diff --git a/.gitignore b/.gitignore
index 31995b5..514307f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,3 +8,4 @@ __pycache__
 .coverage
 coverage.out
 references
+output/
diff --git a/codeagent-wrapper/internal/app/executor_concurrent_test.go b/codeagent-wrapper/internal/app/executor_concurrent_test.go
index db0fc74..f6c7e8b 100644
--- a/codeagent-wrapper/internal/app/executor_concurrent_test.go
+++ b/codeagent-wrapper/internal/app/executor_concurrent_test.go
@@ -567,8 +567,7 @@ func TestExecutorParallelLogIsolation(t *testing.T) {
 }
 
 func TestConcurrentExecutorParallelLogIsolationAndClosure(t *testing.T) {
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	setTempDirEnv(t, t.TempDir())
 
 	oldArgs := os.Args
 	os.Args = []string{wrapperName}
@@ -929,8 +928,7 @@ func TestExecutorExecuteConcurrentWithContextBranches(t *testing.T) {
 	t.Run("TestConcurrentTaskLoggerFailure", func(t *testing.T) {
 		// Create a writable temp dir for the main logger, then flip TMPDIR to a read-only
 		// location so task-specific loggers fail to open.
-		writable := t.TempDir()
-		t.Setenv("TMPDIR", writable)
+		writable := setTempDirEnv(t, t.TempDir())
 
 		mainLogger, err := NewLoggerWithSuffix("shared-main")
 		if err != nil {
@@ -943,11 +941,11 @@ func TestExecutorExecuteConcurrentWithContextBranches(t *testing.T) {
 			_ = os.Remove(mainLogger.Path())
 		})
 
-		noWrite := filepath.Join(writable, "ro")
-		if err := os.Mkdir(noWrite, 0o500); err != nil {
-			t.Fatalf("failed to create read-only temp dir: %v", err)
+		notDir := filepath.Join(writable, "not-a-dir")
+		if err := os.WriteFile(notDir, []byte("x"), 0o644); err != nil {
+			t.Fatalf("failed to create temp file: %v", err)
 		}
-		t.Setenv("TMPDIR", noWrite)
+		setTempDirEnv(t, notDir)
 
 		taskA := nextExecutorTestTaskID("shared-a")
 		taskB := nextExecutorTestTaskID("shared-b")
@@ -1011,8 +1009,7 @@ func TestExecutorExecuteConcurrentWithContextBranches(t *testing.T) {
 	})
 
 	t.Run("TestSanitizeTaskID", func(t *testing.T) {
-		tempDir := t.TempDir()
-		t.Setenv("TMPDIR", tempDir)
+		setTempDirEnv(t, t.TempDir())
 
 		orig := runCodexTaskFn
 		runCodexTaskFn = func(task TaskSpec, timeout int) TaskResult {
@@ -1081,8 +1078,7 @@ func TestExecutorSharedLogFalseWhenCustomLogPath(t *testing.T) {
 		_ = devNull.Close()
 	})
 
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	tempDir := setTempDirEnv(t, t.TempDir())
 
 	// Setup: 创建主 logger
 	mainLogger, err := NewLoggerWithSuffix("shared-main")
@@ -1098,11 +1094,11 @@ func TestExecutorSharedLogFalseWhenCustomLogPath(t *testing.T) {
 	// 模拟场景：task logger 创建失败（通过设置只读的 TMPDIR），
 	// 回退到主 logger（handle.shared=true），
 	// 但 runCodexTaskFn 返回自定义的 LogPath（不等于主 logger 的路径）
-	roDir := filepath.Join(tempDir, "ro")
-	if err := os.Mkdir(roDir, 0o500); err != nil {
-		t.Fatalf("failed to create read-only dir: %v", err)
+	notDir := filepath.Join(tempDir, "not-a-dir")
+	if err := os.WriteFile(notDir, []byte("x"), 0o644); err != nil {
+		t.Fatalf("failed to create temp file: %v", err)
 	}
-	t.Setenv("TMPDIR", roDir)
+	setTempDirEnv(t, notDir)
 
 	orig := runCodexTaskFn
 	customLogPath := "/custom/path/to.log"
diff --git a/codeagent-wrapper/internal/app/main_integration_test.go b/codeagent-wrapper/internal/app/main_integration_test.go
index 0b39a7c..79e8be5 100644
--- a/codeagent-wrapper/internal/app/main_integration_test.go
+++ b/codeagent-wrapper/internal/app/main_integration_test.go
@@ -725,20 +725,18 @@ func TestRunConcurrentSpeedupBenchmark(t *testing.T) {
 	layers := [][]TaskSpec{tasks}
 
 	serialStart := time.Now()
-	for _, task := range tasks {
-		_ = runCodexTaskFn(task, 5)
-	}
+	_ = executeConcurrentWithContext(nil, layers, 5, 1)
 	serialElapsed := time.Since(serialStart)
 
 	concurrentStart := time.Now()
-	_ = executeConcurrent(layers, 5)
+	_ = executeConcurrentWithContext(nil, layers, 5, 0)
 	concurrentElapsed := time.Since(concurrentStart)
 
-	if concurrentElapsed >= serialElapsed/5 {
-		t.Fatalf("expected concurrent time <20%% of serial, serial=%v concurrent=%v", serialElapsed, concurrentElapsed)
-	}
 	ratio := float64(concurrentElapsed) / float64(serialElapsed)
 	t.Logf("speedup ratio (concurrent/serial)=%.3f", ratio)
+	if concurrentElapsed >= serialElapsed/2 {
+		t.Fatalf("expected concurrent time <50%% of serial, serial=%v concurrent=%v", serialElapsed, concurrentElapsed)
+	}
 }
 
 func TestRunStartupCleanupRemovesOrphansEndToEnd(t *testing.T) {
diff --git a/codeagent-wrapper/internal/app/main_test.go b/codeagent-wrapper/internal/app/main_test.go
index aebce67..3bf3da9 100644
--- a/codeagent-wrapper/internal/app/main_test.go
+++ b/codeagent-wrapper/internal/app/main_test.go
@@ -1948,7 +1948,7 @@ func TestRun_PassesReasoningEffortToTaskSpec(t *testing.T) {
 func TestRun_NoOutputMessage_ReturnsExitCode1AndWritesStderr(t *testing.T) {
 	defer resetTestHooks()
 	cleanupLogsFn = func() (CleanupStats, error) { return CleanupStats{}, nil }
-	t.Setenv("TMPDIR", t.TempDir())
+	setTempDirEnv(t, t.TempDir())
 
 	selectBackendFn = func(name string) (Backend, error) {
 		return testBackend{name: name, command: "echo"}, nil
@@ -2099,8 +2099,7 @@ func TestRunBuildCodexArgs_ResumeMode_EmptySessionHandledGracefully(t *testing.T
 
 func TestRunBuildCodexArgs_BypassSandboxEnvTrue(t *testing.T) {
 	defer resetTestHooks()
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	setTempDirEnv(t, t.TempDir())
 
 	logger, err := NewLogger()
 	if err != nil {
@@ -2744,8 +2743,7 @@ func TestTailBufferWrite(t *testing.T) {
 
 func TestRunLogFunctions(t *testing.T) {
 	defer resetTestHooks()
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	setTempDirEnv(t, t.TempDir())
 
 	logger, err := NewLogger()
 	if err != nil {
@@ -2792,8 +2790,7 @@ func TestLoggerLogDropOnDone(t *testing.T) {
 
 func TestLoggerLogAfterClose(t *testing.T) {
 	defer resetTestHooks()
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	setTempDirEnv(t, t.TempDir())
 
 	logger, err := NewLogger()
 	if err != nil {
@@ -4243,8 +4240,7 @@ func TestRun_ExplicitStdinEmpty(t *testing.T) {
 
 func TestRun_ExplicitStdinReadError(t *testing.T) {
 	defer resetTestHooks()
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	tempDir := setTempDirEnv(t, t.TempDir())
 	logPath := filepath.Join(tempDir, fmt.Sprintf("codeagent-wrapper-%d.log", os.Getpid()))
 
 	var logOutput string
@@ -4340,8 +4336,7 @@ func TestRun_ExplicitStdinSuccess(t *testing.T) {
 
 func TestRun_PipedTaskReadError(t *testing.T) {
 	defer resetTestHooks()
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	tempDir := setTempDirEnv(t, t.TempDir())
 	logPath := filepath.Join(tempDir, fmt.Sprintf("codeagent-wrapper-%d.log", os.Getpid()))
 
 	var logOutput string
@@ -4394,8 +4389,7 @@ func TestRun_PipedTaskSuccess(t *testing.T) {
 
 func TestRun_LoggerLifecycle(t *testing.T) {
 	defer resetTestHooks()
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	tempDir := setTempDirEnv(t, t.TempDir())
 	logPath := filepath.Join(tempDir, fmt.Sprintf("codeagent-wrapper-%d.log", os.Getpid()))
 
 	stdout := captureStdoutPipe()
@@ -4443,8 +4437,7 @@ func TestRun_LoggerRemovedOnSignal(t *testing.T) {
 	// Set shorter delays for faster test
 	_ = executor.SetForceKillDelay(1)
 
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	tempDir := setTempDirEnv(t, t.TempDir())
 	logPath := filepath.Join(tempDir, fmt.Sprintf("codeagent-wrapper-%d.log", os.Getpid()))
 
 	scriptPath := filepath.Join(tempDir, "sleepy-codex.sh")
@@ -4728,8 +4721,7 @@ func TestBackendRunCoverage(t *testing.T) {
 func TestParallelLogPathInSerialMode(t *testing.T) {
 	defer resetTestHooks()
 
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	tempDir := setTempDirEnv(t, t.TempDir())
 
 	os.Args = []string{"codeagent-wrapper", "do-stuff"}
 	stdinReader = strings.NewReader("")
diff --git a/codeagent-wrapper/internal/app/stdin_mode_test.go b/codeagent-wrapper/internal/app/stdin_mode_test.go
index 8b659a9..9049c28 100644
--- a/codeagent-wrapper/internal/app/stdin_mode_test.go
+++ b/codeagent-wrapper/internal/app/stdin_mode_test.go
@@ -8,7 +8,7 @@ import (
 func TestRunSingleMode_UseStdin_TargetArgAndTaskText(t *testing.T) {
 	defer resetTestHooks()
 
-	t.Setenv("TMPDIR", t.TempDir())
+	setTempDirEnv(t, t.TempDir())
 	logger, err := NewLogger()
 	if err != nil {
 		t.Fatalf("NewLogger(): %v", err)
diff --git a/codeagent-wrapper/internal/executor/env_inject_test.go b/codeagent-wrapper/internal/executor/env_inject_test.go
index 16d7cf1..089e379 100644
--- a/codeagent-wrapper/internal/executor/env_inject_test.go
+++ b/codeagent-wrapper/internal/executor/env_inject_test.go
@@ -36,10 +36,8 @@ func TestEnvInjectionWithAgent(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	// Override HOME to use temp dir
-	oldHome := os.Getenv("HOME")
-	os.Setenv("HOME", tmpDir)
-	defer os.Setenv("HOME", oldHome)
+	t.Setenv("HOME", tmpDir)
+	t.Setenv("USERPROFILE", tmpDir)
 
 	// Reset config cache
 	config.ResetModelsConfigCacheForTest()
@@ -104,9 +102,8 @@ func TestEnvInjectionLogic(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	oldHome := os.Getenv("HOME")
-	os.Setenv("HOME", tmpDir)
-	defer os.Setenv("HOME", oldHome)
+	t.Setenv("HOME", tmpDir)
+	t.Setenv("USERPROFILE", tmpDir)
 
 	config.ResetModelsConfigCacheForTest()
 	defer config.ResetModelsConfigCacheForTest()
diff --git a/codeagent-wrapper/internal/executor/env_stderr_test.go b/codeagent-wrapper/internal/executor/env_stderr_test.go
index 0b9baa1..9c9c2b7 100644
--- a/codeagent-wrapper/internal/executor/env_stderr_test.go
+++ b/codeagent-wrapper/internal/executor/env_stderr_test.go
@@ -65,11 +65,8 @@ func TestEnvInjection_LogsToStderrAndMasksKey(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	oldHome := os.Getenv("HOME")
-	if err := os.Setenv("HOME", tmpDir); err != nil {
-		t.Fatal(err)
-	}
-	defer func() { _ = os.Setenv("HOME", oldHome) }()
+	t.Setenv("HOME", tmpDir)
+	t.Setenv("USERPROFILE", tmpDir)
 
 	config.ResetModelsConfigCacheForTest()
 	defer config.ResetModelsConfigCacheForTest()
diff --git a/codeagent-wrapper/internal/executor/executor.go b/codeagent-wrapper/internal/executor/executor.go
index db5e8f9..14acccb 100644
--- a/codeagent-wrapper/internal/executor/executor.go
+++ b/codeagent-wrapper/internal/executor/executor.go
@@ -8,6 +8,7 @@ import (
 	"os"
 	"os/exec"
 	"os/signal"
+	"runtime"
 	"sort"
 	"strings"
 	"sync"
@@ -253,6 +254,15 @@ func (p *realProcess) Signal(sig os.Signal) error {
 
 // newCommandRunner creates a new commandRunner (test hook injection point)
 var newCommandRunner = func(ctx context.Context, name string, args ...string) commandRunner {
+	if runtime.GOOS == "windows" {
+		lowerName := strings.ToLower(strings.TrimSpace(name))
+		if strings.HasSuffix(lowerName, ".bat") || strings.HasSuffix(lowerName, ".cmd") {
+			cmdArgs := make([]string, 0, 2+len(args))
+			cmdArgs = append(cmdArgs, "/c", name)
+			cmdArgs = append(cmdArgs, args...)
+			return &realCmd{cmd: commandContext(ctx, "cmd.exe", cmdArgs...)}
+		}
+	}
 	return &realCmd{cmd: commandContext(ctx, name, args...)}
 }
 
@@ -1058,17 +1068,17 @@ func RunCodexTaskWithContext(parentCtx context.Context, taskSpec TaskSpec, backe
 	}
 
 	if envBackend != nil {
-			baseURL, apiKey := config.ResolveBackendConfig(cfg.Backend)
-			if agentName := strings.TrimSpace(taskSpec.Agent); agentName != "" {
-				agentBackend, _, _, _, agentBaseURL, agentAPIKey, _, err := config.ResolveAgentConfig(agentName)
-				if err == nil {
-					if strings.EqualFold(strings.TrimSpace(agentBackend), strings.TrimSpace(cfg.Backend)) {
-						baseURL, apiKey = agentBaseURL, agentAPIKey
-					}
+		baseURL, apiKey := config.ResolveBackendConfig(cfg.Backend)
+		if agentName := strings.TrimSpace(taskSpec.Agent); agentName != "" {
+			agentBackend, _, _, _, agentBaseURL, agentAPIKey, _, err := config.ResolveAgentConfig(agentName)
+			if err == nil {
+				if strings.EqualFold(strings.TrimSpace(agentBackend), strings.TrimSpace(cfg.Backend)) {
+					baseURL, apiKey = agentBaseURL, agentAPIKey
 				}
 			}
-			if injected := envBackend.Env(baseURL, apiKey); len(injected) > 0 {
-				cmd.SetEnv(injected)
+		}
+		if injected := envBackend.Env(baseURL, apiKey); len(injected) > 0 {
+			cmd.SetEnv(injected)
 			// Log injected env vars with masked API keys (to file and stderr)
 			for k, v := range injected {
 				msg := fmt.Sprintf("Env: %s=%s", k, maskSensitiveValue(k, v))
diff --git a/codeagent-wrapper/internal/logger/logger_suffix_test.go b/codeagent-wrapper/internal/logger/logger_suffix_test.go
index dffbfbd..48e6ec4 100644
--- a/codeagent-wrapper/internal/logger/logger_suffix_test.go
+++ b/codeagent-wrapper/internal/logger/logger_suffix_test.go
@@ -70,12 +70,11 @@ func TestLoggerWithSuffixNamingAndIsolation(t *testing.T) {
 
 func TestLoggerWithSuffixReturnsErrorWhenTempDirNotWritable(t *testing.T) {
 	base := t.TempDir()
-	noWrite := filepath.Join(base, "ro")
-	if err := os.Mkdir(noWrite, 0o500); err != nil {
-		t.Fatalf("failed to create read-only temp dir: %v", err)
+	notDir := filepath.Join(base, "not-a-dir")
+	if err := os.WriteFile(notDir, []byte("x"), 0o644); err != nil {
+		t.Fatalf("failed to create temp file: %v", err)
 	}
-	t.Cleanup(func() { _ = os.Chmod(noWrite, 0o700) })
-	setTempDirEnv(t, noWrite)
+	setTempDirEnv(t, notDir)
 
 	logger, err := NewLoggerWithSuffix("task-err")
 	if err == nil {
diff --git a/codeagent-wrapper/internal/logger/logger_test.go b/codeagent-wrapper/internal/logger/logger_test.go
index 6061f1b..5fbe217 100644
--- a/codeagent-wrapper/internal/logger/logger_test.go
+++ b/codeagent-wrapper/internal/logger/logger_test.go
@@ -26,8 +26,7 @@ func compareCleanupStats(got, want CleanupStats) bool {
 }
 
 func TestLoggerCreatesFileWithPID(t *testing.T) {
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	tempDir := setTempDirEnv(t, t.TempDir())
 
 	logger, err := NewLogger()
 	if err != nil {
@@ -46,8 +45,7 @@ func TestLoggerCreatesFileWithPID(t *testing.T) {
 }
 
 func TestLoggerWritesLevels(t *testing.T) {
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	setTempDirEnv(t, t.TempDir())
 
 	logger, err := NewLogger()
 	if err != nil {
@@ -77,8 +75,7 @@ func TestLoggerWritesLevels(t *testing.T) {
 }
 
 func TestLoggerCloseStopsWorkerAndKeepsFile(t *testing.T) {
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	setTempDirEnv(t, t.TempDir())
 
 	logger, err := NewLogger()
 	if err != nil {
@@ -104,8 +101,7 @@ func TestLoggerCloseStopsWorkerAndKeepsFile(t *testing.T) {
 }
 
 func TestLoggerConcurrentWritesSafe(t *testing.T) {
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	setTempDirEnv(t, t.TempDir())
 
 	logger, err := NewLogger()
 	if err != nil {
@@ -390,12 +386,14 @@ func TestLoggerCleanupOldLogsPerformanceBound(t *testing.T) {
 	fakePaths := make([]string, fileCount)
 	for i := 0; i < fileCount; i++ {
 		name := fmt.Sprintf("codeagent-wrapper-%d.log", 10000+i)
-		fakePaths[i] = createTempLog(t, tempDir, name)
+		fakePaths[i] = filepath.Join(tempDir, name)
 	}
 
 	stubGlobLogFiles(t, func(pattern string) ([]string, error) {
 		return fakePaths, nil
 	})
+	stubFileStat(t, func(string) (os.FileInfo, error) { return fakeFileInfo{}, nil })
+	stubEvalSymlinks(t, func(path string) (string, error) { return path, nil })
 	stubProcessRunning(t, func(int) bool { return false })
 	stubProcessStartTime(t, func(int) time.Time { return time.Time{} })
 
@@ -542,8 +540,7 @@ func TestLoggerIsUnsafeFileSecurityChecks(t *testing.T) {
 }
 
 func TestLoggerPathAndRemove(t *testing.T) {
-	tempDir := t.TempDir()
-	t.Setenv("TMPDIR", tempDir)
+	setTempDirEnv(t, t.TempDir())
 
 	logger, err := NewLoggerWithSuffix("sample")
 	if err != nil {