
+  // Register a simple prompt with title
+  server.registerPrompt(
     'greeting-template',
-    'A simple greeting prompt template',
     {
-      name: z.string().describe('Name to include in greeting'),
+      title: 'Greeting Template',  // Display name for UI
+      description: 'A simple greeting prompt template',
+      argsSchema: {
+        name: z.string().describe('Name to include in greeting'),
+      },
     },
     async ({ name }): Promise<GetPromptResult> => {
       return {
@@ -299,10 +303,14 @@ const getServer = () => {
   );
 
   // Create a simple resource at a fixed URI
-  server.resource(
+  server.registerResource(
     'greeting-resource',
     'https://example.com/greetings/default',
-    { mimeType: 'text/plain' },
+    {
+      title: 'Default Greeting',  // Display name for UI
+      description: 'A simple greeting resource',
+      mimeType: 'text/plain'
+    },
     async (): Promise<ReadResourceResult> => {
       return {
         contents: [
@@ -314,6 +322,99 @@ const getServer = () => {
       };
     }
   );
+
+  // Create additional resources for ResourceLink demonstration
+  server.registerResource(
+    'example-file-1',
+    'file:///example/file1.txt',
+    {
+      title: 'Example File 1',
+      description: 'First example file for ResourceLink demonstration',
+      mimeType: 'text/plain'
+    },
+    async (): Promise<ReadResourceResult> => {
+      return {
+        contents: [
+          {
+            uri: 'file:///example/file1.txt',
+            text: 'This is the content of file 1',
+          },
+        ],
+      };
+    }
+  );
+
+  server.registerResource(
+    'example-file-2',
+    'file:///example/file2.txt',
+    {
+      title: 'Example File 2',
+      description: 'Second example file for ResourceLink demonstration',
+      mimeType: 'text/plain'
+    },
+    async (): Promise<ReadResourceResult> => {
+      return {
+        contents: [
+          {
+            uri: 'file:///example/file2.txt',
+            text: 'This is the content of file 2',
+          },
+        ],
+      };
+    }
+  );
+
+  // Register a tool that returns ResourceLinks
+  server.registerTool(
+    'list-files',
+    {
+      title: 'List Files with ResourceLinks',
+      description: 'Returns a list of files as ResourceLinks without embedding their content',
+      inputSchema: {
+        includeDescriptions: z.boolean().optional().describe('Whether to include descriptions in the resource links'),
+      },
+    },
+    async ({ includeDescriptions = true }): Promise<CallToolResult> => {
+      const resourceLinks: ResourceLink[] = [
+        {
+          type: 'resource_link',
+          uri: 'https://example.com/greetings/default',
+          name: 'Default Greeting',
+          mimeType: 'text/plain',
+          ...(includeDescriptions && { description: 'A simple greeting resource' })
+        },
+        {
+          type: 'resource_link',
+          uri: 'file:///example/file1.txt',
+          name: 'Example File 1',
+          mimeType: 'text/plain',
+          ...(includeDescriptions && { description: 'First example file for ResourceLink demonstration' })
+        },
+        {
+          type: 'resource_link',
+          uri: 'file:///example/file2.txt',
+          name: 'Example File 2',
+          mimeType: 'text/plain',
+          ...(includeDescriptions && { description: 'Second example file for ResourceLink demonstration' })
+        }
+      ];
+
+      return {
+        content: [
+          {
+            type: 'text',
+            text: 'Here are the available files as resource links:',
+          },
+          ...resourceLinks,
+          {
+            type: 'text',
+            text: '\nYou can read any of these resources using their URI.',
+          }
+        ],
+      };
+    }
+  );
+
   return server;
 };
 
diff --git a/src/integration-tests/stateManagementStreamableHttp.test.ts b/src/integration-tests/stateManagementStreamableHttp.test.ts
index b7ff17e6..d12a4f99 100644
--- a/src/integration-tests/stateManagementStreamableHttp.test.ts
+++ b/src/integration-tests/stateManagementStreamableHttp.test.ts
@@ -5,7 +5,7 @@ import { Client } from '../client/index.js';
 import { StreamableHTTPClientTransport } from '../client/streamableHttp.js';
 import { McpServer } from '../server/mcp.js';
 import { StreamableHTTPServerTransport } from '../server/streamableHttp.js';
-import { CallToolResultSchema, ListToolsResultSchema, ListResourcesResultSchema, ListPromptsResultSchema } from '../types.js';
+import { CallToolResultSchema, ListToolsResultSchema, ListResourcesResultSchema, ListPromptsResultSchema, DEFAULT_NEGOTIATED_PROTOCOL_VERSION } from '../types.js';
 import { z } from 'zod';
 
 describe('Streamable HTTP Transport Session Management', () => {
@@ -211,6 +211,27 @@ describe('Streamable HTTP Transport Session Management', () => {
       // Clean up
       await transport.close();
     });
+
+    it('should set protocol version after connecting', async () => {
+      // Create and connect a client
+      const client = new Client({
+        name: 'test-client',
+        version: '1.0.0'
+      });
+
+      const transport = new StreamableHTTPClientTransport(baseUrl);
+      
+      // Verify protocol version is not set before connecting
+      expect(transport.protocolVersion).toBeUndefined();
+      
+      await client.connect(transport);
+      
+      // Verify protocol version is set after connecting
+      expect(transport.protocolVersion).toBe(DEFAULT_NEGOTIATED_PROTOCOL_VERSION);
+      
+      // Clean up
+      await transport.close();
+    });
   });
 
   describe('Stateful Mode', () => {
diff --git a/src/server/completable.ts b/src/server/completable.ts
index 3b5bc164..652eaf72 100644
--- a/src/server/completable.ts
+++ b/src/server/completable.ts
@@ -15,6 +15,9 @@ export enum McpZodTypeKind {
 
 export type CompleteCallback<T extends ZodTypeAny = ZodTypeAny> = (
   value: T["_input"],
+  context?: {
+    arguments?: Record<string, string>;
+  },
 ) => T["_input"][] | Promise<T["_input"][]>;
 
 export interface CompletableDef<T extends ZodTypeAny = ZodTypeAny>
diff --git a/src/server/index.ts b/src/server/index.ts
index 5d482d32..10ae2fad 100644
--- a/src/server/index.ts
+++ b/src/server/index.ts
@@ -265,10 +265,12 @@ export class Server<
     this._clientCapabilities = request.params.capabilities;
     this._clientVersion = request.params.clientInfo;
 
-    return {
-      protocolVersion: SUPPORTED_PROTOCOL_VERSIONS.includes(requestedVersion)
+    const protocolVersion = SUPPORTED_PROTOCOL_VERSIONS.includes(requestedVersion)
         ? requestedVersion
-        : LATEST_PROTOCOL_VERSION,
+        : LATEST_PROTOCOL_VERSION;
+
+    return {
+      protocolVersion,
       capabilities: this.getCapabilities(),
       serverInfo: this._serverInfo,
       ...(this._instructions && { instructions: this._instructions }),
diff --git a/src/server/mcp.test.ts b/src/server/mcp.test.ts
index 7cb0c489..7fb6bd55 100644
--- a/src/server/mcp.test.ts
+++ b/src/server/mcp.test.ts
@@ -19,6 +19,7 @@ import {
 import { ResourceTemplate } from "./mcp.js";
 import { completable } from "./completable.js";
 import { UriTemplate } from "../shared/uriTemplate.js";
+import { getDisplayName } from "../shared/metadataUtils.js";
 
 describe("McpServer", () => {
   /***
@@ -3458,6 +3459,555 @@ describe("prompt()", () => {
     expect(typeof receivedRequestId === 'string' || typeof receivedRequestId === 'number').toBe(true);
     expect(result.messages[0].content.text).toContain("Received request ID:");
   });
+
+  /***
+   * Test: Resource Template Metadata Priority
+   */
+  test("should prioritize individual resource metadata over template metadata", async () => {
+    const mcpServer = new McpServer({
+      name: "test server",
+      version: "1.0",
+    });
+    const client = new Client({
+      name: "test client",
+      version: "1.0",
+    });
+
+    mcpServer.resource(
+      "test",
+      new ResourceTemplate("test://resource/{id}", {
+        list: async () => ({
+          resources: [
+            {
+              name: "Resource 1",
+              uri: "test://resource/1",
+              description: "Individual resource description",
+              mimeType: "text/plain",
+            },
+            {
+              name: "Resource 2",
+              uri: "test://resource/2",
+              // This resource has no description or mimeType
+            },
+          ],
+        }),
+      }),
+      {
+        description: "Template description",
+        mimeType: "application/json",
+      },
+      async (uri) => ({
+        contents: [
+          {
+            uri: uri.href,
+            text: "Test content",
+          },
+        ],
+      }),
+    );
+
+    const [clientTransport, serverTransport] =
+      InMemoryTransport.createLinkedPair();
+
+    await Promise.all([
+      client.connect(clientTransport),
+      mcpServer.server.connect(serverTransport),
+    ]);
+
+    const result = await client.request(
+      {
+        method: "resources/list",
+      },
+      ListResourcesResultSchema,
+    );
+
+    expect(result.resources).toHaveLength(2);
+
+    // Resource 1 should have its own metadata
+    expect(result.resources[0].name).toBe("Resource 1");
+    expect(result.resources[0].description).toBe("Individual resource description");
+    expect(result.resources[0].mimeType).toBe("text/plain");
+
+    // Resource 2 should inherit template metadata
+    expect(result.resources[1].name).toBe("Resource 2");
+    expect(result.resources[1].description).toBe("Template description");
+    expect(result.resources[1].mimeType).toBe("application/json");
+  });
+
+  /***
+   * Test: Resource Template Metadata Overrides All Fields
+   */
+  test("should allow resource to override all template metadata fields", async () => {
+    const mcpServer = new McpServer({
+      name: "test server",
+      version: "1.0",
+    });
+    const client = new Client({
+      name: "test client",
+      version: "1.0",
+    });
+
+    mcpServer.resource(
+      "test",
+      new ResourceTemplate("test://resource/{id}", {
+        list: async () => ({
+          resources: [
+            {
+              name: "Overridden Name",
+              uri: "test://resource/1",
+              description: "Overridden description",
+              mimeType: "text/markdown",
+              // Add any other metadata fields if they exist
+            },
+          ],
+        }),
+      }),
+      {
+        name: "Template Name",
+        description: "Template description",
+        mimeType: "application/json",
+      },
+      async (uri) => ({
+        contents: [
+          {
+            uri: uri.href,
+            text: "Test content",
+          },
+        ],
+      }),
+    );
+
+    const [clientTransport, serverTransport] =
+      InMemoryTransport.createLinkedPair();
+
+    await Promise.all([
+      client.connect(clientTransport),
+      mcpServer.server.connect(serverTransport),
+    ]);
+
+    const result = await client.request(
+      {
+        method: "resources/list",
+      },
+      ListResourcesResultSchema,
+    );
+
+    expect(result.resources).toHaveLength(1);
+
+    // All fields should be from the individual resource, not the template
+    expect(result.resources[0].name).toBe("Overridden Name");
+    expect(result.resources[0].description).toBe("Overridden description");
+    expect(result.resources[0].mimeType).toBe("text/markdown");
+  });
+});
+
+describe("Tool title precedence", () => {
+  test("should follow correct title precedence: title → annotations.title → name", async () => {
+    const mcpServer = new McpServer({
+      name: "test server",
+      version: "1.0",
+    });
+    const client = new Client({
+      name: "test client",
+      version: "1.0",
+    });
+
+    // Tool 1: Only name
+    mcpServer.tool(
+      "tool_name_only",
+      async () => ({
+        content: [{ type: "text", text: "Response" }],
+      })
+    );
+
+    // Tool 2: Name and annotations.title
+    mcpServer.tool(
+      "tool_with_annotations_title",
+      "Tool with annotations title",
+      {
+        title: "Annotations Title"
+      },
+      async () => ({
+        content: [{ type: "text", text: "Response" }],
+      })
+    );
+
+    // Tool 3: Name and title (using registerTool)
+    mcpServer.registerTool(
+      "tool_with_title",
+      {
+        title: "Regular Title",
+        description: "Tool with regular title"
+      },
+      async () => ({
+        content: [{ type: "text", text: "Response" }],
+      })
+    );
+
+    // Tool 4: All three - title should win
+    mcpServer.registerTool(
+      "tool_with_all_titles",
+      {
+        title: "Regular Title Wins",
+        description: "Tool with all titles",
+        annotations: {
+          title: "Annotations Title Should Not Show"
+        }
+      },
+      async () => ({
+        content: [{ type: "text", text: "Response" }],
+      })
+    );
+
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+    await Promise.all([
+      client.connect(clientTransport),
+      mcpServer.connect(serverTransport),
+    ]);
+
+    const result = await client.request(
+      { method: "tools/list" },
+      ListToolsResultSchema,
+    );
+
+
+    expect(result.tools).toHaveLength(4);
+
+    // Tool 1: Only name - should display name
+    const tool1 = result.tools.find(t => t.name === "tool_name_only");
+    expect(tool1).toBeDefined();
+    expect(getDisplayName(tool1!)).toBe("tool_name_only");
+
+    // Tool 2: Name and annotations.title - should display annotations.title
+    const tool2 = result.tools.find(t => t.name === "tool_with_annotations_title");
+    expect(tool2).toBeDefined();
+    expect(tool2!.annotations?.title).toBe("Annotations Title");
+    expect(getDisplayName(tool2!)).toBe("Annotations Title");
+
+    // Tool 3: Name and title - should display title
+    const tool3 = result.tools.find(t => t.name === "tool_with_title");
+    expect(tool3).toBeDefined();
+    expect(tool3!.title).toBe("Regular Title");
+    expect(getDisplayName(tool3!)).toBe("Regular Title");
+
+    // Tool 4: All three - title should take precedence
+    const tool4 = result.tools.find(t => t.name === "tool_with_all_titles");
+    expect(tool4).toBeDefined();
+    expect(tool4!.title).toBe("Regular Title Wins");
+    expect(tool4!.annotations?.title).toBe("Annotations Title Should Not Show");
+    expect(getDisplayName(tool4!)).toBe("Regular Title Wins");
+  });
+
+  test("getDisplayName unit tests for title precedence", () => {
+
+    // Test 1: Only name
+    expect(getDisplayName({ name: "tool_name" })).toBe("tool_name");
+
+    // Test 2: Name and title - title wins
+    expect(getDisplayName({
+      name: "tool_name",
+      title: "Tool Title"
+    })).toBe("Tool Title");
+
+    // Test 3: Name and annotations.title - annotations.title wins
+    expect(getDisplayName({
+      name: "tool_name",
+      annotations: { title: "Annotations Title" }
+    })).toBe("Annotations Title");
+
+    // Test 4: All three - title wins (correct precedence)
+    expect(getDisplayName({
+      name: "tool_name",
+      title: "Regular Title",
+      annotations: { title: "Annotations Title" }
+    })).toBe("Regular Title");
+
+    // Test 5: Empty title should not be used
+    expect(getDisplayName({
+      name: "tool_name",
+      title: "",
+      annotations: { title: "Annotations Title" }
+    })).toBe("Annotations Title");
+
+    // Test 6: Undefined vs null handling
+    expect(getDisplayName({
+      name: "tool_name",
+      title: undefined,
+      annotations: { title: "Annotations Title" }
+    })).toBe("Annotations Title");
+  });
+
+  test("should support resource template completion with resolved context", async () => {
+    const mcpServer = new McpServer({
+      name: "test server",
+      version: "1.0",
+    });
+
+    const client = new Client({
+      name: "test client",
+      version: "1.0",
+    });
+
+    mcpServer.registerResource(
+      "test",
+      new ResourceTemplate("github://repos/{owner}/{repo}", {
+        list: undefined,
+        complete: {
+          repo: (value, context) => {
+            if (context?.arguments?.["owner"] === "org1") {
+              return ["project1", "project2", "project3"].filter(r => r.startsWith(value));
+            } else if (context?.arguments?.["owner"] === "org2") {
+              return ["repo1", "repo2", "repo3"].filter(r => r.startsWith(value));
+            }
+            return [];
+          },
+        },
+      }),
+      {
+        title: "GitHub Repository",
+        description: "Repository information"
+      },
+      async () => ({
+        contents: [
+          {
+            uri: "github://repos/test/test",
+            text: "Test content",
+          },
+        ],
+      }),
+    );
+
+    const [clientTransport, serverTransport] =
+      InMemoryTransport.createLinkedPair();
+
+    await Promise.all([
+      client.connect(clientTransport),
+      mcpServer.server.connect(serverTransport),
+    ]);
+
+    // Test with microsoft owner
+    const result1 = await client.request(
+      {
+        method: "completion/complete",
+        params: {
+          ref: {
+            type: "ref/resource",
+            uri: "github://repos/{owner}/{repo}",
+          },
+          argument: {
+            name: "repo",
+            value: "p",
+          },
+          context: {
+            arguments: {
+              owner: "org1",
+            },
+          },
+        },
+      },
+      CompleteResultSchema,
+    );
+
+    expect(result1.completion.values).toEqual(["project1", "project2", "project3"]);
+    expect(result1.completion.total).toBe(3);
+
+    // Test with facebook owner
+    const result2 = await client.request(
+      {
+        method: "completion/complete",
+        params: {
+          ref: {
+            type: "ref/resource",
+            uri: "github://repos/{owner}/{repo}",
+          },
+          argument: {
+            name: "repo",
+            value: "r",
+          },
+          context: {
+            arguments: {
+              owner: "org2",
+            },
+          },
+        },
+      },
+      CompleteResultSchema,
+    );
+
+    expect(result2.completion.values).toEqual(["repo1", "repo2", "repo3"]);
+    expect(result2.completion.total).toBe(3);
+
+    // Test with no resolved context
+    const result3 = await client.request(
+      {
+        method: "completion/complete",
+        params: {
+          ref: {
+            type: "ref/resource",
+            uri: "github://repos/{owner}/{repo}",
+          },
+          argument: {
+            name: "repo",
+            value: "t",
+          },
+        },
+      },
+      CompleteResultSchema,
+    );
+
+    expect(result3.completion.values).toEqual([]);
+    expect(result3.completion.total).toBe(0);
+  });
+
+  test("should support prompt argument completion with resolved context", async () => {
+    const mcpServer = new McpServer({
+      name: "test server",
+      version: "1.0",
+    });
+
+    const client = new Client({
+      name: "test client",
+      version: "1.0",
+    });
+
+    mcpServer.registerPrompt(
+      "test-prompt",
+      {
+        title: "Team Greeting",
+        description: "Generate a greeting for team members",
+        argsSchema: {
+          department: completable(z.string(), (value) => {
+            return ["engineering", "sales", "marketing", "support"].filter(d => d.startsWith(value));
+          }),
+          name: completable(z.string(), (value, context) => {
+            const department = context?.arguments?.["department"];
+            if (department === "engineering") {
+              return ["Alice", "Bob", "Charlie"].filter(n => n.startsWith(value));
+            } else if (department === "sales") {
+              return ["David", "Eve", "Frank"].filter(n => n.startsWith(value));
+            } else if (department === "marketing") {
+              return ["Grace", "Henry", "Iris"].filter(n => n.startsWith(value));
+            }
+            return ["Guest"].filter(n => n.startsWith(value));
+          }),
+        }
+      },
+      async ({ department, name }) => ({
+        messages: [
+          {
+            role: "assistant",
+            content: {
+              type: "text",
+              text: `Hello ${name}, welcome to the ${department} team!`,
+            },
+          },
+        ],
+      }),
+    );
+
+    const [clientTransport, serverTransport] =
+      InMemoryTransport.createLinkedPair();
+
+    await Promise.all([
+      client.connect(clientTransport),
+      mcpServer.server.connect(serverTransport),
+    ]);
+
+    // Test with engineering department
+    const result1 = await client.request(
+      {
+        method: "completion/complete",
+        params: {
+          ref: {
+            type: "ref/prompt",
+            name: "test-prompt",
+          },
+          argument: {
+            name: "name",
+            value: "A",
+          },
+          context: {
+            arguments: {
+              department: "engineering",
+            },
+          },
+        },
+      },
+      CompleteResultSchema,
+    );
+
+    expect(result1.completion.values).toEqual(["Alice"]);
+
+    // Test with sales department
+    const result2 = await client.request(
+      {
+        method: "completion/complete",
+        params: {
+          ref: {
+            type: "ref/prompt",
+            name: "test-prompt",
+          },
+          argument: {
+            name: "name",
+            value: "D",
+          },
+          context: {
+            arguments: {
+              department: "sales",
+            },
+          },
+        },
+      },
+      CompleteResultSchema,
+    );
+
+    expect(result2.completion.values).toEqual(["David"]);
+
+    // Test with marketing department
+    const result3 = await client.request(
+      {
+        method: "completion/complete",
+        params: {
+          ref: {
+            type: "ref/prompt",
+            name: "test-prompt",
+          },
+          argument: {
+            name: "name",
+            value: "G",
+          },
+          context: {
+            arguments: {
+              department: "marketing",
+            },
+          },
+        },
+      },
+      CompleteResultSchema,
+    );
+
+    expect(result3.completion.values).toEqual(["Grace"]);
+
+    // Test with no resolved context
+    const result4 = await client.request(
+      {
+        method: "completion/complete",
+        params: {
+          ref: {
+            type: "ref/prompt",
+            name: "test-prompt",
+          },
+          argument: {
+            name: "name",
+            value: "G",
+          },
+        },
+      },
+      CompleteResultSchema,
+    );
+
+    expect(result4.completion.values).toEqual(["Guest"]);
+  });
 });
 
 describe("elicitInput()", () => {
diff --git a/src/server/mcp.ts b/src/server/mcp.ts
index 38c869c7..3d9673da 100644
--- a/src/server/mcp.ts
+++ b/src/server/mcp.ts
@@ -21,7 +21,8 @@ import {
   CompleteRequest,
   CompleteResult,
   PromptReference,
-  ResourceReference,
+  ResourceTemplateReference,
+  BaseMetadata,
   Resource,
   ListResourcesResult,
   ListResourceTemplatesRequestSchema,
@@ -113,6 +114,7 @@ export class McpServer {
           ([name, tool]): Tool => {
             const toolDefinition: Tool = {
               name,
+              title: tool.title,
               description: tool.description,
               inputSchema: tool.inputSchema
                 ? (zodToJsonSchema(tool.inputSchema, {
@@ -124,7 +126,7 @@ export class McpServer {
 
             if (tool.outputSchema) {
               toolDefinition.outputSchema = zodToJsonSchema(
-                tool.outputSchema, 
+                tool.outputSchema,
                 { strictUnions: true }
               ) as Tool["outputSchema"];
             }
@@ -291,13 +293,13 @@ export class McpServer {
     }
 
     const def: CompletableDef<ZodString> = field._def;
-    const suggestions = await def.complete(request.params.argument.value);
+    const suggestions = await def.complete(request.params.argument.value, request.params.context);
     return createCompletionResult(suggestions);
   }
 
   private async handleResourceCompletion(
     request: CompleteRequest,
-    ref: ResourceReference,
+    ref: ResourceTemplateReference,
   ): Promise<CompleteResult> {
     const template = Object.values(this._registeredResourceTemplates).find(
       (t) => t.resourceTemplate.uriTemplate.toString() === ref.uri,
@@ -322,7 +324,7 @@ export class McpServer {
       return EMPTY_COMPLETION_RESULT;
     }
 
-    const suggestions = await completer(request.params.argument.value);
+    const suggestions = await completer(request.params.argument.value, request.params.context);
     return createCompletionResult(suggestions);
   }
 
@@ -373,8 +375,9 @@ export class McpServer {
           const result = await template.resourceTemplate.listCallback(extra);
           for (const resource of result.resources) {
             templateResources.push({
-              ...resource,
               ...template.metadata,
+              // the defined resource metadata should override the template metadata if present
+              ...resource,
             });
           }
         }
@@ -468,6 +471,7 @@ export class McpServer {
           ([name, prompt]): Prompt => {
             return {
               name,
+              title: prompt.title,
               description: prompt.description,
               arguments: prompt.argsSchema
                 ? promptArgumentsFromSchema(prompt.argsSchema)
@@ -575,27 +579,13 @@ export class McpServer {
         throw new Error(`Resource ${uriOrTemplate} is already registered`);
       }
 
-      const registeredResource: RegisteredResource = {
+      const registeredResource = this._createRegisteredResource(
         name,
+        undefined,
+        uriOrTemplate,
         metadata,
-        readCallback: readCallback as ReadResourceCallback,
-        enabled: true,
-        disable: () => registeredResource.update({ enabled: false }),
-        enable: () => registeredResource.update({ enabled: true }),
-        remove: () => registeredResource.update({ uri: null }),
-        update: (updates) => {
-          if (typeof updates.uri !== "undefined" && updates.uri !== uriOrTemplate) {
-            delete this._registeredResources[uriOrTemplate]
-            if (updates.uri) this._registeredResources[updates.uri] = registeredResource
-          }
-          if (typeof updates.name !== "undefined") registeredResource.name = updates.name
-          if (typeof updates.metadata !== "undefined") registeredResource.metadata = updates.metadata
-          if (typeof updates.callback !== "undefined") registeredResource.readCallback = updates.callback
-          if (typeof updates.enabled !== "undefined") registeredResource.enabled = updates.enabled
-          this.sendResourceListChanged()
-        },
-      };
-      this._registeredResources[uriOrTemplate] = registeredResource;
+        readCallback as ReadResourceCallback
+      );
 
       this.setResourceRequestHandlers();
       this.sendResourceListChanged();
@@ -605,27 +595,13 @@ export class McpServer {
         throw new Error(`Resource template ${name} is already registered`);
       }
 
-      const registeredResourceTemplate: RegisteredResourceTemplate = {
-        resourceTemplate: uriOrTemplate,
+      const registeredResourceTemplate = this._createRegisteredResourceTemplate(
+        name,
+        undefined,
+        uriOrTemplate,
         metadata,
-        readCallback: readCallback as ReadResourceTemplateCallback,
-        enabled: true,
-        disable: () => registeredResourceTemplate.update({ enabled: false }),
-        enable: () => registeredResourceTemplate.update({ enabled: true }),
-        remove: () => registeredResourceTemplate.update({ name: null }),
-        update: (updates) => {
-          if (typeof updates.name !== "undefined" && updates.name !== name) {
-            delete this._registeredResourceTemplates[name]
-            if (updates.name) this._registeredResourceTemplates[updates.name] = registeredResourceTemplate
-          }
-          if (typeof updates.template !== "undefined") registeredResourceTemplate.resourceTemplate = updates.template
-          if (typeof updates.metadata !== "undefined") registeredResourceTemplate.metadata = updates.metadata
-          if (typeof updates.callback !== "undefined") registeredResourceTemplate.readCallback = updates.callback
-          if (typeof updates.enabled !== "undefined") registeredResourceTemplate.enabled = updates.enabled
-          this.sendResourceListChanged()
-        },
-      };
-      this._registeredResourceTemplates[name] = registeredResourceTemplate;
+        readCallback as ReadResourceTemplateCallback
+      );
 
       this.setResourceRequestHandlers();
       this.sendResourceListChanged();
@@ -633,8 +609,153 @@ export class McpServer {
     }
   }
 
+  /**
+   * Registers a resource with a config object and callback.
+   * For static resources, use a URI string. For dynamic resources, use a ResourceTemplate.
+   */
+  registerResource(
+    name: string,
+    uriOrTemplate: string | ResourceTemplate,
+    config: ResourceMetadata,
+    readCallback: ReadResourceCallback | ReadResourceTemplateCallback
+  ): RegisteredResource | RegisteredResourceTemplate {
+    if (typeof uriOrTemplate === "string") {
+      if (this._registeredResources[uriOrTemplate]) {
+        throw new Error(`Resource ${uriOrTemplate} is already registered`);
+      }
+
+      const registeredResource = this._createRegisteredResource(
+        name,
+        (config as BaseMetadata).title,
+        uriOrTemplate,
+        config,
+        readCallback as ReadResourceCallback
+      );
+
+      this.setResourceRequestHandlers();
+      this.sendResourceListChanged();
+      return registeredResource;
+    } else {
+      if (this._registeredResourceTemplates[name]) {
+        throw new Error(`Resource template ${name} is already registered`);
+      }
+
+      const registeredResourceTemplate = this._createRegisteredResourceTemplate(
+        name,
+        (config as BaseMetadata).title,
+        uriOrTemplate,
+        config,
+        readCallback as ReadResourceTemplateCallback
+      );
+
+      this.setResourceRequestHandlers();
+      this.sendResourceListChanged();
+      return registeredResourceTemplate;
+    }
+  }
+
+  private _createRegisteredResource(
+    name: string,
+    title: string | undefined,
+    uri: string,
+    metadata: ResourceMetadata | undefined,
+    readCallback: ReadResourceCallback
+  ): RegisteredResource {
+    const registeredResource: RegisteredResource = {
+      name,
+      title,
+      metadata,
+      readCallback,
+      enabled: true,
+      disable: () => registeredResource.update({ enabled: false }),
+      enable: () => registeredResource.update({ enabled: true }),
+      remove: () => registeredResource.update({ uri: null }),
+      update: (updates) => {
+        if (typeof updates.uri !== "undefined" && updates.uri !== uri) {
+          delete this._registeredResources[uri]
+          if (updates.uri) this._registeredResources[updates.uri] = registeredResource
+        }
+        if (typeof updates.name !== "undefined") registeredResource.name = updates.name
+        if (typeof updates.title !== "undefined") registeredResource.title = updates.title
+        if (typeof updates.metadata !== "undefined") registeredResource.metadata = updates.metadata
+        if (typeof updates.callback !== "undefined") registeredResource.readCallback = updates.callback
+        if (typeof updates.enabled !== "undefined") registeredResource.enabled = updates.enabled
+        this.sendResourceListChanged()
+      },
+    };
+    this._registeredResources[uri] = registeredResource;
+    return registeredResource;
+  }
+
+  private _createRegisteredResourceTemplate(
+    name: string,
+    title: string | undefined,
+    template: ResourceTemplate,
+    metadata: ResourceMetadata | undefined,
+    readCallback: ReadResourceTemplateCallback
+  ): RegisteredResourceTemplate {
+    const registeredResourceTemplate: RegisteredResourceTemplate = {
+      resourceTemplate: template,
+      title,
+      metadata,
+      readCallback,
+      enabled: true,
+      disable: () => registeredResourceTemplate.update({ enabled: false }),
+      enable: () => registeredResourceTemplate.update({ enabled: true }),
+      remove: () => registeredResourceTemplate.update({ name: null }),
+      update: (updates) => {
+        if (typeof updates.name !== "undefined" && updates.name !== name) {
+          delete this._registeredResourceTemplates[name]
+          if (updates.name) this._registeredResourceTemplates[updates.name] = registeredResourceTemplate
+        }
+        if (typeof updates.title !== "undefined") registeredResourceTemplate.title = updates.title
+        if (typeof updates.template !== "undefined") registeredResourceTemplate.resourceTemplate = updates.template
+        if (typeof updates.metadata !== "undefined") registeredResourceTemplate.metadata = updates.metadata
+        if (typeof updates.callback !== "undefined") registeredResourceTemplate.readCallback = updates.callback
+        if (typeof updates.enabled !== "undefined") registeredResourceTemplate.enabled = updates.enabled
+        this.sendResourceListChanged()
+      },
+    };
+    this._registeredResourceTemplates[name] = registeredResourceTemplate;
+    return registeredResourceTemplate;
+  }
+
+  private _createRegisteredPrompt(
+    name: string,
+    title: string | undefined,
+    description: string | undefined,
+    argsSchema: PromptArgsRawShape | undefined,
+    callback: PromptCallback<PromptArgsRawShape | undefined>
+  ): RegisteredPrompt {
+    const registeredPrompt: RegisteredPrompt = {
+      title,
+      description,
+      argsSchema: argsSchema === undefined ? undefined : z.object(argsSchema),
+      callback,
+      enabled: true,
+      disable: () => registeredPrompt.update({ enabled: false }),
+      enable: () => registeredPrompt.update({ enabled: true }),
+      remove: () => registeredPrompt.update({ name: null }),
+      update: (updates) => {
+        if (typeof updates.name !== "undefined" && updates.name !== name) {
+          delete this._registeredPrompts[name]
+          if (updates.name) this._registeredPrompts[updates.name] = registeredPrompt
+        }
+        if (typeof updates.title !== "undefined") registeredPrompt.title = updates.title
+        if (typeof updates.description !== "undefined") registeredPrompt.description = updates.description
+        if (typeof updates.argsSchema !== "undefined") registeredPrompt.argsSchema = z.object(updates.argsSchema)
+        if (typeof updates.callback !== "undefined") registeredPrompt.callback = updates.callback
+        if (typeof updates.enabled !== "undefined") registeredPrompt.enabled = updates.enabled
+        this.sendPromptListChanged()
+      },
+    };
+    this._registeredPrompts[name] = registeredPrompt;
+    return registeredPrompt;
+  }
+
   private _createRegisteredTool(
     name: string,
+    title: string | undefined,
     description: string | undefined,
     inputSchema: ZodRawShape | undefined,
     outputSchema: ZodRawShape | undefined,
@@ -642,6 +763,7 @@ export class McpServer {
     callback: ToolCallback<ZodRawShape | undefined>
   ): RegisteredTool {
     const registeredTool: RegisteredTool = {
+      title,
       description,
       inputSchema:
         inputSchema === undefined ? undefined : z.object(inputSchema),
@@ -658,6 +780,7 @@ export class McpServer {
           delete this._registeredTools[name]
           if (updates.name) this._registeredTools[updates.name] = registeredTool
         }
+        if (typeof updates.title !== "undefined") registeredTool.title = updates.title
         if (typeof updates.description !== "undefined") registeredTool.description = updates.description
         if (typeof updates.paramsSchema !== "undefined") registeredTool.inputSchema = z.object(updates.paramsSchema)
         if (typeof updates.callback !== "undefined") registeredTool.callback = updates.callback
@@ -779,7 +902,7 @@ export class McpServer {
     }
     const callback = rest[0] as ToolCallback<ZodRawShape | undefined>;
 
-    return this._createRegisteredTool(name, description, inputSchema, outputSchema, annotations, callback)
+    return this._createRegisteredTool(name, undefined, description, inputSchema, outputSchema, annotations, callback)
   }
 
   /**
@@ -788,6 +911,7 @@ export class McpServer {
   registerTool<InputArgs extends ZodRawShape, OutputArgs extends ZodRawShape>(
     name: string,
     config: {
+      title?: string;
       description?: string;
       inputSchema?: InputArgs;
       outputSchema?: OutputArgs;
@@ -799,16 +923,17 @@ export class McpServer {
       throw new Error(`Tool ${name} is already registered`);
     }
 
-    const { description, inputSchema, outputSchema, annotations } = config;
+    const { title, description, inputSchema, outputSchema, annotations } = config;
 
     return this._createRegisteredTool(
       name,
+      title,
       description,
       inputSchema,
       outputSchema,
       annotations,
       cb as ToolCallback<ZodRawShape | undefined>
-    )
+    );
   }
 
   /**
@@ -856,27 +981,13 @@ export class McpServer {
     }
 
     const cb = rest[0] as PromptCallback<PromptArgsRawShape | undefined>;
-    const registeredPrompt: RegisteredPrompt = {
+    const registeredPrompt = this._createRegisteredPrompt(
+      name,
+      undefined,
       description,
-      argsSchema: argsSchema === undefined ? undefined : z.object(argsSchema),
-      callback: cb,
-      enabled: true,
-      disable: () => registeredPrompt.update({ enabled: false }),
-      enable: () => registeredPrompt.update({ enabled: true }),
-      remove: () => registeredPrompt.update({ name: null }),
-      update: (updates) => {
-        if (typeof updates.name !== "undefined" && updates.name !== name) {
-          delete this._registeredPrompts[name]
-          if (updates.name) this._registeredPrompts[updates.name] = registeredPrompt
-        }
-        if (typeof updates.description !== "undefined") registeredPrompt.description = updates.description
-        if (typeof updates.argsSchema !== "undefined") registeredPrompt.argsSchema = z.object(updates.argsSchema)
-        if (typeof updates.callback !== "undefined") registeredPrompt.callback = updates.callback
-        if (typeof updates.enabled !== "undefined") registeredPrompt.enabled = updates.enabled
-        this.sendPromptListChanged()
-      },
-    };
-    this._registeredPrompts[name] = registeredPrompt;
+      argsSchema,
+      cb
+    );
 
     this.setPromptRequestHandlers();
     this.sendPromptListChanged()
@@ -884,6 +995,38 @@ export class McpServer {
     return registeredPrompt
   }
 
+  /**
+   * Registers a prompt with a config object and callback.
+   */
+  registerPrompt<Args extends PromptArgsRawShape>(
+    name: string,
+    config: {
+      title?: string;
+      description?: string;
+      argsSchema?: Args;
+    },
+    cb: PromptCallback<Args>
+  ): RegisteredPrompt {
+    if (this._registeredPrompts[name]) {
+      throw new Error(`Prompt ${name} is already registered`);
+    }
+
+    const { title, description, argsSchema } = config;
+
+    const registeredPrompt = this._createRegisteredPrompt(
+      name,
+      title,
+      description,
+      argsSchema,
+      cb as PromptCallback<PromptArgsRawShape | undefined>
+    );
+
+    this.setPromptRequestHandlers();
+    this.sendPromptListChanged()
+
+    return registeredPrompt;
+  }
+
   /**
    * Checks if the server is connected to a transport.
    * @returns True if the server is connected
@@ -925,6 +1068,9 @@ export class McpServer {
  */
 export type CompleteResourceTemplateCallback = (
   value: string,
+  context?: {
+    arguments?: Record<string, string>;
+  },
 ) => string[] | Promise<string[]>;
 
 /**
@@ -999,6 +1145,7 @@ export type ToolCallback<Args extends undefined | ZodRawShape = undefined> =
   : (extra: RequestHandlerExtra<ServerRequest, ServerNotification>) => CallToolResult | Promise<CallToolResult>;
 
 export type RegisteredTool = {
+  title?: string;
   description?: string;
   inputSchema?: AnyZodObject;
   outputSchema?: AnyZodObject;
@@ -1008,15 +1155,16 @@ export type RegisteredTool = {
   enable(): void;
   disable(): void;
   update<InputArgs extends ZodRawShape, OutputArgs extends ZodRawShape>(
-    updates: { 
-      name?: string | null, 
-      description?: string, 
-      paramsSchema?: InputArgs, 
-      outputSchema?: OutputArgs, 
-      annotations?: ToolAnnotations, 
-      callback?: ToolCallback<InputArgs>, 
-      enabled?: boolean 
-  }): void
+    updates: {
+      name?: string | null,
+      title?: string,
+      description?: string,
+      paramsSchema?: InputArgs,
+      outputSchema?: OutputArgs,
+      annotations?: ToolAnnotations,
+      callback?: ToolCallback<InputArgs>,
+      enabled?: boolean
+    }): void
   remove(): void
 };
 
@@ -1064,12 +1212,13 @@ export type ReadResourceCallback = (
 
 export type RegisteredResource = {
   name: string;
+  title?: string;
   metadata?: ResourceMetadata;
   readCallback: ReadResourceCallback;
   enabled: boolean;
   enable(): void;
   disable(): void;
-  update(updates: { name?: string, uri?: string | null, metadata?: ResourceMetadata, callback?: ReadResourceCallback, enabled?: boolean }): void
+  update(updates: { name?: string, title?: string, uri?: string | null, metadata?: ResourceMetadata, callback?: ReadResourceCallback, enabled?: boolean }): void
   remove(): void
 };
 
@@ -1084,12 +1233,13 @@ export type ReadResourceTemplateCallback = (
 
 export type RegisteredResourceTemplate = {
   resourceTemplate: ResourceTemplate;
+  title?: string;
   metadata?: ResourceMetadata;
   readCallback: ReadResourceTemplateCallback;
   enabled: boolean;
   enable(): void;
   disable(): void;
-  update(updates: { name?: string | null, template?: ResourceTemplate, metadata?: ResourceMetadata, callback?: ReadResourceTemplateCallback, enabled?: boolean }): void
+  update(updates: { name?: string | null, title?: string, template?: ResourceTemplate, metadata?: ResourceMetadata, callback?: ReadResourceTemplateCallback, enabled?: boolean }): void
   remove(): void
 };
 
@@ -1109,13 +1259,14 @@ export type PromptCallback<
   : (extra: RequestHandlerExtra<ServerRequest, ServerNotification>) => GetPromptResult | Promise<GetPromptResult>;
 
 export type RegisteredPrompt = {
+  title?: string;
   description?: string;
   argsSchema?: ZodObject<PromptArgsRawShape>;
   callback: PromptCallback<undefined | PromptArgsRawShape>;
   enabled: boolean;
   enable(): void;
   disable(): void;
-  update<Args extends PromptArgsRawShape>(updates: { name?: string | null, description?: string, argsSchema?: Args, callback?: PromptCallback<Args>, enabled?: boolean }): void
+  update<Args extends PromptArgsRawShape>(updates: { name?: string | null, title?: string, description?: string, argsSchema?: Args, callback?: PromptCallback<Args>, enabled?: boolean }): void
   remove(): void
 };
 
diff --git a/src/server/sse.ts b/src/server/sse.ts
index 03f6fefc..e9a4d53a 100644
--- a/src/server/sse.ts
+++ b/src/server/sse.ts
@@ -17,7 +17,6 @@ const MAXIMUM_MESSAGE_SIZE = "4mb";
 export class SSEServerTransport implements Transport {
   private _sseResponse?: ServerResponse;
   private _sessionId: string;
-
   onclose?: () => void;
   onerror?: (error: Error) => void;
   onmessage?: (message: JSONRPCMessage, extra?: { authInfo?: AuthInfo }) => void;
diff --git a/src/server/streamableHttp.test.ts b/src/server/streamableHttp.test.ts
index b961f6c4..d66083fe 100644
--- a/src/server/streamableHttp.test.ts
+++ b/src/server/streamableHttp.test.ts
@@ -185,6 +185,8 @@ async function sendPostRequest(baseUrl: URL, message: JSONRPCMessage | JSONRPCMe
 
   if (sessionId) {
     headers["mcp-session-id"] = sessionId;
+    // After initialization, include the protocol version header
+    headers["mcp-protocol-version"] = "2025-03-26";
   }
 
   return fetch(baseUrl, {
@@ -277,7 +279,7 @@ describe("StreamableHTTPServerTransport", () => {
     expectErrorResponse(errorData, -32600, /Only one initialization request is allowed/);
   });
 
-  it("should pandle post requests via sse response correctly", async () => {
+  it("should handle post requests via sse response correctly", async () => {
     sessionId = await initializeServer();
 
     const response = await sendPostRequest(baseUrl, TEST_MESSAGES.toolsList, sessionId);
@@ -376,6 +378,7 @@ describe("StreamableHTTPServerTransport", () => {
       headers: {
         Accept: "text/event-stream",
         "mcp-session-id": sessionId,
+        "mcp-protocol-version": "2025-03-26",
       },
     });
 
@@ -417,6 +420,7 @@ describe("StreamableHTTPServerTransport", () => {
       headers: {
         Accept: "text/event-stream",
         "mcp-session-id": sessionId,
+        "mcp-protocol-version": "2025-03-26",
       },
     });
 
@@ -448,6 +452,7 @@ describe("StreamableHTTPServerTransport", () => {
       headers: {
         Accept: "text/event-stream",
         "mcp-session-id": sessionId,
+        "mcp-protocol-version": "2025-03-26",
       },
     });
 
@@ -459,6 +464,7 @@ describe("StreamableHTTPServerTransport", () => {
       headers: {
         Accept: "text/event-stream",
         "mcp-session-id": sessionId,
+        "mcp-protocol-version": "2025-03-26",
       },
     });
 
@@ -477,6 +483,7 @@ describe("StreamableHTTPServerTransport", () => {
       headers: {
         Accept: "application/json",
         "mcp-session-id": sessionId,
+        "mcp-protocol-version": "2025-03-26",
       },
     });
 
@@ -670,6 +677,7 @@ describe("StreamableHTTPServerTransport", () => {
       headers: {
         Accept: "text/event-stream",
         "mcp-session-id": sessionId,
+        "mcp-protocol-version": "2025-03-26",
       },
     });
 
@@ -705,7 +713,10 @@ describe("StreamableHTTPServerTransport", () => {
     // Now DELETE the session
     const deleteResponse = await fetch(tempUrl, {
       method: "DELETE",
-      headers: { "mcp-session-id": tempSessionId || "" },
+      headers: {
+        "mcp-session-id": tempSessionId || "",
+        "mcp-protocol-version": "2025-03-26",
+      },
     });
 
     expect(deleteResponse.status).toBe(200);
@@ -721,13 +732,124 @@ describe("StreamableHTTPServerTransport", () => {
     // Try to delete with invalid session ID
     const response = await fetch(baseUrl, {
       method: "DELETE",
-      headers: { "mcp-session-id": "invalid-session-id" },
+      headers: {
+        "mcp-session-id": "invalid-session-id",
+        "mcp-protocol-version": "2025-03-26",
+      },
     });
 
     expect(response.status).toBe(404);
     const errorData = await response.json();
     expectErrorResponse(errorData, -32001, /Session not found/);
   });
+
+  describe("protocol version header validation", () => {
+    it("should accept requests with matching protocol version", async () => {
+      sessionId = await initializeServer();
+
+      // Send request with matching protocol version
+      const response = await sendPostRequest(baseUrl, TEST_MESSAGES.toolsList, sessionId);
+      
+      expect(response.status).toBe(200);
+    });
+
+    it("should accept requests without protocol version header", async () => {
+      sessionId = await initializeServer();
+
+      // Send request without protocol version header
+      const response = await fetch(baseUrl, {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/json",
+          Accept: "application/json, text/event-stream",
+          "mcp-session-id": sessionId,
+          // No mcp-protocol-version header
+        },
+        body: JSON.stringify(TEST_MESSAGES.toolsList),
+      });
+      
+      expect(response.status).toBe(200);
+    });
+
+    it("should reject requests with unsupported protocol version", async () => {
+      sessionId = await initializeServer();
+
+      // Send request with unsupported protocol version
+      const response = await fetch(baseUrl, {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/json",
+          Accept: "application/json, text/event-stream",
+          "mcp-session-id": sessionId,
+          "mcp-protocol-version": "1999-01-01", // Unsupported version
+        },
+        body: JSON.stringify(TEST_MESSAGES.toolsList),
+      });
+      
+      expect(response.status).toBe(400);
+      const errorData = await response.json();
+      expectErrorResponse(errorData, -32000, /Bad Request: Unsupported protocol version \(supported versions: .+\)/);
+    });
+
+    it("should accept when protocol version differs from negotiated version", async () => {
+      sessionId = await initializeServer();
+      
+      // Spy on console.warn to verify warning is logged
+      const warnSpy = jest.spyOn(console, 'warn').mockImplementation();
+
+      // Send request with different but supported protocol version
+      const response = await fetch(baseUrl, {
+        method: "POST", 
+        headers: {
+          "Content-Type": "application/json",
+          Accept: "application/json, text/event-stream",
+          "mcp-session-id": sessionId,
+          "mcp-protocol-version": "2024-11-05", // Different but supported version
+        },
+        body: JSON.stringify(TEST_MESSAGES.toolsList),
+      });
+      
+      // Request should still succeed
+      expect(response.status).toBe(200);
+      
+      warnSpy.mockRestore();
+    });
+
+    it("should handle protocol version validation for GET requests", async () => {
+      sessionId = await initializeServer();
+
+      // GET request with unsupported protocol version
+      const response = await fetch(baseUrl, {
+        method: "GET",
+        headers: {
+          Accept: "text/event-stream",
+          "mcp-session-id": sessionId,
+          "mcp-protocol-version": "invalid-version",
+        },
+      });
+      
+      expect(response.status).toBe(400);
+      const errorData = await response.json();
+      expectErrorResponse(errorData, -32000, /Bad Request: Unsupported protocol version \(supported versions: .+\)/);
+    });
+
+    it("should handle protocol version validation for DELETE requests", async () => {
+      sessionId = await initializeServer();
+
+      // DELETE request with unsupported protocol version
+      const response = await fetch(baseUrl, {
+        method: "DELETE",
+        headers: {
+          "mcp-session-id": sessionId,
+          "mcp-protocol-version": "invalid-version",
+        },
+      });
+      
+      expect(response.status).toBe(400);
+      const errorData = await response.json();
+      expectErrorResponse(errorData, -32000, /Bad Request: Unsupported protocol version \(supported versions: .+\)/);
+    });
+  });
 });
 
 describe("StreamableHTTPServerTransport with AuthInfo", () => {
@@ -1120,6 +1242,7 @@ describe("StreamableHTTPServerTransport with resumability", () => {
       headers: {
         Accept: "text/event-stream",
         "mcp-session-id": sessionId,
+        "mcp-protocol-version": "2025-03-26",
       },
     });
 
@@ -1196,6 +1319,7 @@ describe("StreamableHTTPServerTransport with resumability", () => {
       headers: {
         Accept: "text/event-stream",
         "mcp-session-id": sessionId,
+        "mcp-protocol-version": "2025-03-26",
         "last-event-id": firstEventId
       },
     });
@@ -1282,14 +1406,20 @@ describe("StreamableHTTPServerTransport in stateless mode", () => {
     // Open first SSE stream
     const stream1 = await fetch(baseUrl, {
       method: "GET",
-      headers: { Accept: "text/event-stream" },
+      headers: { 
+        Accept: "text/event-stream",
+        "mcp-protocol-version": "2025-03-26"
+      },
     });
     expect(stream1.status).toBe(200);
 
     // Open second SSE stream - should still be rejected, stateless mode still only allows one
     const stream2 = await fetch(baseUrl, {
       method: "GET",
-      headers: { Accept: "text/event-stream" },
+      headers: { 
+        Accept: "text/event-stream",
+        "mcp-protocol-version": "2025-03-26"
+      },
     });
     expect(stream2.status).toBe(409); // Conflict - only one stream allowed
   });
diff --git a/src/server/streamableHttp.ts b/src/server/streamableHttp.ts
index dc99c306..34b2ab68 100644
--- a/src/server/streamableHttp.ts
+++ b/src/server/streamableHttp.ts
@@ -1,6 +1,6 @@
 import { IncomingMessage, ServerResponse } from "node:http";
 import { Transport } from "../shared/transport.js";
-import { isInitializeRequest, isJSONRPCError, isJSONRPCRequest, isJSONRPCResponse, JSONRPCMessage, JSONRPCMessageSchema, RequestId } from "../types.js";
+import { isInitializeRequest, isJSONRPCError, isJSONRPCRequest, isJSONRPCResponse, JSONRPCMessage, JSONRPCMessageSchema, RequestId, SUPPORTED_PROTOCOL_VERSIONS, DEFAULT_NEGOTIATED_PROTOCOL_VERSION } from "../types.js";
 import getRawBody from "raw-body";
 import contentType from "content-type";
 import { randomUUID } from "node:crypto";
@@ -110,7 +110,7 @@ export class StreamableHTTPServerTransport implements Transport {
   private _eventStore?: EventStore;
   private _onsessioninitialized?: (sessionId: string) => void;
 
-  sessionId?: string | undefined;
+  sessionId?: string;
   onclose?: () => void;
   onerror?: (error: Error) => void;
   onmessage?: (message: JSONRPCMessage, extra?: { authInfo?: AuthInfo }) => void;
@@ -172,6 +172,9 @@ export class StreamableHTTPServerTransport implements Transport {
     if (!this.validateSession(req, res)) {
       return;
     }
+    if (!this.validateProtocolVersion(req, res)) {
+      return;
+    }
     // Handle resumability: check for Last-Event-ID header
     if (this._eventStore) {
       const lastEventId = req.headers['last-event-id'] as string | undefined;
@@ -378,11 +381,17 @@ export class StreamableHTTPServerTransport implements Transport {
         }
 
       }
-      // If an Mcp-Session-Id is returned by the server during initialization,
-      // clients using the Streamable HTTP transport MUST include it 
-      // in the Mcp-Session-Id header on all of their subsequent HTTP requests.
-      if (!isInitializationRequest && !this.validateSession(req, res)) {
-        return;
+      if (!isInitializationRequest) {
+        // If an Mcp-Session-Id is returned by the server during initialization,
+        // clients using the Streamable HTTP transport MUST include it 
+        // in the Mcp-Session-Id header on all of their subsequent HTTP requests.
+        if (!this.validateSession(req, res)) {
+          return;
+        }
+        // Mcp-Protocol-Version header is required for all requests after initialization.
+        if (!this.validateProtocolVersion(req, res)) {
+          return;
+        }
       }
 
 
@@ -457,6 +466,9 @@ export class StreamableHTTPServerTransport implements Transport {
     if (!this.validateSession(req, res)) {
       return;
     }
+    if (!this.validateProtocolVersion(req, res)) {
+      return;
+    }
     await this.close();
     res.writeHead(200).end();
   }
@@ -524,6 +536,25 @@ export class StreamableHTTPServerTransport implements Transport {
     return true;
   }
 
+  private validateProtocolVersion(req: IncomingMessage, res: ServerResponse): boolean {
+    let protocolVersion = req.headers["mcp-protocol-version"] ?? DEFAULT_NEGOTIATED_PROTOCOL_VERSION;
+    if (Array.isArray(protocolVersion)) {
+      protocolVersion = protocolVersion[protocolVersion.length - 1];
+    }
+
+    if (!SUPPORTED_PROTOCOL_VERSIONS.includes(protocolVersion)) {
+      res.writeHead(400).end(JSON.stringify({
+        jsonrpc: "2.0",
+        error: {
+          code: -32000,
+          message: `Bad Request: Unsupported protocol version (supported versions: ${SUPPORTED_PROTOCOL_VERSIONS.join(", ")})`
+        },
+        id: null
+      }));
+      return false;
+    }
+    return true;
+  }
 
   async close(): Promise<void> {
     // Close all SSE connections
diff --git a/src/server/title.test.ts b/src/server/title.test.ts
new file mode 100644
index 00000000..3f64570b
--- /dev/null
+++ b/src/server/title.test.ts
@@ -0,0 +1,236 @@
+import { Server } from "./index.js";
+import { Client } from "../client/index.js";
+import { InMemoryTransport } from "../inMemory.js";
+import { z } from "zod";
+import { McpServer, ResourceTemplate } from "./mcp.js";
+
+describe("Title field backwards compatibility", () => {
+  it("should work with tools that have title", async () => {
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+
+    const server = new McpServer(
+      { name: "test-server", version: "1.0.0" },
+      { capabilities: {} }
+    );
+
+    // Register tool with title
+    server.registerTool(
+      "test-tool",
+      {
+        title: "Test Tool Display Name",
+        description: "A test tool",
+        inputSchema: {
+          value: z.string()
+        }
+      },
+      async () => ({ content: [{ type: "text", text: "result" }] })
+    );
+
+    const client = new Client({ name: "test-client", version: "1.0.0" });
+
+    await server.server.connect(serverTransport);
+    await client.connect(clientTransport);
+
+    const tools = await client.listTools();
+    expect(tools.tools).toHaveLength(1);
+    expect(tools.tools[0].name).toBe("test-tool");
+    expect(tools.tools[0].title).toBe("Test Tool Display Name");
+    expect(tools.tools[0].description).toBe("A test tool");
+  });
+
+  it("should work with tools without title", async () => {
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+
+    const server = new McpServer(
+      { name: "test-server", version: "1.0.0" },
+      { capabilities: {} }
+    );
+
+    // Register tool without title
+    server.tool(
+      "test-tool",
+      "A test tool",
+      { value: z.string() },
+      async () => ({ content: [{ type: "text", text: "result" }] })
+    );
+
+    const client = new Client({ name: "test-client", version: "1.0.0" });
+
+    await server.server.connect(serverTransport);
+    await client.connect(clientTransport);
+
+    const tools = await client.listTools();
+    expect(tools.tools).toHaveLength(1);
+    expect(tools.tools[0].name).toBe("test-tool");
+    expect(tools.tools[0].title).toBeUndefined();
+    expect(tools.tools[0].description).toBe("A test tool");
+  });
+
+  it("should work with prompts that have title using update", async () => {
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+
+    const server = new McpServer(
+      { name: "test-server", version: "1.0.0" },
+      { capabilities: {} }
+    );
+
+    // Register prompt with title by updating after creation
+    const prompt = server.prompt(
+      "test-prompt",
+      "A test prompt",
+      async () => ({ messages: [{ role: "user", content: { type: "text", text: "test" } }] })
+    );
+    prompt.update({ title: "Test Prompt Display Name" });
+
+    const client = new Client({ name: "test-client", version: "1.0.0" });
+
+    await server.server.connect(serverTransport);
+    await client.connect(clientTransport);
+
+    const prompts = await client.listPrompts();
+    expect(prompts.prompts).toHaveLength(1);
+    expect(prompts.prompts[0].name).toBe("test-prompt");
+    expect(prompts.prompts[0].title).toBe("Test Prompt Display Name");
+    expect(prompts.prompts[0].description).toBe("A test prompt");
+  });
+
+  it("should work with prompts using registerPrompt", async () => {
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+
+    const server = new McpServer(
+      { name: "test-server", version: "1.0.0" },
+      { capabilities: {} }
+    );
+
+    // Register prompt with title using registerPrompt
+    server.registerPrompt(
+      "test-prompt",
+      {
+        title: "Test Prompt Display Name",
+        description: "A test prompt",
+        argsSchema: { input: z.string() }
+      },
+      async ({ input }) => ({
+        messages: [{
+          role: "user",
+          content: { type: "text", text: `test: ${input}` }
+        }]
+      })
+    );
+
+    const client = new Client({ name: "test-client", version: "1.0.0" });
+
+    await server.server.connect(serverTransport);
+    await client.connect(clientTransport);
+
+    const prompts = await client.listPrompts();
+    expect(prompts.prompts).toHaveLength(1);
+    expect(prompts.prompts[0].name).toBe("test-prompt");
+    expect(prompts.prompts[0].title).toBe("Test Prompt Display Name");
+    expect(prompts.prompts[0].description).toBe("A test prompt");
+    expect(prompts.prompts[0].arguments).toHaveLength(1);
+  });
+
+  it("should work with resources using registerResource", async () => {
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+
+    const server = new McpServer(
+      { name: "test-server", version: "1.0.0" },
+      { capabilities: {} }
+    );
+
+    // Register resource with title using registerResource
+    server.registerResource(
+      "test-resource",
+      "https://example.com/test",
+      {
+        title: "Test Resource Display Name",
+        description: "A test resource",
+        mimeType: "text/plain"
+      },
+      async () => ({
+        contents: [{
+          uri: "https://example.com/test",
+          text: "test content"
+        }]
+      })
+    );
+
+    const client = new Client({ name: "test-client", version: "1.0.0" });
+
+    await server.server.connect(serverTransport);
+    await client.connect(clientTransport);
+
+    const resources = await client.listResources();
+    expect(resources.resources).toHaveLength(1);
+    expect(resources.resources[0].name).toBe("test-resource");
+    expect(resources.resources[0].title).toBe("Test Resource Display Name");
+    expect(resources.resources[0].description).toBe("A test resource");
+    expect(resources.resources[0].mimeType).toBe("text/plain");
+  });
+
+  it("should work with dynamic resources using registerResource", async () => {
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+
+    const server = new McpServer(
+      { name: "test-server", version: "1.0.0" },
+      { capabilities: {} }
+    );
+
+    // Register dynamic resource with title using registerResource
+    server.registerResource(
+      "user-profile",
+      new ResourceTemplate("users://{userId}/profile", { list: undefined }),
+      {
+        title: "User Profile",
+        description: "User profile information"
+      },
+      async (uri, { userId }, _extra) => ({
+        contents: [{
+          uri: uri.href,
+          text: `Profile data for user ${userId}`
+        }]
+      })
+    );
+
+    const client = new Client({ name: "test-client", version: "1.0.0" });
+
+    await server.server.connect(serverTransport);
+    await client.connect(clientTransport);
+
+    const resourceTemplates = await client.listResourceTemplates();
+    expect(resourceTemplates.resourceTemplates).toHaveLength(1);
+    expect(resourceTemplates.resourceTemplates[0].name).toBe("user-profile");
+    expect(resourceTemplates.resourceTemplates[0].title).toBe("User Profile");
+    expect(resourceTemplates.resourceTemplates[0].description).toBe("User profile information");
+    expect(resourceTemplates.resourceTemplates[0].uriTemplate).toBe("users://{userId}/profile");
+
+    // Test reading the resource
+    const readResult = await client.readResource({ uri: "users://123/profile" });
+    expect(readResult.contents).toHaveLength(1);
+    expect(readResult.contents[0].text).toBe("Profile data for user 123");
+  });
+
+  it("should support serverInfo with title", async () => {
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+
+    const server = new Server(
+      {
+        name: "test-server",
+        version: "1.0.0",
+        title: "Test Server Display Name"
+      },
+      { capabilities: {} }
+    );
+
+    const client = new Client({ name: "test-client", version: "1.0.0" });
+
+    await server.connect(serverTransport);
+    await client.connect(clientTransport);
+
+    const serverInfo = client.getServerVersion();
+    expect(serverInfo?.name).toBe("test-server");
+    expect(serverInfo?.version).toBe("1.0.0");
+    expect(serverInfo?.title).toBe("Test Server Display Name");
+  });
+});
\ No newline at end of file
diff --git a/src/shared/metadataUtils.ts b/src/shared/metadataUtils.ts
new file mode 100644
index 00000000..410827a5
--- /dev/null
+++ b/src/shared/metadataUtils.ts
@@ -0,0 +1,36 @@
+import { BaseMetadata } from "../types.js";
+
+/**
+ * Utilities for working with BaseMetadata objects.
+ */
+
+/**
+ * Gets the display name for an object with BaseMetadata.
+ * For tools, the precedence is: title → annotations.title → name
+ * For other objects: title → name
+ * This implements the spec requirement: "if no title is provided, name should be used for display purposes"
+ */
+export function getDisplayName(metadata: BaseMetadata): string {
+  // First check for title (not undefined and not empty string)
+  if (metadata.title !== undefined && metadata.title !== '') {
+    return metadata.title;
+  }
+  
+  // Then check for annotations.title (only present in Tool objects)
+  if ('annotations' in metadata) {
+    const metadataWithAnnotations = metadata as BaseMetadata & { annotations?: { title?: string } };
+    if (metadataWithAnnotations.annotations?.title) {
+      return metadataWithAnnotations.annotations.title;
+    }
+  }
+  
+  // Finally fall back to name
+  return metadata.name;
+}
+
+/**
+ * Checks if an object has a custom title different from its name.
+ */
+export function hasCustomTitle(metadata: BaseMetadata): boolean {
+  return metadata.title !== undefined && metadata.title !== metadata.name;
+}
\ No newline at end of file
diff --git a/src/shared/transport.ts b/src/shared/transport.ts
index fe0a60e6..b75e072e 100644
--- a/src/shared/transport.ts
+++ b/src/shared/transport.ts
@@ -75,4 +75,9 @@ export interface Transport {
    * The session ID generated for this connection.
    */
   sessionId?: string;
+
+  /**
+   * Sets the protocol version used for the connection (called when the initialize response is received).
+   */
+  setProtocolVersion?: (version: string) => void;
 }
diff --git a/src/types.test.ts b/src/types.test.ts
index 0fbc003d..bc109110 100644
--- a/src/types.test.ts
+++ b/src/types.test.ts
@@ -1,4 +1,12 @@
-import { LATEST_PROTOCOL_VERSION, SUPPORTED_PROTOCOL_VERSIONS } from "./types.js";
+import {
+    LATEST_PROTOCOL_VERSION,
+    SUPPORTED_PROTOCOL_VERSIONS,
+    ResourceLinkSchema,
+    ContentBlockSchema,
+    PromptMessageSchema,
+    CallToolResultSchema,
+    CompleteRequestSchema
+} from "./types.js";
 
 describe("Types", () => {
 
@@ -14,4 +22,293 @@ describe("Types", () => {
         expect(SUPPORTED_PROTOCOL_VERSIONS).toContain("2024-10-07");
     });
 
+    describe("ResourceLink", () => {
+        test("should validate a minimal ResourceLink", () => {
+            const resourceLink = {
+                type: "resource_link",
+                uri: "file:///path/to/file.txt",
+                name: "file.txt"
+            };
+
+            const result = ResourceLinkSchema.safeParse(resourceLink);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.type).toBe("resource_link");
+                expect(result.data.uri).toBe("file:///path/to/file.txt");
+                expect(result.data.name).toBe("file.txt");
+            }
+        });
+
+        test("should validate a ResourceLink with all optional fields", () => {
+            const resourceLink = {
+                type: "resource_link",
+                uri: "https://example.com/resource",
+                name: "Example Resource",
+                title: "A comprehensive example resource",
+                description: "This resource demonstrates all fields",
+                mimeType: "text/plain",
+                _meta: { custom: "metadata" }
+            };
+
+            const result = ResourceLinkSchema.safeParse(resourceLink);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.title).toBe("A comprehensive example resource");
+                expect(result.data.description).toBe("This resource demonstrates all fields");
+                expect(result.data.mimeType).toBe("text/plain");
+                expect(result.data._meta).toEqual({ custom: "metadata" });
+            }
+        });
+
+        test("should fail validation for invalid type", () => {
+            const invalidResourceLink = {
+                type: "invalid_type",
+                uri: "file:///path/to/file.txt",
+                name: "file.txt"
+            };
+
+            const result = ResourceLinkSchema.safeParse(invalidResourceLink);
+            expect(result.success).toBe(false);
+        });
+
+        test("should fail validation for missing required fields", () => {
+            const invalidResourceLink = {
+                type: "resource_link",
+                uri: "file:///path/to/file.txt"
+                // missing name
+            };
+
+            const result = ResourceLinkSchema.safeParse(invalidResourceLink);
+            expect(result.success).toBe(false);
+        });
+    });
+
+    describe("ContentBlock", () => {
+        test("should validate text content", () => {
+            const textContent = {
+                type: "text",
+                text: "Hello, world!"
+            };
+
+            const result = ContentBlockSchema.safeParse(textContent);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.type).toBe("text");
+            }
+        });
+
+        test("should validate image content", () => {
+            const imageContent = {
+                type: "image",
+                data: "aGVsbG8=", // base64 encoded "hello"
+                mimeType: "image/png"
+            };
+
+            const result = ContentBlockSchema.safeParse(imageContent);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.type).toBe("image");
+            }
+        });
+
+        test("should validate audio content", () => {
+            const audioContent = {
+                type: "audio",
+                data: "aGVsbG8=", // base64 encoded "hello"
+                mimeType: "audio/mp3"
+            };
+
+            const result = ContentBlockSchema.safeParse(audioContent);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.type).toBe("audio");
+            }
+        });
+
+        test("should validate resource link content", () => {
+            const resourceLink = {
+                type: "resource_link",
+                uri: "file:///path/to/file.txt",
+                name: "file.txt",
+                mimeType: "text/plain"
+            };
+
+            const result = ContentBlockSchema.safeParse(resourceLink);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.type).toBe("resource_link");
+            }
+        });
+
+        test("should validate embedded resource content", () => {
+            const embeddedResource = {
+                type: "resource",
+                resource: {
+                    uri: "file:///path/to/file.txt",
+                    mimeType: "text/plain",
+                    text: "File contents"
+                }
+            };
+
+            const result = ContentBlockSchema.safeParse(embeddedResource);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.type).toBe("resource");
+            }
+        });
+    });
+
+    describe("PromptMessage with ContentBlock", () => {
+        test("should validate prompt message with resource link", () => {
+            const promptMessage = {
+                role: "assistant",
+                content: {
+                    type: "resource_link",
+                    uri: "file:///project/src/main.rs",
+                    name: "main.rs",
+                    description: "Primary application entry point",
+                    mimeType: "text/x-rust"
+                }
+            };
+
+            const result = PromptMessageSchema.safeParse(promptMessage);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.content.type).toBe("resource_link");
+            }
+        });
+    });
+
+    describe("CallToolResult with ContentBlock", () => {
+        test("should validate tool result with resource links", () => {
+            const toolResult = {
+                content: [
+                    {
+                        type: "text",
+                        text: "Found the following files:"
+                    },
+                    {
+                        type: "resource_link",
+                        uri: "file:///project/src/main.rs",
+                        name: "main.rs",
+                        description: "Primary application entry point",
+                        mimeType: "text/x-rust"
+                    },
+                    {
+                        type: "resource_link",
+                        uri: "file:///project/src/lib.rs",
+                        name: "lib.rs",
+                        description: "Library exports",
+                        mimeType: "text/x-rust"
+                    }
+                ]
+            };
+
+            const result = CallToolResultSchema.safeParse(toolResult);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.content).toHaveLength(3);
+                expect(result.data.content[0].type).toBe("text");
+                expect(result.data.content[1].type).toBe("resource_link");
+                expect(result.data.content[2].type).toBe("resource_link");
+            }
+        });
+
+        test("should validate empty content array with default", () => {
+            const toolResult = {};
+
+            const result = CallToolResultSchema.safeParse(toolResult);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.content).toEqual([]);
+            }
+        });
+    });
+
+    describe("CompleteRequest", () => {
+        test("should validate a CompleteRequest without resolved field", () => {
+            const request = {
+                method: "completion/complete",
+                params: {
+                    ref: { type: "ref/prompt", name: "greeting" },
+                    argument: { name: "name", value: "A" }
+                }
+            };
+
+            const result = CompleteRequestSchema.safeParse(request);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.method).toBe("completion/complete");
+                expect(result.data.params.ref.type).toBe("ref/prompt");
+                expect(result.data.params.context).toBeUndefined();
+            }
+        });
+
+        test("should validate a CompleteRequest with resolved field", () => {
+            const request = {
+                method: "completion/complete",
+                params: {
+                    ref: { type: "ref/resource", uri: "github://repos/{owner}/{repo}" },
+                    argument: { name: "repo", value: "t" },
+                    context: {
+                        arguments: {
+                            "{owner}": "microsoft"
+                        }
+                    }
+                }
+            };
+
+            const result = CompleteRequestSchema.safeParse(request);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.params.context?.arguments).toEqual({
+                    "{owner}": "microsoft"
+                });
+            }
+        });
+
+        test("should validate a CompleteRequest with empty resolved field", () => {
+            const request = {
+                method: "completion/complete",
+                params: {
+                    ref: { type: "ref/prompt", name: "test" },
+                    argument: { name: "arg", value: "" },
+                    context: {
+                        arguments: {}
+                    }
+                }
+            };
+
+            const result = CompleteRequestSchema.safeParse(request);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.params.context?.arguments).toEqual({});
+            }
+        });
+
+        test("should validate a CompleteRequest with multiple resolved variables", () => {
+            const request = {
+                method: "completion/complete",
+                params: {
+                    ref: { type: "ref/resource", uri: "api://v1/{tenant}/{resource}/{id}" },
+                    argument: { name: "id", value: "123" },
+                    context: {
+                        arguments: {
+                            "{tenant}": "acme-corp",
+                            "{resource}": "users"
+                        }
+                    }
+                }
+            };
+
+            const result = CompleteRequestSchema.safeParse(request);
+            expect(result.success).toBe(true);
+            if (result.success) {
+                expect(result.data.params.context?.arguments).toEqual({
+                    "{tenant}": "acme-corp",
+                    "{resource}": "users"
+                });
+            }
+        });
+    });
 });
diff --git a/src/types.ts b/src/types.ts
index e5a544b5..b77a27bf 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -1,6 +1,7 @@
 import { z, ZodTypeAny } from "zod";
 
 export const LATEST_PROTOCOL_VERSION = "2025-03-26";
+export const DEFAULT_NEGOTIATED_PROTOCOL_VERSION = "2025-03-26";
 export const SUPPORTED_PROTOCOL_VERSIONS = [
   LATEST_PROTOCOL_VERSION,
   "2024-11-05",
@@ -43,8 +44,8 @@ export const RequestSchema = z.object({
 const BaseNotificationParamsSchema = z
   .object({
     /**
-     * This parameter name is reserved by MCP to allow clients and servers to attach additional metadata to their notifications.
-     */
+     * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+    */
     _meta: z.optional(z.object({}).passthrough()),
   })
   .passthrough();
@@ -57,8 +58,8 @@ export const NotificationSchema = z.object({
 export const ResultSchema = z
   .object({
     /**
-     * This result property is reserved by the protocol to allow clients and servers to attach additional metadata to their responses.
-     */
+     * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+    */
     _meta: z.optional(z.object({}).passthrough()),
   })
   .passthrough();
@@ -194,16 +195,33 @@ export const CancelledNotificationSchema = NotificationSchema.extend({
   }),
 });
 
+/* Base Metadata */
+/**
+ * Base metadata interface for common properties across resources, tools, prompts, and implementations.
+ */
+export const BaseMetadataSchema = z
+  .object({
+    /** Intended for programmatic or logical use, but used as a display name in past specs or fallback */
+    name: z.string(),
+    /**
+    * Intended for UI and end-user contexts — optimized to be human-readable and easily understood,
+    * even by those unfamiliar with domain-specific terminology.
+    *
+    * If not provided, the name should be used for display (except for Tool,
+    * where `annotations.title` should be given precedence over using `name`,
+    * if present).
+    */
+    title: z.optional(z.string()),
+  })
+  .passthrough();
+
 /* Initialization */
 /**
  * Describes the name and version of an MCP implementation.
  */
-export const ImplementationSchema = z
-  .object({
-    name: z.string(),
-    version: z.string(),
-  })
-  .passthrough();
+export const ImplementationSchema = BaseMetadataSchema.extend({
+  version: z.string(),
+});
 
 /**
  * Capabilities a client may support. Known capabilities are defined here, in this schema, but this is not a closed set: any client can define its own, additional capabilities.
@@ -421,6 +439,10 @@ export const ResourceContentsSchema = z
      * The MIME type of this resource, if known.
      */
     mimeType: z.optional(z.string()),
+    /**
+     * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+     */
+    _meta: z.optional(z.object({}).passthrough()),
   })
   .passthrough();
 
@@ -441,64 +463,56 @@ export const BlobResourceContentsSchema = ResourceContentsSchema.extend({
 /**
  * A known resource that the server is capable of reading.
  */
-export const ResourceSchema = z
-  .object({
-    /**
-     * The URI of this resource.
-     */
-    uri: z.string(),
+export const ResourceSchema = BaseMetadataSchema.extend({
+  /**
+   * The URI of this resource.
+   */
+  uri: z.string(),
 
-    /**
-     * A human-readable name for this resource.
-     *
-     * This can be used by clients to populate UI elements.
-     */
-    name: z.string(),
+  /**
+   * A description of what this resource represents.
+   *
+   * This can be used by clients to improve the LLM's understanding of available resources. It can be thought of like a "hint" to the model.
+   */
+  description: z.optional(z.string()),
 
-    /**
-     * A description of what this resource represents.
-     *
-     * This can be used by clients to improve the LLM's understanding of available resources. It can be thought of like a "hint" to the model.
-     */
-    description: z.optional(z.string()),
+  /**
+   * The MIME type of this resource, if known.
+   */
+  mimeType: z.optional(z.string()),
 
-    /**
-     * The MIME type of this resource, if known.
-     */
-    mimeType: z.optional(z.string()),
-  })
-  .passthrough();
+  /**
+   * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+  */
+  _meta: z.optional(z.object({}).passthrough()),
+});
 
 /**
  * A template description for resources available on the server.
  */
-export const ResourceTemplateSchema = z
-  .object({
-    /**
-     * A URI template (according to RFC 6570) that can be used to construct resource URIs.
-     */
-    uriTemplate: z.string(),
+export const ResourceTemplateSchema = BaseMetadataSchema.extend({
+  /**
+   * A URI template (according to RFC 6570) that can be used to construct resource URIs.
+   */
+  uriTemplate: z.string(),
 
-    /**
-     * A human-readable name for the type of resource this template refers to.
-     *
-     * This can be used by clients to populate UI elements.
-     */
-    name: z.string(),
+  /**
+   * A description of what this template is for.
+   *
+   * This can be used by clients to improve the LLM's understanding of available resources. It can be thought of like a "hint" to the model.
+   */
+  description: z.optional(z.string()),
 
-    /**
-     * A description of what this template is for.
-     *
-     * This can be used by clients to improve the LLM's understanding of available resources. It can be thought of like a "hint" to the model.
-     */
-    description: z.optional(z.string()),
+  /**
+   * The MIME type for all resources that match this template. This should only be included if all resources matching this template have the same type.
+   */
+  mimeType: z.optional(z.string()),
 
-    /**
-     * The MIME type for all resources that match this template. This should only be included if all resources matching this template have the same type.
-     */
-    mimeType: z.optional(z.string()),
-  })
-  .passthrough();
+  /**
+   * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+  */
+  _meta: z.optional(z.object({}).passthrough()),
+});
 
 /**
  * Sent from the client to request a list of resources the server has.
@@ -622,22 +636,20 @@ export const PromptArgumentSchema = z
 /**
  * A prompt or prompt template that the server offers.
  */
-export const PromptSchema = z
-  .object({
-    /**
-     * The name of the prompt or prompt template.
-     */
-    name: z.string(),
-    /**
-     * An optional description of what this prompt provides
-     */
-    description: z.optional(z.string()),
-    /**
-     * A list of arguments to use for templating the prompt.
-     */
-    arguments: z.optional(z.array(PromptArgumentSchema)),
-  })
-  .passthrough();
+export const PromptSchema = BaseMetadataSchema.extend({
+  /**
+   * An optional description of what this prompt provides
+   */
+  description: z.optional(z.string()),
+  /**
+   * A list of arguments to use for templating the prompt.
+   */
+  arguments: z.optional(z.array(PromptArgumentSchema)),
+  /**
+   * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+   */
+  _meta: z.optional(z.object({}).passthrough()),
+});
 
 /**
  * Sent from the client to request a list of prompts and prompt templates the server has.
@@ -680,6 +692,11 @@ export const TextContentSchema = z
      * The text content of the message.
      */
     text: z.string(),
+
+    /**
+     * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+    */
+    _meta: z.optional(z.object({}).passthrough()),
   })
   .passthrough();
 
@@ -697,6 +714,11 @@ export const ImageContentSchema = z
      * The MIME type of the image. Different providers may support different image types.
      */
     mimeType: z.string(),
+
+    /**
+     * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+    */
+    _meta: z.optional(z.object({}).passthrough()),
   })
   .passthrough();
 
@@ -714,6 +736,11 @@ export const AudioContentSchema = z
      * The MIME type of the audio. Different providers may support different audio types.
      */
     mimeType: z.string(),
+
+    /**
+     * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+    */
+    _meta: z.optional(z.object({}).passthrough()),
   })
   .passthrough();
 
@@ -724,21 +751,40 @@ export const EmbeddedResourceSchema = z
   .object({
     type: z.literal("resource"),
     resource: z.union([TextResourceContentsSchema, BlobResourceContentsSchema]),
+    /**
+     * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+     */
+    _meta: z.optional(z.object({}).passthrough()),
   })
   .passthrough();
 
+/**
+ * A resource that the server is capable of reading, included in a prompt or tool call result.
+ *
+ * Note: resource links returned by tools are not guaranteed to appear in the results of `resources/list` requests.
+ */
+export const ResourceLinkSchema = ResourceSchema.extend({
+  type: z.literal("resource_link"),
+});
+
+/**
+ * A content block that can be used in prompts and tool results.
+ */
+export const ContentBlockSchema = z.union([
+  TextContentSchema,
+  ImageContentSchema,
+  AudioContentSchema,
+  ResourceLinkSchema,
+  EmbeddedResourceSchema,
+]);
+
 /**
  * Describes a message returned as part of a prompt.
  */
 export const PromptMessageSchema = z
   .object({
     role: z.enum(["user", "assistant"]),
-    content: z.union([
-      TextContentSchema,
-      ImageContentSchema,
-      AudioContentSchema,
-      EmbeddedResourceSchema,
-    ]),
+    content: ContentBlockSchema,
   })
   .passthrough();
 
@@ -820,44 +866,43 @@ export const ToolAnnotationsSchema = z
 /**
  * Definition for a tool the client can call.
  */
-export const ToolSchema = z
-  .object({
-    /**
-     * The name of the tool.
-     */
-    name: z.string(),
-    /**
-     * A human-readable description of the tool.
-     */
-    description: z.optional(z.string()),
-    /**
-     * A JSON Schema object defining the expected parameters for the tool.
-     */
-    inputSchema: z
-      .object({
-        type: z.literal("object"),
-        properties: z.optional(z.object({}).passthrough()),
-        required: z.optional(z.array(z.string())),
-      })
-      .passthrough(),
-    /**
-     * An optional JSON Schema object defining the structure of the tool's output returned in 
-     * the structuredContent field of a CallToolResult.
-     */
-    outputSchema: z.optional(
-      z.object({
-        type: z.literal("object"),
-        properties: z.optional(z.object({}).passthrough()),
-        required: z.optional(z.array(z.string())),
-      })
+export const ToolSchema = BaseMetadataSchema.extend({
+  /**
+   * A human-readable description of the tool.
+   */
+  description: z.optional(z.string()),
+  /**
+   * A JSON Schema object defining the expected parameters for the tool.
+   */
+  inputSchema: z
+    .object({
+      type: z.literal("object"),
+      properties: z.optional(z.object({}).passthrough()),
+      required: z.optional(z.array(z.string())),
+    })
+    .passthrough(),
+  /**
+   * An optional JSON Schema object defining the structure of the tool's output returned in 
+   * the structuredContent field of a CallToolResult.
+   */
+  outputSchema: z.optional(
+    z.object({
+      type: z.literal("object"),
+      properties: z.optional(z.object({}).passthrough()),
+      required: z.optional(z.array(z.string())),
+    })
       .passthrough()
-    ),
-    /**
-     * Optional additional tool information.
-     */
-    annotations: z.optional(ToolAnnotationsSchema),
-  })
-  .passthrough();
+  ),
+  /**
+   * Optional additional tool information.
+   */
+  annotations: z.optional(ToolAnnotationsSchema),
+
+  /**
+   * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+  */
+  _meta: z.optional(z.object({}).passthrough()),
+});
 
 /**
  * Sent from the client to request a list of tools the server has.
@@ -883,13 +928,7 @@ export const CallToolResultSchema = ResultSchema.extend({
    * If the Tool does not define an outputSchema, this field MUST be present in the result.
    * For backwards compatibility, this field is always present, but it may be empty.
    */
-  content: z.array(
-    z.union([
-      TextContentSchema,
-      ImageContentSchema,
-      AudioContentSchema,
-      EmbeddedResourceSchema,
-    ])).default([]),
+  content: z.array(ContentBlockSchema).default([]),
 
   /**
    * An object containing structured tool output.
@@ -1197,7 +1236,7 @@ export const ElicitResultSchema = ResultSchema.extend({
 /**
  * A reference to a resource or resource template definition.
  */
-export const ResourceReferenceSchema = z
+export const ResourceTemplateReferenceSchema = z
   .object({
     type: z.literal("ref/resource"),
     /**
@@ -1207,6 +1246,11 @@ export const ResourceReferenceSchema = z
   })
   .passthrough();
 
+/**
+ * @deprecated Use ResourceTemplateReferenceSchema instead
+ */
+export const ResourceReferenceSchema = ResourceTemplateReferenceSchema;
+
 /**
  * Identifies a prompt.
  */
@@ -1226,7 +1270,7 @@ export const PromptReferenceSchema = z
 export const CompleteRequestSchema = RequestSchema.extend({
   method: z.literal("completion/complete"),
   params: BaseRequestParamsSchema.extend({
-    ref: z.union([PromptReferenceSchema, ResourceReferenceSchema]),
+    ref: z.union([PromptReferenceSchema, ResourceTemplateReferenceSchema]),
     /**
      * The argument's information
      */
@@ -1242,6 +1286,14 @@ export const CompleteRequestSchema = RequestSchema.extend({
         value: z.string(),
       })
       .passthrough(),
+    context: z.optional(
+      z.object({
+        /**
+         * Previously-resolved variables in a URI template or prompt.
+         */
+        arguments: z.optional(z.record(z.string(), z.string())),
+      })
+    ),
   }),
 });
 
@@ -1281,6 +1333,11 @@ export const RootSchema = z
      * An optional name for the root.
      */
     name: z.optional(z.string()),
+
+    /**
+     * Reserved by MCP for protocol-level metadata; implementations must not make assumptions about its contents.
+    */
+    _meta: z.optional(z.object({}).passthrough()),
   })
   .passthrough();
 
@@ -1413,6 +1470,9 @@ export type EmptyResult = Infer<typeof EmptyResultSchema>;
 /* Cancellation */
 export type CancelledNotification = Infer<typeof CancelledNotificationSchema>;
 
+/* Base Metadata */
+export type BaseMetadata = Infer<typeof BaseMetadataSchema>;
+
 /* Initialization */
 export type Implementation = Infer<typeof ImplementationSchema>;
 export type ClientCapabilities = Infer<typeof ClientCapabilitiesSchema>;
@@ -1459,6 +1519,8 @@ export type TextContent = Infer<typeof TextContentSchema>;
 export type ImageContent = Infer<typeof ImageContentSchema>;
 export type AudioContent = Infer<typeof AudioContentSchema>;
 export type EmbeddedResource = Infer<typeof EmbeddedResourceSchema>;
+export type ResourceLink = Infer<typeof ResourceLinkSchema>;
+export type ContentBlock = Infer<typeof ContentBlockSchema>;
 export type PromptMessage = Infer<typeof PromptMessageSchema>;
 export type GetPromptResult = Infer<typeof GetPromptResultSchema>;
 export type PromptListChangedNotification = Infer<typeof PromptListChangedNotificationSchema>;
@@ -1493,7 +1555,11 @@ export type ElicitRequest = Infer<typeof ElicitRequestSchema>;
 export type ElicitResult = Infer<typeof ElicitResultSchema>;
 
 /* Autocomplete */
-export type ResourceReference = Infer<typeof ResourceReferenceSchema>;
+export type ResourceTemplateReference = Infer<typeof ResourceTemplateReferenceSchema>;
+/**
+ * @deprecated Use ResourceTemplateReference instead
+ */
+export type ResourceReference = ResourceTemplateReference;
 export type PromptReference = Infer<typeof PromptReferenceSchema>;
 export type CompleteRequest = Infer<typeof CompleteRequestSchema>;
 export type CompleteResult = Infer<typeof CompleteResultSchema>;