diff --git a/packages/cli/package.json b/packages/cli/package.json
index 377be96..2129f6b 100644
--- a/packages/cli/package.json
+++ b/packages/cli/package.json
@@ -34,6 +34,7 @@
     "chalk": "^5.3.0",
     "chokidar": "^4.0.0",
     "commander": "^12.0.0",
+    "execa": "^9.5.0",
     "fs-extra": "^11.2.0",
     "glob": "^11.0.0",
     "ora": "^8.1.0",
diff --git a/packages/cli/src/commands/build.ts b/packages/cli/src/commands/build.ts
index 8586b25..45034e0 100644
--- a/packages/cli/src/commands/build.ts
+++ b/packages/cli/src/commands/build.ts
@@ -4,7 +4,7 @@
  * Builds UI components and compiles TypeScript for production deployment.
  * Does NOT start the server - use 'leanmcp start' or 'node dist/main.js' after building.
  */
-import { spawn } from 'child_process';
+import { execa } from 'execa';
 import ora from 'ora';
 import path from 'path';
 import fs from 'fs-extra';
@@ -12,6 +12,23 @@ import { logger } from '../logger';
 import { scanUIApp, buildUIComponent, writeUIManifest } from '../vite';
 import { generateSchemaMetadata } from '../schema-extractor';
 
+/**
+ * Run TypeScript compiler with reliable cross-platform output capture
+ */
+async function runTypeScriptCompiler(cwd: string): Promise<void> {
+  try {
+    await execa('npx', ['tsc'], {
+      cwd,
+      preferLocal: true,
+      all: true, // Combine stdout + stderr into error.all
+    });
+  } catch (error: any) {
+    // execa includes full output in error.all
+    const output = error.all || error.stdout || error.stderr || error.message;
+    throw new Error(output || `tsc exited with code ${error.exitCode}`);
+  }
+}
+
 export async function buildCommand() {
   const cwd = process.cwd();
 
@@ -79,37 +96,24 @@ export async function buildCommand() {
   const tscSpinner = ora('Compiling TypeScript...').start();
 
   try {
-    await new Promise<void>((resolve, reject) => {
-      const tsc = spawn('npx', ['tsc'], {
-        cwd,
-        stdio: 'pipe',
-        shell: true,
-      });
-
-      let stdout = '';
-      let stderr = '';
-
-      tsc.stdout?.on('data', (data) => {
-        stdout += data;
-      });
-
-      tsc.stderr?.on('data', (data) => {
-        stderr += data;
-      });
-
-      tsc.on('close', (code) => {
-        if (code === 0) resolve();
-        // TypeScript outputs compilation errors to stdout, not stderr
-        else reject(new Error(stdout || stderr || `tsc exited with code ${code}`));
-      });
-
-      tsc.on('error', reject);
-    });
-
+    await runTypeScriptCompiler(cwd);
     tscSpinner.succeed('TypeScript compiled');
   } catch (error) {
     tscSpinner.fail('TypeScript compilation failed');
-    logger.error(error instanceof Error ? error.message : String(error));
+
+    // Display the full error output with proper formatting
+    const errorMessage = error instanceof Error ? error.message : String(error);
+
+    // Log each line for proper formatting
+    const lines = errorMessage.split('\n');
+    for (const line of lines) {
+      if (line.includes('error TS')) {
+        logger.error(line);
+      } else if (line.trim()) {
+        logger.log(line);
+      }
+    }
+
     process.exit(1);
   }
 
diff --git a/packages/cli/src/commands/deploy.ts b/packages/cli/src/commands/deploy.ts
index 4bb9f46..35cff98 100644
--- a/packages/cli/src/commands/deploy.ts
+++ b/packages/cli/src/commands/deploy.ts
@@ -397,14 +397,22 @@ export async function deployCommand(folderPath: string, options: DeployOptions =
     logger.gray(`  URL: ${existingConfig.url}`);
     logger.gray(`  Last deployed: ${existingConfig.lastDeployedAt}\n`);
 
-    const choice = await select({
-      message: 'What would you like to do?',
-      choices: [
-        { value: 'update', name: `Update existing deployment '${existingConfig.projectName}'` },
-        { value: 'new', name: 'Create a new project with a random name' },
-        { value: 'cancel', name: 'Cancel deployment' },
-      ],
-    });
+    let choice: 'update' | 'new' | 'cancel';
+
+    if (options.skipConfirm) {
+      // Non-interactive: auto-update
+      choice = 'update';
+      logger.info('Auto-updating existing deployment (--yes flag)\n');
+    } else {
+      choice = await select({
+        message: 'What would you like to do?',
+        choices: [
+          { value: 'update', name: `Update existing deployment '${existingConfig.projectName}'` },
+          { value: 'new', name: 'Create a new project with a random name' },
+          { value: 'cancel', name: 'Cancel deployment' },
+        ],
+      });
+    }
 
     if (choice === 'cancel') {
       logger.gray('\nDeployment cancelled.\n');
@@ -416,8 +424,10 @@ export async function deployCommand(folderPath: string, options: DeployOptions =
       projectName = existingConfig.projectName;
       subdomain = existingConfig.subdomain;
       isUpdate = true;
-      logger.warn('\nUpdating existing deployment...');
-      logger.gray('The previous version will be replaced.\n');
+      if (!options.skipConfirm) {
+        logger.warn('\nUpdating existing deployment...');
+        logger.gray('The previous version will be replaced.\n');
+      }
     } else {
       // Generate new random name
       projectName = generateProjectName();
@@ -456,14 +466,22 @@ export async function deployCommand(folderPath: string, options: DeployOptions =
     if (matchingProject) {
       logger.warn(`Project '${folderName}' already exists.\n`);
 
-      const choice = await select({
-        message: 'What would you like to do?',
-        choices: [
-          { value: 'update', name: `Update existing project '${folderName}'` },
-          { value: 'new', name: 'Create a new project with a random name' },
-          { value: 'cancel', name: 'Cancel deployment' },
-        ],
-      });
+      let choice: 'update' | 'new' | 'cancel';
+
+      if (options.skipConfirm) {
+        // Non-interactive: auto-update
+        choice = 'update';
+        logger.info('Auto-updating existing project (--yes flag)\n');
+      } else {
+        choice = await select({
+          message: 'What would you like to do?',
+          choices: [
+            { value: 'update', name: `Update existing project '${folderName}'` },
+            { value: 'new', name: 'Create a new project with a random name' },
+            { value: 'cancel', name: 'Cancel deployment' },
+          ],
+        });
+      }
 
       if (choice === 'cancel') {
         logger.gray('\nDeployment cancelled.\n');
@@ -474,8 +492,10 @@ export async function deployCommand(folderPath: string, options: DeployOptions =
         existingProject = matchingProject;
         projectName = matchingProject.name;
         isUpdate = true;
-        logger.warn('\nWARNING: This will replace the existing deployment.');
-        logger.gray('The previous version will be overwritten.\n');
+        if (!options.skipConfirm) {
+          logger.warn('\nWARNING: This will replace the existing deployment.');
+          logger.gray('The previous version will be overwritten.\n');
+        }
       } else {
         // Generate new random name
         projectName = generateProjectName();