fix(map-server): fix Express listen callback + add e2e tests

- Fix incorrect Express listen() callback signature (err param doesn't exist)
- Add map-server to e2e test suite with SLOW_SERVERS timeout (5s for tiles)
- Improve comment about experimental ui/update-model-context API

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: ochafik

examples/map-server/server-utils.ts

@@ -54,11 +54,7 @@ export async function startServer(
     }
   });
 
-  const httpServer = app.listen(port, (err) => {
-    if (err) {
-      console.error("Failed to start server:", err);
-      process.exit(1);
-    }
+  const httpServer = app.listen(port, () => {
     console.log(`${name} listening on http://localhost:${port}/mcp`);
   });
 

examples/map-server/src/mcp-app.ts

@@ -294,8 +294,10 @@ function scheduleLocationUpdate(cesiumViewer: any): void {
 
       log.info("Updating model context:", contextText);
 
-      // Warning: This request method isn't standard yet
+      // EXPERIMENTAL: This request method isn't standard yet and may change.
+      // It updates the model's context with the current map location.
       // See https://github.com/modelcontextprotocol/ext-apps/pull/125
+      // If the host doesn't support this, the request will silently fail.
       app.request(
         <any>{
           method: "ui/update-model-context",

tests/e2e/servers.spec.ts

@@ -13,6 +13,7 @@ const DYNAMIC_MASKS: Record<string, string[]> = {
   "basic-vue": ["#server-time"], // Server time display
   "cohort-heatmap": ['[class*="heatmapWrapper"]'], // Heatmap grid (random data)
   "customer-segmentation": [".chart-container"], // Scatter plot (random data)
+  // Note: map-server uses SLOW_SERVERS timeout instead of masking to wait for tiles
   "system-monitor": [
     ".chart-container", // CPU chart (highly dynamic)
     "#status-text", // Current timestamp
@@ -25,6 +26,12 @@ const DYNAMIC_MASKS: Record<string, string[]> = {
   "wiki-explorer": ["#graph"], // Force-directed graph (dynamic layout)
 };
 
+// Servers that need extra stabilization time (e.g., for tile loading, WebGL init)
+const SLOW_SERVERS: Record<string, number> = {
+  "map-server": 5000, // CesiumJS needs time for tiles to load
+  threejs: 2000, // Three.js WebGL initialization
+};
+
 // Server configurations (key is used for screenshot filenames, name is the MCP server name)
 const SERVERS = [
   { key: "integration", name: "Integration Test Server" },
@@ -37,6 +44,7 @@ const SERVERS = [
   { key: "budget-allocator", name: "Budget Allocator Server" },
   { key: "cohort-heatmap", name: "Cohort Heatmap Server" },
   { key: "customer-segmentation", name: "Customer Segmentation Server" },
+  { key: "map-server", name: "CesiumJS Map Server" },
   { key: "scenario-modeler", name: "SaaS Scenario Modeler" },
   { key: "sheet-music", name: "Sheet Music Server" },
   { key: "system-monitor", name: "System Monitor Server" },
@@ -121,7 +129,10 @@ SERVERS.forEach((server) => {
 
     test("screenshot matches golden", async ({ page }) => {
       await loadServer(page, server.name);
-      await page.waitForTimeout(500); // Brief stabilization
+
+      // Some servers (WebGL, tile-based) need extra stabilization time
+      const stabilizationMs = SLOW_SERVERS[server.key] ?? 500;
+      await page.waitForTimeout(stabilizationMs);
 
       // Get mask locators for dynamic content (timestamps, charts, etc.)
       const mask = getMaskLocators(page, server.key);