diff --git a/src/cli/doctor.ts b/src/cli/doctor.ts
index 27ad23b..4cc9d8c 100644
--- a/src/cli/doctor.ts
+++ b/src/cli/doctor.ts
@@ -1,8 +1,53 @@
-import { spawnSync, type SpawnSyncReturns } from 'child_process';
+import { spawn, spawnSync, type SpawnSyncReturns } from 'child_process';
 import { existsSync } from 'fs';
 import { join } from 'path';
 import { serviceManager, type ServiceStatus } from '../env/service-manager.js';
 
+/**
+ * Promisified spawn wrapper that collects stdout/stderr and resolves with status code.
+ * Note: This function always resolves (never rejects) to match spawnSync behavior.
+ * Errors are communicated via status code and stderr, not via Promise rejection.
+ */
+function spawnAsync(
+  command: string,
+  args: string[],
+  options: { cwd: string; encoding: BufferEncoding }
+): Promise<Pick<SpawnSyncReturns<string>, 'status' | 'stdout' | 'stderr'>> {
+  return new Promise((resolve) => {
+    const child = spawn(command, args, {
+      cwd: options.cwd,
+      stdio: ['ignore', 'pipe', 'pipe']
+    });
+
+    let stdout = '';
+    let stderr = '';
+
+    child.stdout?.on('data', (data) => {
+      stdout += data.toString(options.encoding);
+    });
+
+    child.stderr?.on('data', (data) => {
+      stderr += data.toString(options.encoding);
+    });
+
+    child.on('close', (code) => {
+      resolve({
+        status: code ?? 0,
+        stdout,
+        stderr
+      });
+    });
+
+    child.on('error', (error) => {
+      resolve({
+        status: 1,
+        stdout,
+        stderr: stderr || error.message
+      });
+    });
+  });
+}
+
 export const DEFAULT_MCP_PROFILES = [
   'mcp-filesystem',
   'mcp-playwright',
@@ -41,7 +86,7 @@ export interface DoctorDependencies {
     command: string,
     args: string[],
     options: { cwd: string; encoding: BufferEncoding }
-  ) => Pick<SpawnSyncReturns<string>, 'status' | 'stdout' | 'stderr'>;
+  ) => Promise<Pick<SpawnSyncReturns<string>, 'status' | 'stdout' | 'stderr'>>;
   getServiceStatus?: (name: string) => Promise<ServiceStatus>;
   getCodexRegistration?: (name: string) => { codexName: string; url: string } | null;
 }
@@ -128,8 +173,7 @@ export async function runDoctor(options: DoctorOptions = {}, deps: DoctorDepende
   const cwd = options.cwd ?? process.cwd();
   const profileNames = parseProfileList(options.mcpProfiles);
   const fileExists = deps.fileExists ?? existsSync;
-  const spawnCommand = deps.spawnCommand
-    ?? ((command, args, spawnOptions) => spawnSync(command, args, spawnOptions));
+  const spawnCommand = deps.spawnCommand ?? spawnAsync;
   const getServiceStatus = deps.getServiceStatus ?? ((name: string) => serviceManager.status(name));
   const getCodexRegistration = deps.getCodexRegistration
     ?? ((name: string) => serviceManager.codexRegistration(name));
@@ -146,7 +190,7 @@ export async function runDoctor(options: DoctorOptions = {}, deps: DoctorDepende
   });
 
   if (distExists) {
-    const cliHelp = spawnCommand('node', [distCliPath, '--help'], {
+    const cliHelp = await spawnCommand('node', [distCliPath, '--help'], {
       cwd,
       encoding: 'utf8'
     });
@@ -164,7 +208,7 @@ export async function runDoctor(options: DoctorOptions = {}, deps: DoctorDepende
   }
 
   if (!options.skipCodexAuth) {
-    const loginStatus = spawnCommand('codex', ['login', 'status'], {
+    const loginStatus = await spawnCommand('codex', ['login', 'status'], {
       cwd,
       encoding: 'utf8'
     });
@@ -180,7 +224,7 @@ export async function runDoctor(options: DoctorOptions = {}, deps: DoctorDepende
     });
   }
 
-  const codexMcpList = spawnCommand('codex', ['mcp', 'list', '--json'], {
+  const codexMcpList = await spawnCommand('codex', ['mcp', 'list', '--json'], {
     cwd,
     encoding: 'utf8'
   });
diff --git a/src/cli/launch.ts b/src/cli/launch.ts
index 71e4892..72935f2 100644
--- a/src/cli/launch.ts
+++ b/src/cli/launch.ts
@@ -1,4 +1,4 @@
-import { spawnSync, type SpawnSyncReturns } from 'child_process';
+import { spawn, spawnSync, type SpawnSyncReturns } from 'child_process';
 import { existsSync } from 'fs';
 import { join } from 'path';
 import {
@@ -17,6 +17,51 @@ import {
 } from './doctor.js';
 import { BridgeError, ErrorCode } from '../core/errors.js';
 
+/**
+ * Promisified spawn wrapper that collects stdout/stderr and resolves with status code.
+ * Note: This function always resolves (never rejects) to match spawnSync behavior.
+ * Errors are communicated via status code and stderr, not via Promise rejection.
+ */
+function spawnAsync(
+  command: string,
+  args: string[],
+  options: { cwd: string; encoding: BufferEncoding }
+): Promise<Pick<SpawnSyncReturns<string>, 'status' | 'stdout' | 'stderr'>> {
+  return new Promise((resolve) => {
+    const child = spawn(command, args, {
+      cwd: options.cwd,
+      stdio: ['ignore', 'pipe', 'pipe']
+    });
+
+    let stdout = '';
+    let stderr = '';
+
+    child.stdout?.on('data', (data) => {
+      stdout += data.toString(options.encoding);
+    });
+
+    child.stderr?.on('data', (data) => {
+      stderr += data.toString(options.encoding);
+    });
+
+    child.on('close', (code) => {
+      resolve({
+        status: code ?? 0,
+        stdout,
+        stderr
+      });
+    });
+
+    child.on('error', (error) => {
+      resolve({
+        status: 1,
+        stdout,
+        stderr: stderr || error.message
+      });
+    });
+  });
+}
+
 export interface LaunchStep {
   id: string;
   ok: boolean;
@@ -62,9 +107,8 @@ function normalizeSpawn(
     command: string,
     args: string[],
     options: { cwd: string; encoding: BufferEncoding }
-  ) => Pick<SpawnSyncReturns<string>, 'status' | 'stdout' | 'stderr'> {
-  return deps.spawnCommand
-    ?? ((command, args, spawnOptions) => spawnSync(command, args, spawnOptions));
+  ) => Promise<Pick<SpawnSyncReturns<string>, 'status' | 'stdout' | 'stderr'>> {
+  return deps.spawnCommand ?? spawnAsync;
 }
 
 function buildLaunchReport(steps: LaunchStep[], doctorReport: DoctorReport): LaunchReport {
@@ -148,8 +192,8 @@ export async function runLaunch(options: LaunchOptions = {}, deps: LaunchDepende
   const distExists = fileExists(distCliPath);
 
   const preflightStep: LaunchStep = distExists
-    ? (() => {
-      const cliHelp = spawnCommand('node', [distCliPath, '--help'], {
+    ? await (async () => {
+      const cliHelp = await spawnCommand('node', [distCliPath, '--help'], {
         cwd,
         encoding: 'utf8'
       });
@@ -185,8 +229,8 @@ export async function runLaunch(options: LaunchOptions = {}, deps: LaunchDepende
       ok: true,
       details: 'Skipped codex auth check (--skip-codex-auth).'
     }
-    : (() => {
-      const loginStatus = spawnCommand('codex', ['login', 'status'], {
+    : await (async () => {
+      const loginStatus = await spawnCommand('codex', ['login', 'status'], {
         cwd,
         encoding: 'utf8'
       });
@@ -295,7 +339,7 @@ export async function runLaunch(options: LaunchOptions = {}, deps: LaunchDepende
           continue;
         }
 
-        const remove = spawnCommand('codex', ['mcp', 'remove', registration.codexName], {
+        const remove = await spawnCommand('codex', ['mcp', 'remove', registration.codexName], {
           cwd,
           encoding: 'utf8'
         });
@@ -307,7 +351,7 @@ export async function runLaunch(options: LaunchOptions = {}, deps: LaunchDepende
           );
         }
 
-        const add = spawnCommand('codex', ['mcp', 'add', registration.codexName, '--url', registration.url], {
+        const add = await spawnCommand('codex', ['mcp', 'add', registration.codexName, '--url', registration.url], {
           cwd,
           encoding: 'utf8'
         });
diff --git a/tests/cli/doctor.test.ts b/tests/cli/doctor.test.ts
index 2ac04d7..fe86ca8 100644
--- a/tests/cli/doctor.test.ts
+++ b/tests/cli/doctor.test.ts
@@ -18,7 +18,7 @@ describe('runDoctor', () => {
   it('fails when the dist CLI artifact is missing', async () => {
     const deps: DoctorDependencies = {
       fileExists: () => false,
-      spawnCommand: (command, args) => {
+      spawnCommand: async (command, args) => {
         if (command === 'codex' && args.join(' ') === 'mcp list --json') {
           return {
             status: 0,
@@ -49,7 +49,7 @@ describe('runDoctor', () => {
   it('fails codex auth check when codex login status returns non-zero', async () => {
     const deps: DoctorDependencies = {
       fileExists: () => true,
-      spawnCommand: (command, args) => {
+      spawnCommand: async (command, args) => {
         if (command === 'node' && args.includes('--help')) {
           return { status: 0, stdout: 'ok', stderr: '' };
         }
@@ -95,7 +95,7 @@ describe('runDoctor', () => {
 
     const deps: DoctorDependencies = {
       fileExists: () => true,
-      spawnCommand: (command, args) => {
+      spawnCommand: async (command, args) => {
         if (command === 'node' && args.includes('--help')) {
           return { status: 0, stdout: 'ok', stderr: '' };
         }
@@ -139,7 +139,7 @@ describe('runDoctor', () => {
   it('returns actionable remediation for failing MCP profile checks', async () => {
     const deps: DoctorDependencies = {
       fileExists: () => true,
-      spawnCommand: (command, args) => {
+      spawnCommand: async (command, args) => {
         if (command === 'node' && args.includes('--help')) {
           return { status: 0, stdout: 'ok', stderr: '' };
         }
@@ -176,7 +176,7 @@ describe('runDoctor', () => {
   it('fails codex MCP parsing checks when codex mcp list returns malformed JSON', async () => {
     const deps: DoctorDependencies = {
       fileExists: () => true,
-      spawnCommand: (command, args) => {
+      spawnCommand: async (command, args) => {
         if (command === 'node' && args.includes('--help')) {
           return { status: 0, stdout: 'ok', stderr: '' };
         }
diff --git a/tests/cli/launch.test.ts b/tests/cli/launch.test.ts
index 6ee818a..cbd2320 100644
--- a/tests/cli/launch.test.ts
+++ b/tests/cli/launch.test.ts
@@ -15,7 +15,7 @@ describe('runLaunch', () => {
 
     const deps: LaunchDependencies = {
       fileExists: () => true,
-      spawnCommand: (command, args) => {
+      spawnCommand: async (command, args) => {
         spawnCalls.push(`${command} ${args.join(' ')}`);
 
         if (command === 'node' && args.includes('--help')) {
@@ -113,7 +113,7 @@ describe('runLaunch', () => {
       },
       {
         fileExists: () => true,
-        spawnCommand: (command, args) => {
+        spawnCommand: async (command, args) => {
           if (command === 'node' && args.includes('--help')) {
             return { status: 0, stdout: 'ok', stderr: '' };
           }
@@ -147,7 +147,7 @@ describe('runLaunch', () => {
       },
       {
         fileExists: () => true,
-        spawnCommand: (command, args) => {
+        spawnCommand: async (command, args) => {
           if (command === 'node' && args.includes('--help')) {
             return { status: 0, stdout: 'ok', stderr: '' };
           }