feat: port to SDK v2 via concrete Protocol (typescript-sdk#1891)

package.json

@@ -76,7 +76,6 @@
   "author": "Olivier Chafik",
   "devDependencies": {
     "@boneskull/typedoc-plugin-mermaid": "^0.2.0",
-    "@modelcontextprotocol/sdk": "^1.29.0",
     "@playwright/test": "1.57.0",
     "@types/bun": "^1.3.2",
     "@types/node": "20.19.27",
@@ -107,7 +106,6 @@
     "zod": "^4.1.13"
   },
   "peerDependencies": {
-    "@modelcontextprotocol/sdk": "^1.29.0",
     "react": "^17.0.0 || ^18.0.0 || ^19.0.0",
     "react-dom": "^17.0.0 || ^18.0.0 || ^19.0.0",
     "zod": "^3.25.0 || ^4.0.0"
@@ -125,5 +123,11 @@
     "seroval-plugins": "1.4.2",
     "solid-js": "1.9.10",
     "@types/node": "20.19.27"
+  },
+  "dependencies": {
+    "@modelcontextprotocol/client": "file:../../../../../tmp/modelcontextprotocol-client-2.0.0-alpha.2.tgz",
+    "@modelcontextprotocol/express": "file:../../../../../tmp/modelcontextprotocol-express-2.0.0-alpha.2.tgz",
+    "@modelcontextprotocol/node": "file:../../../../../tmp/modelcontextprotocol-node-2.0.0-alpha.2.tgz",
+    "@modelcontextprotocol/server": "file:../../../../../tmp/modelcontextprotocol-server-2.0.0-alpha.2.tgz"
   }
 }

scripts/generate-schemas.ts

@@ -187,20 +187,24 @@ function postProcess(content: string): string {
   // 1. Rewrite to zod/v4 and add MCP SDK schema imports.
   // zod/v4 aligns with the SDK's own zod import — composing v3 and v4
   // schema instances throws at parse time. See header comment for details.
-  const mcpImports = EXTERNAL_TYPE_SCHEMAS.join(",\n  ");
+  const typeImports = EXTERNAL_TYPE_SCHEMAS.map((s) =>
+    s.replace(/Schema$/, ""),
+  ).join(",\n  ");
   content = content.replace(
     'import { z } from "zod";',
     `import { z } from "zod/v4";
-import {
-  ${mcpImports},
-} from "@modelcontextprotocol/sdk/types.js";`,
+import { isSpecType } from "@modelcontextprotocol/client";
+import type {
+  ${typeImports},
+} from "@modelcontextprotocol/client";`,
   );
 
-  // 2. Remove z.any() placeholders for external types (now imported from MCP SDK)
+  // 2. Replace z.any() placeholders for external types with isSpecType-backed z.custom()
   for (const schema of EXTERNAL_TYPE_SCHEMAS) {
+    const typeName = schema.replace(/Schema$/, "");
     content = content.replace(
-      new RegExp(`(?:export )?const ${schema} = z\\.any\\(\\);\\n?`, "g"),
-      "",
+      new RegExp(`((?:export )?const ${schema}) = z\\.any\\(\\);`, "g"),
+      `$1 = z.custom<${typeName}>((v) => isSpecType("${typeName}", v));`,
     );
   }
 

src/app-bridge.examples.ts

@@ -7,15 +7,15 @@
  * @module
  */
 
-import { Client } from "@modelcontextprotocol/sdk/client/index.js";
-import type { Transport } from "@modelcontextprotocol/sdk/shared/transport.js";
+import { Client } from "@modelcontextprotocol/client";
+import type { Transport } from "@modelcontextprotocol/client";
 import {
   CallToolResult,
   CallToolResultSchema,
   ListResourcesResultSchema,
   ReadResourceResultSchema,
   ListPromptsResultSchema,
-} from "@modelcontextprotocol/sdk/types.js";
+} from "@modelcontextprotocol/client";
 import { AppBridge, PostMessageTransport } from "./app-bridge.js";
 import type { McpUiDisplayMode } from "./types.js";
 

src/app-bridge.test.ts

@@ -1,7 +1,9 @@
 import { describe, it, expect, beforeEach, afterEach } from "bun:test";
-import { InMemoryTransport } from "@modelcontextprotocol/sdk/inMemory.js";
-import type { Client } from "@modelcontextprotocol/sdk/client/index.js";
-import type { ServerCapabilities } from "@modelcontextprotocol/sdk/types.js";
+import {
+  InMemoryTransport,
+  type Client,
+  type ServerCapabilities,
+} from "@modelcontextprotocol/client";
 import {
   EmptyResultSchema,
   ListPromptsResultSchema,
@@ -11,7 +13,7 @@ import {
   ReadResourceResultSchema,
   ResourceListChangedNotificationSchema,
   ToolListChangedNotificationSchema,
-} from "@modelcontextprotocol/sdk/types.js";
+} from "./sdk-schemas";
 
 import { App } from "./app";
 import {
@@ -680,10 +682,7 @@ describe("App <-> AppBridge integration", () => {
       await app.connect(appTransport);
 
       // Bridge can send ping via the protocol's request method
-      const result = await bridge.request(
-        { method: "ping", params: {} },
-        EmptyResultSchema,
-      );
+      const result = await bridge.request("ping", {}, EmptyResultSchema);
 
       expect(result).toEqual({});
     });
@@ -795,7 +794,8 @@ describe("App <-> AppBridge integration", () => {
 
       // App sends resources/list request via the protocol's request method
       const result = await app.request(
-        { method: "resources/list", params: requestParams },
+        "resources/list",
+        requestParams,
         ListResourcesResultSchema,
       );
 
@@ -839,7 +839,8 @@ describe("App <-> AppBridge integration", () => {
       await app.connect(appTransport);
 
       const result = await app.request(
-        { method: "resources/read", params: requestParams },
+        "resources/read",
+        requestParams,
         ReadResourceResultSchema,
       );
 
@@ -890,7 +891,8 @@ describe("App <-> AppBridge integration", () => {
       await app.connect(appTransport);
 
       const result = await app.request(
-        { method: "resources/templates/list", params: requestParams },
+        "resources/templates/list",
+        requestParams,
         ListResourceTemplatesResultSchema,
       );
 
@@ -913,7 +915,8 @@ describe("App <-> AppBridge integration", () => {
       await app.connect(appTransport);
 
       const result = await app.request(
-        { method: "prompts/list", params: requestParams },
+        "prompts/list",
+        requestParams,
         ListPromptsResultSchema,
       );
 
@@ -1370,13 +1373,11 @@ describe("isToolVisibilityAppOnly", () => {
         testHostCapabilities,
       );
       bridge2.setRequestHandler(
-        // @ts-expect-error — exercising throw path with raw schema
         { shape: { method: { value: "test/method" } } },
         () => ({}),
       );
       expect(() => {
         bridge2.setRequestHandler(
-          // @ts-expect-error — exercising throw path with raw schema
           { shape: { method: { value: "test/method" } } },
           () => ({}),
         );
@@ -1388,7 +1389,6 @@ describe("isToolVisibilityAppOnly", () => {
       app2.addEventListener("toolinput", () => {});
       expect(() => {
         app2.setNotificationHandler(
-          // @ts-expect-error — exercising throw path with raw schema
           {
             shape: { method: { value: "ui/notifications/tool-input" } },
           },