diff --git a/extension/src/editor/AspireCodeLensProvider.ts b/extension/src/editor/AspireCodeLensProvider.ts
index fea20d62065..1efd5be2142 100644
--- a/extension/src/editor/AspireCodeLensProvider.ts
+++ b/extension/src/editor/AspireCodeLensProvider.ts
@@ -27,6 +27,7 @@ import {
     codeLensViewLogs,
     codeLensCommand,
 } from '../loc/strings';
+import { isNotNullOrUndefined } from '../utils/typeGuards';
 
 export class AspireCodeLensProvider implements vscode.CodeLensProvider {
     private readonly _onDidChangeCodeLenses = new vscode.EventEmitter<void>();
@@ -200,6 +201,8 @@ export class AspireCodeLensProvider implements vscode.CodeLensProvider {
 }
 
 export function getCodeLensStateLabel(state: string, stateStyle: string, exitCode?: number | null): string {
+    const nonZeroExitCode = isNotNullOrUndefined(exitCode) && exitCode !== 0 ? exitCode : undefined;
+
     switch (state) {
         case ResourceState.Running:
         case ResourceState.Active:
@@ -226,9 +229,9 @@ export function getCodeLensStateLabel(state: string, stateStyle: string, exitCod
         case ResourceState.Exited:
         case ResourceState.Stopped:
             if (stateStyle === StateStyle.Error) {
-                return exitCode != null && exitCode !== 0 ? codeLensResourceStoppedErrorWithExitCode(exitCode) : codeLensResourceStoppedError;
+                return nonZeroExitCode !== undefined ? codeLensResourceStoppedErrorWithExitCode(nonZeroExitCode) : codeLensResourceStoppedError;
             }
-            return exitCode != null && exitCode !== 0 ? codeLensResourceStoppedWithExitCode(exitCode) : codeLensResourceStopped;
+            return nonZeroExitCode !== undefined ? codeLensResourceStoppedWithExitCode(nonZeroExitCode) : codeLensResourceStopped;
         default:
             return state || codeLensResourceStopped;
     }
diff --git a/extension/src/editor/AspireGutterDecorationProvider.ts b/extension/src/editor/AspireGutterDecorationProvider.ts
index 15461949d04..2bc88a7a34d 100644
--- a/extension/src/editor/AspireGutterDecorationProvider.ts
+++ b/extension/src/editor/AspireGutterDecorationProvider.ts
@@ -6,6 +6,7 @@ import './parsers/jsTsAppHostParser';
 import { AspireAppHostTreeProvider } from '../views/AspireAppHostTreeProvider';
 import { findResourceState, findWorkspaceResourceState } from './resourceStateUtils';
 import { ResourceState, StateStyle, HealthStatus } from './resourceConstants';
+import { isNotNullOrUndefined } from '../utils/typeGuards';
 
 type GutterCategory = 'running' | 'warning' | 'error' | 'starting' | 'stopped' | 'completed';
 
@@ -90,7 +91,7 @@ function classifyState(state: string, stateStyle: string, healthStatus: string,
         case ResourceState.Finished:
         case ResourceState.Exited:
         case ResourceState.Stopped:
-            if (stateStyle === StateStyle.Error || (exitCode != null && exitCode !== 0)) {
+            if (stateStyle === StateStyle.Error || (isNotNullOrUndefined(exitCode) && exitCode !== 0)) {
                 return 'error';
             }
             return 'completed';
diff --git a/extension/src/utils/typeGuards.ts b/extension/src/utils/typeGuards.ts
new file mode 100644
index 00000000000..cf6451367da
--- /dev/null
+++ b/extension/src/utils/typeGuards.ts
@@ -0,0 +1,3 @@
+export function isNotNullOrUndefined<T>(value: T | null | undefined): value is T {
+    return value !== null && value !== undefined;
+}
diff --git a/extension/src/views/AspireAppHostTreeProvider.ts b/extension/src/views/AspireAppHostTreeProvider.ts
index f9c314675db..1ba6b4b3ef6 100644
--- a/extension/src/views/AspireAppHostTreeProvider.ts
+++ b/extension/src/views/AspireAppHostTreeProvider.ts
@@ -32,6 +32,7 @@ import {
     ViewMode,
     shortenPath,
 } from './AppHostDataRepository';
+import { isNotNullOrUndefined } from '../utils/typeGuards';
 
 type TreeElement = AppHostItem | PidItem | EndpointUrlItem | ResourcesGroupItem | ResourceItem | WorkspaceResourcesItem | HealthChecksGroupItem | HealthCheckItem;
 
@@ -194,6 +195,7 @@ export function getResourceContextValue(resource: ResourceJson): string {
 export function getResourceIcon(resource: ResourceJson): vscode.ThemeIcon {
     const state = resource.state;
     const health = resource.healthStatus;
+    const hasNonZeroExitCode = isNotNullOrUndefined(resource.exitCode) && resource.exitCode !== 0;
     switch (state) {
         case ResourceState.Running:
         case ResourceState.Active:
@@ -210,7 +212,7 @@ export function getResourceIcon(resource: ResourceJson): vscode.ThemeIcon {
         case ResourceState.Finished:
         case ResourceState.Exited:
         case ResourceState.Stopped:
-            if (resource.stateStyle === StateStyle.Error || (resource.exitCode != null && resource.exitCode !== 0)) {
+            if (resource.stateStyle === StateStyle.Error || hasNonZeroExitCode) {
                 return new vscode.ThemeIcon('error', new vscode.ThemeColor('list.errorForeground'));
             }
             return new vscode.ThemeIcon('pass', new vscode.ThemeColor('charts.green'));
@@ -225,7 +227,7 @@ export function getResourceIcon(resource: ResourceJson): vscode.ThemeIcon {
         case ResourceState.NotStarted:
             return new vscode.ThemeIcon('record', new vscode.ThemeColor('descriptionForeground'));
         default:
-            if (state === null || state === undefined) {
+            if (!isNotNullOrUndefined(state)) {
                 return new vscode.ThemeIcon('record', new vscode.ThemeColor('descriptionForeground'));
             }
             return new vscode.ThemeIcon('circle-filled', new vscode.ThemeColor('aspire.brandPurple'));
@@ -273,7 +275,7 @@ export function buildResourceDescription(resource: ResourceJson): string {
         const passed = Object.values(reports).filter(r => r.status === 'Healthy').length;
         parts.push(resourceDescriptionHealth(passed, total));
     }
-    if (exitCode != null && exitCode !== 0) {
+    if (isNotNullOrUndefined(exitCode) && exitCode !== 0) {
         parts.push(resourceDescriptionExitCode(exitCode));
     }
     return parts.join(' · ');