diff --git a/lib/provider-detection.js b/lib/provider-detection.js
index 69526496..d2f1f930 100644
--- a/lib/provider-detection.js
+++ b/lib/provider-detection.js
@@ -1,14 +1,19 @@
-const { execSync, spawnSync } = require('child_process');
+const childProcess = require('child_process');
+const { execSync, spawnSync } = childProcess;
 const fs = require('fs');
 const path = require('path');
 
+function commandLookupCommand(command) {
+  return process.platform === 'win32' ? `where ${command}` : `command -v ${command}`;
+}
+
 function commandExists(command) {
   if (!command) return false;
   if (command.includes(path.sep)) {
     return fs.existsSync(command);
   }
   try {
-    execSync(`command -v ${command}`, { stdio: 'pipe' });
+    execSync(commandLookupCommand(command), { stdio: 'pipe' });
     return true;
   } catch {
     return false;
@@ -21,7 +26,7 @@ function getCommandPath(command) {
     return fs.existsSync(command) ? command : null;
   }
   try {
-    const output = execSync(`command -v ${command}`, { encoding: 'utf8', stdio: 'pipe' });
+    const output = execSync(commandLookupCommand(command), { encoding: 'utf8', stdio: 'pipe' });
     return output.trim() || null;
   } catch {
     return null;
@@ -56,4 +61,5 @@ module.exports = {
   getCommandPath,
   getHelpOutput,
   getVersionOutput,
+  commandLookupCommand,
 };
diff --git a/src/agent/agent-task-executor.js b/src/agent/agent-task-executor.js
index 5bc4cd77..13ab92fd 100644
--- a/src/agent/agent-task-executor.js
+++ b/src/agent/agent-task-executor.js
@@ -727,6 +727,7 @@ function spawnTaskProcess({ agent, ctPath, args, cwd, spawnEnv }) {
       cwd,
       stdio: ['ignore', 'pipe', 'pipe'],
       env: spawnEnv,
+      windowsHide: true,
     });
 
     // NOTE: Don't emit PROCESS_SPAWNED here - proc.pid is a wrapper that exits immediately.
diff --git a/src/claude-task-runner.js b/src/claude-task-runner.js
index eb03b107..2cef56ec 100644
--- a/src/claude-task-runner.js
+++ b/src/claude-task-runner.js
@@ -200,6 +200,7 @@ class ClaudeTaskRunner extends TaskRunner {
         cwd,
         stdio: ['ignore', 'pipe', 'pipe'],
         env: spawnEnv,
+        windowsHide: true,
       });
 
       let stdout = '';
diff --git a/task-lib/runner.js b/task-lib/runner.js
index 807008c7..0d68bf7b 100644
--- a/task-lib/runner.js
+++ b/task-lib/runner.js
@@ -173,6 +173,7 @@ function spawnWatcher({ watcherScript, id, cwd, logFile, finalArgs, watcherConfi
     {
       detached: true,
       stdio: 'ignore',
+      windowsHide: true,
     }
   );
 
diff --git a/task-lib/watcher.js b/task-lib/watcher.js
index ea36169b..051e5e16 100644
--- a/task-lib/watcher.js
+++ b/task-lib/watcher.js
@@ -37,6 +37,7 @@ const child = spawn(command, finalArgs, {
   cwd,
   env,
   stdio: ['ignore', 'pipe', 'pipe'],
+  windowsHide: true,
 });
 
 updateTask(taskId, { pid: child.pid });
diff --git a/tests/providers/detection.test.js b/tests/providers/detection.test.js
index ef02018d..d6f73ae7 100644
--- a/tests/providers/detection.test.js
+++ b/tests/providers/detection.test.js
@@ -1,9 +1,11 @@
 const assert = require('assert');
+const sinon = require('sinon');
 const {
   commandExists,
   getCommandPath,
   getHelpOutput,
   getVersionOutput,
+  commandLookupCommand,
 } = require('../../lib/provider-detection');
 
 describe('Provider CLI detection', () => {
@@ -28,3 +30,21 @@ describe('Provider CLI detection', () => {
     assert.ok(version.length > 0);
   });
 });
+
+describe('commandLookupCommand', () => {
+  let platformStub;
+
+  afterEach(() => {
+    if (platformStub) platformStub.restore();
+  });
+
+  it('uses where on Windows', () => {
+    platformStub = sinon.stub(process, 'platform').value('win32');
+    assert.strictEqual(commandLookupCommand('claude'), 'where claude');
+  });
+
+  it('uses command -v on non-Windows platforms', () => {
+    platformStub = sinon.stub(process, 'platform').value('linux');
+    assert.strictEqual(commandLookupCommand('claude'), 'command -v claude');
+  });
+});