diff --git a/internal/agent/codex.go b/internal/agent/codex.go
index cbd7482..1e95336 100644
--- a/internal/agent/codex.go
+++ b/internal/agent/codex.go
@@ -32,7 +32,7 @@ func (p *CodexProvider) CLIPath() string { return p.cliPath }
 
 // LoopCommand implements loop.Provider.
 func (p *CodexProvider) LoopCommand(ctx context.Context, prompt, workDir string) *exec.Cmd {
-	cmd := exec.CommandContext(ctx, p.cliPath, "exec", "--json", "--yolo", "-C", workDir, "-")
+	cmd := exec.CommandContext(ctx, p.cliPath, "exec", "--json", "--yolo", "--skip-git-repo-check", "-C", workDir, "-")
 	cmd.Dir = workDir
 	cmd.Stdin = strings.NewReader(prompt)
 	return cmd
@@ -52,8 +52,10 @@ func (p *CodexProvider) ConvertCommand(workDir, prompt string) (*exec.Cmd, loop.
 		return nil, 0, "", fmt.Errorf("failed to create temp file for conversion output: %w", err)
 	}
 	outPath := f.Name()
-	f.Close()
-	cmd := exec.Command(p.cliPath, "exec", "--sandbox", "read-only", "-o", outPath, "-")
+	if err := f.Close(); err != nil {
+		return nil, 0, "", fmt.Errorf("failed to close temp file for conversion output: %w", err)
+	}
+	cmd := exec.Command(p.cliPath, "exec", "--sandbox", "read-only", "--skip-git-repo-check", "-o", outPath, "-")
 	cmd.Dir = workDir
 	cmd.Stdin = strings.NewReader(prompt)
 	return cmd, loop.OutputFromFile, outPath, nil
@@ -66,8 +68,10 @@ func (p *CodexProvider) FixJSONCommand(prompt string) (*exec.Cmd, loop.OutputMod
 		return nil, 0, "", fmt.Errorf("failed to create temp file for fix output: %w", err)
 	}
 	outPath := f.Name()
-	f.Close()
-	cmd := exec.Command(p.cliPath, "exec", "--sandbox", "read-only", "-o", outPath, "-")
+	if err := f.Close(); err != nil {
+		return nil, 0, "", fmt.Errorf("failed to close temp file for fix output: %w", err)
+	}
+	cmd := exec.Command(p.cliPath, "exec", "--sandbox", "read-only", "--skip-git-repo-check", "-o", outPath, "-")
 	cmd.Stdin = strings.NewReader(prompt)
 	return cmd, loop.OutputFromFile, outPath, nil
 }
diff --git a/internal/agent/codex_test.go b/internal/agent/codex_test.go
index 3a9d2c0..5ed1ec9 100644
--- a/internal/agent/codex_test.go
+++ b/internal/agent/codex_test.go
@@ -41,7 +41,7 @@ func TestCodexProvider_LoopCommand(t *testing.T) {
 	if cmd.Path != "/bin/codex" {
 		t.Errorf("LoopCommand Path = %q, want /bin/codex", cmd.Path)
 	}
-	wantArgs := []string{"/bin/codex", "exec", "--json", "--yolo", "-C", "/work/dir", "-"}
+	wantArgs := []string{"/bin/codex", "exec", "--json", "--yolo", "--skip-git-repo-check", "-C", "/work/dir", "-"}
 	if len(cmd.Args) != len(wantArgs) {
 		t.Fatalf("LoopCommand Args len = %d, want %d: %v", len(cmd.Args), len(wantArgs), cmd.Args)
 	}
@@ -76,15 +76,21 @@ func TestCodexProvider_ConvertCommand(t *testing.T) {
 		t.Errorf("ConvertCommand Path = %q", cmd.Path)
 	}
 	foundO := false
+	foundSkipGitRepoCheck := false
 	for i, a := range cmd.Args {
 		if a == "-o" && i+1 < len(cmd.Args) && cmd.Args[i+1] == outPath {
 			foundO = true
-			break
+		}
+		if a == "--skip-git-repo-check" {
+			foundSkipGitRepoCheck = true
 		}
 	}
 	if !foundO {
 		t.Errorf("ConvertCommand should have -o %q in args: %v", outPath, cmd.Args)
 	}
+	if !foundSkipGitRepoCheck {
+		t.Errorf("ConvertCommand should include --skip-git-repo-check: %v", cmd.Args)
+	}
 	if cmd.Dir != "/prd/dir" {
 		t.Errorf("ConvertCommand Dir = %q, want /prd/dir", cmd.Dir)
 	}
@@ -103,15 +109,21 @@ func TestCodexProvider_FixJSONCommand(t *testing.T) {
 		t.Error("FixJSONCommand outPath should be non-empty temp file")
 	}
 	foundO := false
+	foundSkipGitRepoCheck := false
 	for i, a := range cmd.Args {
 		if a == "-o" && i+1 < len(cmd.Args) && cmd.Args[i+1] == outPath {
 			foundO = true
-			break
+		}
+		if a == "--skip-git-repo-check" {
+			foundSkipGitRepoCheck = true
 		}
 	}
 	if !foundO {
 		t.Errorf("FixJSONCommand should have -o %q in args: %v", outPath, cmd.Args)
 	}
+	if !foundSkipGitRepoCheck {
+		t.Errorf("FixJSONCommand should include --skip-git-repo-check: %v", cmd.Args)
+	}
 }
 
 func TestCodexProvider_InteractiveCommand(t *testing.T) {
@@ -120,8 +132,14 @@ func TestCodexProvider_InteractiveCommand(t *testing.T) {
 	if cmd.Dir != "/work" {
 		t.Errorf("InteractiveCommand Dir = %q, want /work", cmd.Dir)
 	}
-	if len(cmd.Args) < 2 || cmd.Args[0] != "codex" || cmd.Args[1] != "my prompt" {
-		t.Errorf("InteractiveCommand Args = %v", cmd.Args)
+	wantArgs := []string{"codex", "my prompt"}
+	if len(cmd.Args) != len(wantArgs) {
+		t.Fatalf("InteractiveCommand Args len = %d, want %d: %v", len(cmd.Args), len(wantArgs), cmd.Args)
+	}
+	for i, w := range wantArgs {
+		if cmd.Args[i] != w {
+			t.Errorf("InteractiveCommand Args[%d] = %q, want %q", i, cmd.Args[i], w)
+		}
 	}
 }
 
diff --git a/internal/agent/resolve_test.go b/internal/agent/resolve_test.go
index fa199f8..2a30bda 100644
--- a/internal/agent/resolve_test.go
+++ b/internal/agent/resolve_test.go
@@ -67,37 +67,61 @@ func TestResolve_env(t *testing.T) {
 	savePath := os.Getenv(keyPath)
 	defer func() {
 		if saveAgent != "" {
-			os.Setenv(keyAgent, saveAgent)
+			if err := os.Setenv(keyAgent, saveAgent); err != nil {
+				t.Fatalf("restore %s: %v", keyAgent, err)
+			}
 		} else {
-			os.Unsetenv(keyAgent)
+			if err := os.Unsetenv(keyAgent); err != nil {
+				t.Fatalf("unset %s: %v", keyAgent, err)
+			}
 		}
 		if savePath != "" {
-			os.Setenv(keyPath, savePath)
+			if err := os.Setenv(keyPath, savePath); err != nil {
+				t.Fatalf("restore %s: %v", keyPath, err)
+			}
 		} else {
-			os.Unsetenv(keyPath)
+			if err := os.Unsetenv(keyPath); err != nil {
+				t.Fatalf("unset %s: %v", keyPath, err)
+			}
 		}
 	}()
 
-	os.Unsetenv(keyAgent)
-	os.Unsetenv(keyPath)
+	if err := os.Unsetenv(keyAgent); err != nil {
+		t.Fatalf("unset %s: %v", keyAgent, err)
+	}
+	if err := os.Unsetenv(keyPath); err != nil {
+		t.Fatalf("unset %s: %v", keyPath, err)
+	}
 
 	// Env provider when no flag
-	os.Setenv(keyAgent, "codex")
+	if err := os.Setenv(keyAgent, "codex"); err != nil {
+		t.Fatalf("set %s: %v", keyAgent, err)
+	}
 	got := mustResolve(t, "", "", nil)
 	if got.Name() != "Codex" {
 		t.Errorf("with CHIEF_AGENT=codex, name = %q, want Codex", got.Name())
 	}
-	os.Unsetenv(keyAgent)
+	if err := os.Unsetenv(keyAgent); err != nil {
+		t.Fatalf("unset %s: %v", keyAgent, err)
+	}
 
 	// Env path when no flag path
-	os.Setenv(keyAgent, "codex")
-	os.Setenv(keyPath, "/env/codex")
+	if err := os.Setenv(keyAgent, "codex"); err != nil {
+		t.Fatalf("set %s: %v", keyAgent, err)
+	}
+	if err := os.Setenv(keyPath, "/env/codex"); err != nil {
+		t.Fatalf("set %s: %v", keyPath, err)
+	}
 	got = mustResolve(t, "", "", nil)
 	if got.CLIPath() != "/env/codex" {
 		t.Errorf("with CHIEF_AGENT_PATH, CLIPath = %q, want /env/codex", got.CLIPath())
 	}
-	os.Unsetenv(keyPath)
-	os.Unsetenv(keyAgent)
+	if err := os.Unsetenv(keyPath); err != nil {
+		t.Fatalf("unset %s: %v", keyPath, err)
+	}
+	if err := os.Unsetenv(keyAgent); err != nil {
+		t.Fatalf("unset %s: %v", keyAgent, err)
+	}
 }
 
 func TestResolve_normalize(t *testing.T) {