diff --git a/src/cli/commands/dev/browser-mode.ts b/src/cli/commands/dev/browser-mode.ts
index 77342e7f1..3489e0cc0 100644
--- a/src/cli/commands/dev/browser-mode.ts
+++ b/src/cli/commands/dev/browser-mode.ts
@@ -129,7 +129,9 @@ export async function launchBrowserDev(): Promise<void> {
     process.exit(1);
   }
 
-  await runCliDeploy();
+  if (hasHarnesses) {
+    await runCliDeploy();
+  }
 
   const configRoot = findConfigRoot(workingDir);
   const persistTracesDir = path.join(configRoot ?? workingDir, '.cli', 'traces');
diff --git a/src/cli/commands/dev/command.tsx b/src/cli/commands/dev/command.tsx
index d34dfa3e2..f588f3996 100644
--- a/src/cli/commands/dev/command.tsx
+++ b/src/cli/commands/dev/command.tsx
@@ -389,8 +389,8 @@ export const registerDev = (program: Command) => {
           // Get provider info from agent config
           const providerInfo = '(see agent code)';
 
-          // Deploy resources before starting dev server
-          if (!opts.skipDeploy) {
+          // Deploy resources before starting dev server (only when harnesses need it)
+          if (!opts.skipDeploy && hasHarnesses) {
             await runCliDeploy();
           }
 
diff --git a/src/cli/tui/hooks/useDevDeploy.ts b/src/cli/tui/hooks/useDevDeploy.ts
index e081a4eec..f815e8dbc 100644
--- a/src/cli/tui/hooks/useDevDeploy.ts
+++ b/src/cli/tui/hooks/useDevDeploy.ts
@@ -49,6 +49,19 @@ export function useDevDeploy({ skip, ready = true }: UseDevDeployOptions = {}):
       try {
         const configIO = new ConfigIO();
 
+        // Only deploy if the project has harnesses (cloud-dependent resources).
+        // Plain agents (Strands, LangGraph, etc.) run locally and don't need deployment.
+        try {
+          const projectSpec = await configIO.readProjectSpec();
+          const hasHarnesses = (projectSpec.harnesses ?? []).length > 0;
+          if (!hasHarnesses) {
+            onProgress('Local agent — no deploy needed', 'success');
+            return;
+          }
+        } catch {
+          // If we can't read project spec, proceed with deploy as a safe default
+        }
+
         // Auto-populate aws-targets.json if empty
         try {
           const targets = await configIO.readAWSDeploymentTargets();