feat: make MCP SDK a peer dependency (#168)

* feat: make MCP SDK a peer dependency

- Move @modelcontextprotocol/sdk from dependencies to peerDependencies (^1.20.0)
- Add to devDependencies for local development (^1.24.3)
- Externalize SDK from all build entry points (app, app-bridge, react, server)

Benefits:
- Consumers control their SDK version
- Deduplication when consumer already has SDK
- Follows pattern of react/zod peer deps

* fix: require SDK ^1.24.0 for Zod 4 compatibility

Earlier SDK versions have Zod type incompatibilities that cause build errors.

* chore: update examples to SDK ^1.24.0 to match peer dep

Author: ochafik

build.bun.ts

@@ -23,13 +23,20 @@ function buildJs(entrypoint: string, opts: Record<string, any> = {}) {
 }
 
 await Promise.all([
-  buildJs("src/app.ts", { outdir: "dist/src" }),
+  buildJs("src/app.ts", {
+    outdir: "dist/src",
+    external: ["@modelcontextprotocol/sdk"],
+  }),
   buildJs("src/app-bridge.ts", {
     outdir: "dist/src",
     external: ["@modelcontextprotocol/sdk"],
   }),
   buildJs("src/react/index.tsx", {
     outdir: "dist/src/react",
-    external: ["react", "react-dom"],
+    external: ["react", "react-dom", "@modelcontextprotocol/sdk"],
+  }),
+  buildJs("src/server/index.ts", {
+    outdir: "dist/src/server",
+    external: ["@modelcontextprotocol/sdk"],
   }),
 ]);

examples/basic-host/package.json

@@ -12,7 +12,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "react": "^19.2.0",
     "react-dom": "^19.2.0",
     "zod": "^4.1.13"

examples/basic-server-react/package.json

@@ -12,7 +12,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "react": "^19.2.0",
     "react-dom": "^19.2.0",
     "zod": "^4.1.13"

examples/basic-server-vanillajs/package.json

@@ -12,7 +12,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "zod": "^4.1.13"
   },
   "devDependencies": {

examples/budget-allocator-server/package.json

@@ -15,7 +15,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "chart.js": "^4.4.0",
     "zod": "^4.1.13"
   },

examples/cohort-heatmap-server/package.json

@@ -15,7 +15,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "react": "^19.2.0",
     "react-dom": "^19.2.0",
     "zod": "^4.1.13"

examples/customer-segmentation-server/package.json

@@ -15,7 +15,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "chart.js": "^4.4.0",
     "zod": "^4.1.13"
   },

examples/scenario-modeler-server/package.json

@@ -15,7 +15,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "chart.js": "^4.4.0",
     "react": "^19.2.0",
     "react-dom": "^19.2.0",

examples/system-monitor-server/package.json

@@ -15,7 +15,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "chart.js": "^4.4.0",
     "systeminformation": "^5.27.11",
     "zod": "^4.1.13"

examples/threejs-server/package.json

@@ -15,7 +15,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/ext-apps": "../..",
-    "@modelcontextprotocol/sdk": "^1.22.0",
+    "@modelcontextprotocol/sdk": "^1.24.0",
     "react": "^19.2.0",
     "react-dom": "^19.2.0",
     "three": "^0.181.0",