CRITICAL BUGFIX (daemon,app): Session spawning via tmux always fails — PID mismatch timeout, hidden errors, orphaned windows (#272)

.github/workflows/cli-smoke-test.yml

@@ -92,8 +92,14 @@ jobs:
         cache-dependency-path: yarn.lock
 
     - name: Install dependencies
+      env:
+        SKIP_HAPPY_WIRE_BUILD: "1"
       run: yarn install --immutable
 
+    - name: Build happy-wire
+      shell: bash
+      run: cd packages/happy-wire && yarn build
+
     - name: Build package
       run: yarn workspace happy-coder build
 

packages/happy-app/sources/app/(app)/new/index.tsx

@@ -1061,17 +1061,21 @@ function NewSessionWizard() {
                         return 'session'
                     },
                 });
+            } else if (result.type === 'error') {
+                throw new Error(result.errorMessage);
             } else {
-                throw new Error('Session spawning failed - no session ID returned.');
+                throw new Error('Session spawning failed - unexpected response.');
             }
         } catch (error) {
             console.error('Failed to start session', error);
             let errorMessage = 'Failed to start session. Make sure the daemon is running on the target machine.';
-            if (error instanceof Error) {
+            if (error instanceof Error && error.message) {
                 if (error.message.includes('timeout')) {
                     errorMessage = 'Session startup timed out. The machine may be slow or the daemon may not be responding.';
                 } else if (error.message.includes('Socket not connected')) {
                     errorMessage = 'Not connected to server. Check your internet connection.';
+                } else {
+                    errorMessage = error.message;
                 }
             }
             Modal.alert(t('common.error'), errorMessage);

packages/happy-cli/package.json

@@ -57,7 +57,7 @@
   "scripts": {
     "why do we need to build before running tests / dev?": "We need the binary to be built so we run daemon commands which directly run the binary - we don't want them to go out of sync or have custom spawn logic depending how we started happy",
     "typecheck": "tsc --noEmit",
-    "build": "shx rm -rf dist && npx tsc --noEmit && pkgroll",
+    "build": "shx rm -rf dist && tsc --noEmit && pkgroll",
     "test": "$npm_execpath run build && vitest run",
     "start": "$npm_execpath run build && node ./bin/happy.mjs",
     "cli": "tsx src/index.ts",

packages/happy-cli/src/agent/acp/runAcp.ts

@@ -745,7 +745,7 @@ export async function runAcp(opts: {
         if (verbose) {
           logAcp('muted', `Outgoing modes from ${opts.agentName} (${modes.availableModes.length}), current=${modes.currentModeId}:`);
           for (const mode of modes.availableModes) {
-            logAcp('muted', `  mode=${mode.id} name=${mode.name}${formatOptionalDetail(mode.description, 160)}`);
+            logAcp('muted', `  mode=${mode.id} name=${mode.name}${formatOptionalDetail(mode.description ?? undefined, 160)}`);
           }
         }
         session.updateMetadata((currentMetadata) =>

packages/happy-cli/src/api/types.ts

@@ -261,6 +261,7 @@ export type Metadata = {
   happyToolsDir: string,
   startedFromDaemon?: boolean,
   hostPid?: number,
+  spawnToken?: string,
   startedBy?: 'daemon' | 'terminal',
   // Lifecycle state management
   lifecycleState?: 'running' | 'archiveRequested' | 'archived' | string,

packages/happy-cli/src/claude/runClaude.ts

@@ -108,6 +108,7 @@ export async function runClaude(credentials: Credentials, options: StartOptions
         happyToolsDir: resolve(projectPath(), 'tools', 'unpacked'),
         startedFromDaemon: options.startedBy === 'daemon',
         hostPid: process.pid,
+        spawnToken: process.env.HAPPY_SPAWN_TOKEN || undefined,
         startedBy: options.startedBy || 'terminal',
         // Initialize lifecycle state
         lifecycleState: 'running',

packages/happy-cli/src/utils/createSessionMetadata.test.ts

@@ -1,4 +1,4 @@
-import { describe, expect, it } from 'vitest';
+import { describe, expect, it, beforeEach, afterEach } from 'vitest';
 import type { SandboxConfig } from '@/persistence';
 import { createSessionMetadata } from './createSessionMetadata';
 
@@ -71,4 +71,47 @@ describe('createSessionMetadata', () => {
 
         expect(metadata.dangerouslySkipPermissions).toBe(true);
     });
+
+    describe('spawnToken', () => {
+        const originalSpawnToken = process.env.HAPPY_SPAWN_TOKEN;
+
+        afterEach(() => {
+            if (originalSpawnToken !== undefined) {
+                process.env.HAPPY_SPAWN_TOKEN = originalSpawnToken;
+            } else {
+                delete process.env.HAPPY_SPAWN_TOKEN;
+            }
+        });
+
+        it('sets metadata.spawnToken from HAPPY_SPAWN_TOKEN env var', () => {
+            process.env.HAPPY_SPAWN_TOKEN = 'abc123';
+            const { metadata } = createSessionMetadata({
+                flavor: 'claude',
+                machineId: 'machine-6',
+            });
+
+            expect(metadata.spawnToken).toBe('abc123');
+        });
+
+        it('sets metadata.spawnToken to undefined when env var not set', () => {
+            delete process.env.HAPPY_SPAWN_TOKEN;
+            const { metadata } = createSessionMetadata({
+                flavor: 'claude',
+                machineId: 'machine-7',
+            });
+
+            expect(metadata.spawnToken).toBeUndefined();
+        });
+
+        it('sets metadata.spawnToken to undefined when env var is empty string', () => {
+            process.env.HAPPY_SPAWN_TOKEN = '';
+            const { metadata } = createSessionMetadata({
+                flavor: 'claude',
+                machineId: 'machine-8',
+            });
+
+            // '' || undefined → undefined
+            expect(metadata.spawnToken).toBeUndefined();
+        });
+    });
 });

packages/happy-cli/src/utils/createSessionMetadata.ts

@@ -84,6 +84,7 @@ export function createSessionMetadata(opts: CreateSessionMetadataOptions): Sessi
         happyToolsDir: resolve(projectPath(), 'tools', 'unpacked'),
         startedFromDaemon: opts.startedBy === 'daemon',
         hostPid: process.pid,
+        spawnToken: process.env.HAPPY_SPAWN_TOKEN || undefined,
         startedBy: opts.startedBy || 'terminal',
         lifecycleState: 'running',
         lifecycleStateSince: Date.now(),