Implement MCP 2026-07-28 (#2286)

Co-authored-by: Matt <77928207+mattzcarey@users.noreply.github.com>
Co-authored-by: Konstantin Konstantinov <KKonstantinov@users.noreply.github.com>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

examples/standalone-get/client.ts

@@ -0,0 +1,40 @@
+/**
+ * Connects (2025-era), opens the standalone GET stream by registering a
+ * `listChanged` handler, calls `add_resource` to trigger a
+ * `notifications/resources/list_changed` over that stream, and asserts it
+ * arrived.
+ */
+import { check, parseExampleArgs } from '@mcp-examples/shared';
+import { Client, StreamableHTTPClientTransport } from '@modelcontextprotocol/client';
+
+const { url } = parseExampleArgs();
+
+let received = 0;
+const client = new Client(
+    { name: 'standalone-get-client', version: '1.0.0' },
+    {
+        // Explicitly the 2025 `initialize` handshake — the standalone GET
+        // stream is a sessionful-2025 transport feature, so this story is
+        // legacy-only by design (was reaching 2025 by fallback; pin it).
+        versionNegotiation: { mode: 'legacy' },
+        listChanged: { resources: { autoRefresh: false, debounceMs: 0, onChanged: () => void received++ } }
+    }
+);
+await client.connect(new StreamableHTTPClientTransport(new URL(url)));
+
+const before = await client.listResources();
+check.ok(before.resources.length > 0);
+
+// Mutate on demand → server emits list_changed over the standalone GET stream.
+await client.callTool({ name: 'add_resource', arguments: { content: 'hello' } });
+const deadline = Date.now() + 5000;
+while (received < 1) {
+    if (Date.now() > deadline) throw new Error('no listChanged within 5s');
+    await new Promise(r => setTimeout(r, 25));
+}
+check.ok(received >= 1);
+
+const after = await client.listResources();
+check.ok(after.resources.length > before.resources.length);
+
+await client.close();