From 02236ca3e7fa85878410f65d450b91aa102c16c4 Mon Sep 17 00:00:00 2001
From: Konstantin Konstantinov <konstantin@mach5technology.com>
Date: Sun, 1 Mar 2026 01:27:40 +0200
Subject: [PATCH 1/4] ci: add Bun and Deno integration tests

Add integration tests that run MCP server/client round-trips natively
on Bun and Deno using their respective test runners, verifying the SDK
works across runtimes beyond Node.js.

- Add bun.test.ts using bun:test + Bun.serve()
- Add deno.test.ts using Deno.test + Deno.serve() + node:assert
- Add deno.json with nodeModulesDir: "manual" for pnpm compatibility
- Add test-runtimes CI job (Bun 1.x + Deno v2.x matrix)
- Gate publish job on test-runtimes passing
- Exclude runtime-specific tests from vitest and tsconfig

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 .github/workflows/main.yml                | 38 +++++++++++++++-
 test/integration/deno.json                |  3 ++
 test/integration/package.json             |  4 +-
 test/integration/test/server/bun.test.ts  | 54 +++++++++++++++++++++++
 test/integration/test/server/deno.test.ts | 50 +++++++++++++++++++++
 test/integration/tsconfig.json            |  2 +-
 test/integration/vitest.config.js         |  7 ++-
 7 files changed, 154 insertions(+), 4 deletions(-)
 create mode 100644 test/integration/deno.json
 create mode 100644 test/integration/test/server/bun.test.ts
 create mode 100644 test/integration/test/server/deno.test.ts

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index baa1b6680..4fd4d35e9 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -58,11 +58,47 @@ jobs:
 
             - run: pnpm test:all
 
+    test-runtimes:
+        runs-on: ubuntu-latest
+        strategy:
+            fail-fast: false
+            matrix:
+                include:
+                    - runtime: bun
+                      version: "1.x"
+                    - runtime: deno
+                      version: v2.x
+        steps:
+            - uses: actions/checkout@v6
+            - name: Install pnpm
+              uses: pnpm/action-setup@v4
+              with:
+                  run_install: false
+            - uses: actions/setup-node@v6
+              with:
+                  node-version: 24
+                  cache: pnpm
+                  cache-dependency-path: pnpm-lock.yaml
+            - name: Set up Bun
+              if: matrix.runtime == 'bun'
+              uses: oven-sh/setup-bun@v2
+              with:
+                  bun-version: ${{ matrix.version }}
+            - name: Set up Deno
+              if: matrix.runtime == 'deno'
+              uses: denoland/setup-deno@v2
+              with:
+                  deno-version: ${{ matrix.version }}
+            - run: pnpm install
+            - run: pnpm build:all
+            - name: Run ${{ matrix.runtime }} integration tests
+              run: pnpm --filter @modelcontextprotocol/test-integration test:integration:${{ matrix.runtime }}
+
     publish:
         runs-on: ubuntu-latest
         if: github.event_name == 'release'
         environment: release
-        needs: [build, test]
+        needs: [build, test, test-runtimes]
 
         permissions:
             contents: read
diff --git a/test/integration/deno.json b/test/integration/deno.json
new file mode 100644
index 000000000..fde86a1ef
--- /dev/null
+++ b/test/integration/deno.json
@@ -0,0 +1,3 @@
+{
+  "nodeModulesDir": "manual"
+}
diff --git a/test/integration/package.json b/test/integration/package.json
index f4b97e4ca..afdfdc6e2 100644
--- a/test/integration/package.json
+++ b/test/integration/package.json
@@ -29,7 +29,9 @@
         "test:watch": "vitest",
         "start": "npm run server",
         "server": "tsx watch --clear-screen=false scripts/cli.ts server",
-        "client": "tsx scripts/cli.ts client"
+        "client": "tsx scripts/cli.ts client",
+        "test:integration:bun": "bun test test/server/bun.test.ts",
+        "test:integration:deno": "deno test --config deno.json --no-check --allow-net --allow-read --allow-env test/server/deno.test.ts"
     },
     "devDependencies": {
         "@modelcontextprotocol/core": "workspace:^",
diff --git a/test/integration/test/server/bun.test.ts b/test/integration/test/server/bun.test.ts
new file mode 100644
index 000000000..66f37f12d
--- /dev/null
+++ b/test/integration/test/server/bun.test.ts
@@ -0,0 +1,54 @@
+/**
+ * Bun integration test
+ *
+ * Verifies the MCP server and client packages work natively on Bun.
+ * Run with: bun test test/server/bun.test.ts
+ */
+
+import { describe, it, expect, beforeAll, afterAll } from 'bun:test';
+import { McpServer, WebStandardStreamableHTTPServerTransport } from '@modelcontextprotocol/server';
+import { Client, StreamableHTTPClientTransport } from '@modelcontextprotocol/client';
+import * as z from 'zod/v4';
+
+describe('MCP on Bun', () => {
+  let httpServer: ReturnType<typeof Bun.serve>;
+  let transport: WebStandardStreamableHTTPServerTransport;
+
+  beforeAll(async () => {
+    const mcpServer = new McpServer({ name: 'test-server', version: '1.0.0' });
+
+    mcpServer.registerTool('greet', {
+      description: 'Greet someone',
+      inputSchema: z.object({ name: z.string() }),
+    }, async ({ name }) => ({
+      content: [{ type: 'text' as const, text: `Hello, ${name}!` }],
+    }));
+
+    transport = new WebStandardStreamableHTTPServerTransport();
+    await mcpServer.connect(transport);
+
+    httpServer = Bun.serve({
+      port: 0,
+      fetch: (req) => transport.handleRequest(req),
+    });
+  });
+
+  afterAll(async () => {
+    await transport?.close();
+    httpServer?.stop();
+  });
+
+  it('should handle MCP tool calls', async () => {
+    const client = new Client({ name: 'test-client', version: '1.0.0' });
+    const clientTransport = new StreamableHTTPClientTransport(
+      new URL(`http://localhost:${httpServer.port}`)
+    );
+
+    await client.connect(clientTransport);
+
+    const result = await client.callTool({ name: 'greet', arguments: { name: 'Bun' } });
+    expect(result.content).toEqual([{ type: 'text', text: 'Hello, Bun!' }]);
+
+    await client.close();
+  });
+});
diff --git a/test/integration/test/server/deno.test.ts b/test/integration/test/server/deno.test.ts
new file mode 100644
index 000000000..5c1fd4a67
--- /dev/null
+++ b/test/integration/test/server/deno.test.ts
@@ -0,0 +1,50 @@
+/**
+ * Deno integration test
+ *
+ * Verifies the MCP server and client packages work natively on Deno.
+ * Run with: deno test --config deno.json --no-check --allow-net --allow-read --allow-env test/server/deno.test.ts
+ */
+
+import assert from 'node:assert/strict';
+import { McpServer, WebStandardStreamableHTTPServerTransport } from '@modelcontextprotocol/server';
+import { Client, StreamableHTTPClientTransport } from '@modelcontextprotocol/client';
+import * as z from 'zod/v4';
+
+Deno.test({
+  name: 'MCP tool calls work on Deno',
+  sanitizeOps: false,
+  sanitizeResources: false,
+  async fn() {
+    const mcpServer = new McpServer({ name: 'test-server', version: '1.0.0' });
+
+    mcpServer.registerTool('greet', {
+      description: 'Greet someone',
+      inputSchema: z.object({ name: z.string() }),
+    }, async ({ name }) => ({
+      content: [{ type: 'text' as const, text: `Hello, ${name}!` }],
+    }));
+
+    const transport = new WebStandardStreamableHTTPServerTransport();
+    await mcpServer.connect(transport);
+
+    const httpServer = Deno.serve({ port: 0 }, (req) => transport.handleRequest(req));
+    const port = httpServer.addr.port;
+
+    try {
+      const client = new Client({ name: 'test-client', version: '1.0.0' });
+      const clientTransport = new StreamableHTTPClientTransport(
+        new URL(`http://localhost:${port}`)
+      );
+
+      await client.connect(clientTransport);
+
+      const result = await client.callTool({ name: 'greet', arguments: { name: 'Deno' } });
+      assert.deepStrictEqual(result.content, [{ type: 'text', text: 'Hello, Deno!' }]);
+
+      await client.close();
+    } finally {
+      await transport.close();
+      await httpServer.shutdown();
+    }
+  },
+});
diff --git a/test/integration/tsconfig.json b/test/integration/tsconfig.json
index 353e6a708..5d68aa999 100644
--- a/test/integration/tsconfig.json
+++ b/test/integration/tsconfig.json
@@ -1,7 +1,7 @@
 {
     "extends": "@modelcontextprotocol/tsconfig",
     "include": ["./"],
-    "exclude": ["node_modules", "dist"],
+    "exclude": ["node_modules", "dist", "test/server/bun.test.ts", "test/server/deno.test.ts"],
     "compilerOptions": {
         "paths": {
             "*": ["./*"],
diff --git a/test/integration/vitest.config.js b/test/integration/vitest.config.js
index 38f030fdd..85a00a0e6 100644
--- a/test/integration/vitest.config.js
+++ b/test/integration/vitest.config.js
@@ -1,3 +1,8 @@
+import { defineConfig, mergeConfig } from 'vitest/config';
 import baseConfig from '../../common/vitest-config/vitest.config.js';
 
-export default baseConfig;
+export default mergeConfig(baseConfig, defineConfig({
+    test: {
+        exclude: ['**/dist/**', '**/bun.test.ts', '**/deno.test.ts'],
+    },
+}));

From 024d9cd9dfa397a5654d2d22dbe5c7721d0c7d5d Mon Sep 17 00:00:00 2001
From: Konstantin Konstantinov <konstantin@mach5technology.com>
Date: Sun, 1 Mar 2026 01:37:07 +0200
Subject: [PATCH 2/4] fix: resolve lint and formatting issues in integration
 tests

Fix import sorting, suppress bun:test unresolved import, and apply
Prettier formatting to integration test files.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 test/integration/deno.json                |  2 +-
 test/integration/test/server/bun.test.ts  | 75 ++++++++++++-----------
 test/integration/test/server/deno.test.ts | 75 ++++++++++++-----------
 test/integration/vitest.config.js         | 13 ++--
 4 files changed, 87 insertions(+), 78 deletions(-)

diff --git a/test/integration/deno.json b/test/integration/deno.json
index fde86a1ef..026959001 100644
--- a/test/integration/deno.json
+++ b/test/integration/deno.json
@@ -1,3 +1,3 @@
 {
-  "nodeModulesDir": "manual"
+    "nodeModulesDir": "manual"
 }
diff --git a/test/integration/test/server/bun.test.ts b/test/integration/test/server/bun.test.ts
index 66f37f12d..229145aa8 100644
--- a/test/integration/test/server/bun.test.ts
+++ b/test/integration/test/server/bun.test.ts
@@ -5,50 +5,53 @@
  * Run with: bun test test/server/bun.test.ts
  */
 
-import { describe, it, expect, beforeAll, afterAll } from 'bun:test';
-import { McpServer, WebStandardStreamableHTTPServerTransport } from '@modelcontextprotocol/server';
 import { Client, StreamableHTTPClientTransport } from '@modelcontextprotocol/client';
+import { McpServer, WebStandardStreamableHTTPServerTransport } from '@modelcontextprotocol/server';
+// eslint-disable-next-line import/no-unresolved
+import { afterAll, beforeAll, describe, expect, it } from 'bun:test';
 import * as z from 'zod/v4';
 
 describe('MCP on Bun', () => {
-  let httpServer: ReturnType<typeof Bun.serve>;
-  let transport: WebStandardStreamableHTTPServerTransport;
-
-  beforeAll(async () => {
-    const mcpServer = new McpServer({ name: 'test-server', version: '1.0.0' });
-
-    mcpServer.registerTool('greet', {
-      description: 'Greet someone',
-      inputSchema: z.object({ name: z.string() }),
-    }, async ({ name }) => ({
-      content: [{ type: 'text' as const, text: `Hello, ${name}!` }],
-    }));
-
-    transport = new WebStandardStreamableHTTPServerTransport();
-    await mcpServer.connect(transport);
-
-    httpServer = Bun.serve({
-      port: 0,
-      fetch: (req) => transport.handleRequest(req),
+    let httpServer: ReturnType<typeof Bun.serve>;
+    let transport: WebStandardStreamableHTTPServerTransport;
+
+    beforeAll(async () => {
+        const mcpServer = new McpServer({ name: 'test-server', version: '1.0.0' });
+
+        mcpServer.registerTool(
+            'greet',
+            {
+                description: 'Greet someone',
+                inputSchema: z.object({ name: z.string() })
+            },
+            async ({ name }) => ({
+                content: [{ type: 'text' as const, text: `Hello, ${name}!` }]
+            })
+        );
+
+        transport = new WebStandardStreamableHTTPServerTransport();
+        await mcpServer.connect(transport);
+
+        httpServer = Bun.serve({
+            port: 0,
+            fetch: req => transport.handleRequest(req)
+        });
     });
-  });
 
-  afterAll(async () => {
-    await transport?.close();
-    httpServer?.stop();
-  });
+    afterAll(async () => {
+        await transport?.close();
+        httpServer?.stop();
+    });
 
-  it('should handle MCP tool calls', async () => {
-    const client = new Client({ name: 'test-client', version: '1.0.0' });
-    const clientTransport = new StreamableHTTPClientTransport(
-      new URL(`http://localhost:${httpServer.port}`)
-    );
+    it('should handle MCP tool calls', async () => {
+        const client = new Client({ name: 'test-client', version: '1.0.0' });
+        const clientTransport = new StreamableHTTPClientTransport(new URL(`http://localhost:${httpServer.port}`));
 
-    await client.connect(clientTransport);
+        await client.connect(clientTransport);
 
-    const result = await client.callTool({ name: 'greet', arguments: { name: 'Bun' } });
-    expect(result.content).toEqual([{ type: 'text', text: 'Hello, Bun!' }]);
+        const result = await client.callTool({ name: 'greet', arguments: { name: 'Bun' } });
+        expect(result.content).toEqual([{ type: 'text', text: 'Hello, Bun!' }]);
 
-    await client.close();
-  });
+        await client.close();
+    });
 });
diff --git a/test/integration/test/server/deno.test.ts b/test/integration/test/server/deno.test.ts
index 5c1fd4a67..ea5cd425b 100644
--- a/test/integration/test/server/deno.test.ts
+++ b/test/integration/test/server/deno.test.ts
@@ -6,45 +6,48 @@
  */
 
 import assert from 'node:assert/strict';
-import { McpServer, WebStandardStreamableHTTPServerTransport } from '@modelcontextprotocol/server';
+
 import { Client, StreamableHTTPClientTransport } from '@modelcontextprotocol/client';
+import { McpServer, WebStandardStreamableHTTPServerTransport } from '@modelcontextprotocol/server';
 import * as z from 'zod/v4';
 
 Deno.test({
-  name: 'MCP tool calls work on Deno',
-  sanitizeOps: false,
-  sanitizeResources: false,
-  async fn() {
-    const mcpServer = new McpServer({ name: 'test-server', version: '1.0.0' });
-
-    mcpServer.registerTool('greet', {
-      description: 'Greet someone',
-      inputSchema: z.object({ name: z.string() }),
-    }, async ({ name }) => ({
-      content: [{ type: 'text' as const, text: `Hello, ${name}!` }],
-    }));
-
-    const transport = new WebStandardStreamableHTTPServerTransport();
-    await mcpServer.connect(transport);
-
-    const httpServer = Deno.serve({ port: 0 }, (req) => transport.handleRequest(req));
-    const port = httpServer.addr.port;
-
-    try {
-      const client = new Client({ name: 'test-client', version: '1.0.0' });
-      const clientTransport = new StreamableHTTPClientTransport(
-        new URL(`http://localhost:${port}`)
-      );
-
-      await client.connect(clientTransport);
-
-      const result = await client.callTool({ name: 'greet', arguments: { name: 'Deno' } });
-      assert.deepStrictEqual(result.content, [{ type: 'text', text: 'Hello, Deno!' }]);
-
-      await client.close();
-    } finally {
-      await transport.close();
-      await httpServer.shutdown();
+    name: 'MCP tool calls work on Deno',
+    sanitizeOps: false,
+    sanitizeResources: false,
+    async fn() {
+        const mcpServer = new McpServer({ name: 'test-server', version: '1.0.0' });
+
+        mcpServer.registerTool(
+            'greet',
+            {
+                description: 'Greet someone',
+                inputSchema: z.object({ name: z.string() })
+            },
+            async ({ name }) => ({
+                content: [{ type: 'text' as const, text: `Hello, ${name}!` }]
+            })
+        );
+
+        const transport = new WebStandardStreamableHTTPServerTransport();
+        await mcpServer.connect(transport);
+
+        const httpServer = Deno.serve({ port: 0 }, req => transport.handleRequest(req));
+        const port = httpServer.addr.port;
+
+        try {
+            const client = new Client({ name: 'test-client', version: '1.0.0' });
+            const clientTransport = new StreamableHTTPClientTransport(new URL(`http://localhost:${port}`));
+
+            await client.connect(clientTransport);
+
+            const result = await client.callTool({ name: 'greet', arguments: { name: 'Deno' } });
+            assert.deepStrictEqual(result.content, [{ type: 'text', text: 'Hello, Deno!' }]);
+
+            await client.close();
+        } finally {
+            await transport.close();
+            await httpServer.shutdown();
+        }
     }
-  },
 });
diff --git a/test/integration/vitest.config.js b/test/integration/vitest.config.js
index 85a00a0e6..5aad0051c 100644
--- a/test/integration/vitest.config.js
+++ b/test/integration/vitest.config.js
@@ -1,8 +1,11 @@
 import { defineConfig, mergeConfig } from 'vitest/config';
 import baseConfig from '../../common/vitest-config/vitest.config.js';
 
-export default mergeConfig(baseConfig, defineConfig({
-    test: {
-        exclude: ['**/dist/**', '**/bun.test.ts', '**/deno.test.ts'],
-    },
-}));
+export default mergeConfig(
+    baseConfig,
+    defineConfig({
+        test: {
+            exclude: ['**/dist/**', '**/bun.test.ts', '**/deno.test.ts']
+        }
+    })
+);

From 3a8a56cd9eba65d30d8b9f59487292eff880e05c Mon Sep 17 00:00:00 2001
From: Konstantin Konstantinov <konstantin@mach5technology.com>
Date: Sun, 1 Mar 2026 01:41:53 +0200
Subject: [PATCH 3/4] chore: remove unnecessary deno.json config

Deno v2.x auto-detects package.json and node_modules without needing
explicit nodeModulesDir configuration.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 test/integration/deno.json                | 3 ---
 test/integration/package.json             | 2 +-
 test/integration/test/server/deno.test.ts | 2 +-
 3 files changed, 2 insertions(+), 5 deletions(-)
 delete mode 100644 test/integration/deno.json

diff --git a/test/integration/deno.json b/test/integration/deno.json
deleted file mode 100644
index 026959001..000000000
--- a/test/integration/deno.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-    "nodeModulesDir": "manual"
-}
diff --git a/test/integration/package.json b/test/integration/package.json
index afdfdc6e2..da21238ed 100644
--- a/test/integration/package.json
+++ b/test/integration/package.json
@@ -31,7 +31,7 @@
         "server": "tsx watch --clear-screen=false scripts/cli.ts server",
         "client": "tsx scripts/cli.ts client",
         "test:integration:bun": "bun test test/server/bun.test.ts",
-        "test:integration:deno": "deno test --config deno.json --no-check --allow-net --allow-read --allow-env test/server/deno.test.ts"
+        "test:integration:deno": "deno test --no-check --allow-net --allow-read --allow-env test/server/deno.test.ts"
     },
     "devDependencies": {
         "@modelcontextprotocol/core": "workspace:^",
diff --git a/test/integration/test/server/deno.test.ts b/test/integration/test/server/deno.test.ts
index ea5cd425b..7d45f815c 100644
--- a/test/integration/test/server/deno.test.ts
+++ b/test/integration/test/server/deno.test.ts
@@ -2,7 +2,7 @@
  * Deno integration test
  *
  * Verifies the MCP server and client packages work natively on Deno.
- * Run with: deno test --config deno.json --no-check --allow-net --allow-read --allow-env test/server/deno.test.ts
+ * Run with: deno test --no-check --allow-net --allow-read --allow-env test/server/deno.test.ts
  */
 
 import assert from 'node:assert/strict';

From cc4397acfc41d64ad31227be535386f175b03a33 Mon Sep 17 00:00:00 2001
From: Konstantin Konstantinov <konstantin@mach5technology.com>
Date: Sun, 1 Mar 2026 01:48:43 +0200
Subject: [PATCH 4/4] docs: add Bun and Deno runtime support to README and
 quickstarts

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 README.md                 | 10 +++++++++-
 docs/client-quickstart.md |  5 ++++-
 docs/server-quickstart.md |  3 +++
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 21dbec6a6..f068ec915 100644
--- a/README.md
+++ b/README.md
@@ -25,7 +25,7 @@
 
 The Model Context Protocol (MCP) allows applications to provide context for LLMs in a standardized way, separating the concerns of providing context from the actual LLM interaction.
 
-This repository contains the TypeScript SDK implementation of the MCP specification and ships:
+This repository contains the TypeScript SDK implementation of the MCP specification. It runs on **Node.js**, **Bun**, and **Deno**, and ships:
 
 - MCP **server** libraries (tools/resources/prompts, Streamable HTTP, stdio, auth helpers)
 - MCP **client** libraries (transports, high-level helpers, OAuth helpers)
@@ -57,12 +57,20 @@ They are intentionally thin adapters: they should not introduce new MCP function
 
 ```bash
 npm install @modelcontextprotocol/server zod
+# or
+bun add @modelcontextprotocol/server zod
+# or
+deno add npm:@modelcontextprotocol/server npm:zod
 ```
 
 ### Client
 
 ```bash
 npm install @modelcontextprotocol/client zod
+# or
+bun add @modelcontextprotocol/client zod
+# or
+deno add npm:@modelcontextprotocol/client npm:zod
 ```
 
 ### Optional middleware packages
diff --git a/docs/client-quickstart.md b/docs/client-quickstart.md
index bd695c7bb..0669ab8a7 100644
--- a/docs/client-quickstart.md
+++ b/docs/client-quickstart.md
@@ -19,10 +19,13 @@ This quickstart assumes you have familiarity with:
 
 Before starting, ensure your system meets these requirements:
 
-- Node.js 20 or higher installed
+- Node.js 20 or higher installed (or **Bun** / **Deno** — the SDK supports all three runtimes)
 - Latest version of `npm` installed
 - An Anthropic API key from the [Anthropic Console](https://console.anthropic.com/settings/keys)
 
+> [!TIP]
+> This tutorial uses Node.js and npm, but you can substitute `bun` or `deno` commands where appropriate. For example, use `bun add` instead of `npm install`, or run the client with `bun run` / `deno run`.
+
 ## Set up your environment
 
 First, let's create and set up our project:
diff --git a/docs/server-quickstart.md b/docs/server-quickstart.md
index ffa49cec5..4ee04fd9c 100644
--- a/docs/server-quickstart.md
+++ b/docs/server-quickstart.md
@@ -36,6 +36,9 @@ node --version
 npm --version
 ```
 
+> [!TIP]
+> The MCP SDK also works with **Bun** and **Deno**. This tutorial uses Node.js, but you can substitute `bun` or `deno` commands where appropriate. For HTTP-based servers on Bun or Deno, use `WebStandardStreamableHTTPServerTransport` instead of the Node.js-specific transport — see the [server guide](./server.md) for details.
+
 ## Set up your environment
 
 First, let's install Node.js and npm if you haven't already. You can download them from [nodejs.org](https://nodejs.org/).