diff --git a/internal/agent/hermes/command.go b/internal/agent/hermes/command.go
index b7e9423..d906715 100644
--- a/internal/agent/hermes/command.go
+++ b/internal/agent/hermes/command.go
@@ -15,14 +15,17 @@ func shellQuote(s string) string {
 //
 // agentSessionID is the hermes session ID (Session.AgentSessionID). On
 // resume:
-//   - if non-empty: `hermes --resume <id>`
-//   - if empty:     `hermes -c` (continue most-recent)
+//   - if non-empty: `hermes --tui --resume <id>`
+//   - if empty:     `hermes --tui -c` (continue most-recent)
 //
-// In both resume branches the command falls back to a fresh `hermes` on
-// non-zero exit — matches codex's pattern for crash/Ctrl-C parity.
+// In both resume branches the command falls back to a fresh `hermes --tui`
+// on non-zero exit — matches codex's pattern for crash/Ctrl-C parity.
 // (Hermes itself exits 0 even on bad ID, so this fallback is purely
 // defensive against crashes during resume.)
 //
+// --tui is always passed: ctm only ever drives hermes through its TUI
+// surface.
+//
 // envExports, when non-empty, is prepended verbatim as a shell prelude.
 func BuildCommand(agentSessionID, mode string, resume bool, envExports string) string {
 	var yoloFlag string
@@ -30,17 +33,17 @@ func BuildCommand(agentSessionID, mode string, resume bool, envExports string) s
 		yoloFlag = " --yolo"
 	}
 
-	freshCmd := "hermes" + yoloFlag
+	freshCmd := "hermes --tui" + yoloFlag
 
 	var core string
 	switch {
 	case !resume:
 		core = freshCmd
 	case agentSessionID != "":
-		core = fmt.Sprintf("hermes --resume %s%s || %s",
+		core = fmt.Sprintf("hermes --tui --resume %s%s || %s",
 			shellQuote(agentSessionID), yoloFlag, freshCmd)
 	default:
-		core = "hermes -c" + yoloFlag + " || " + freshCmd
+		core = "hermes --tui -c" + yoloFlag + " || " + freshCmd
 	}
 
 	if envExports != "" {
diff --git a/internal/agent/hermes/command_test.go b/internal/agent/hermes/command_test.go
index 6e865e7..5ed2f3a 100644
--- a/internal/agent/hermes/command_test.go
+++ b/internal/agent/hermes/command_test.go
@@ -14,53 +14,53 @@ func TestBuildCommand(t *testing.T) {
 		{
 			name: "fresh-safe",
 			mode: "safe", resume: false,
-			want: "hermes",
+			want: "hermes --tui",
 		},
 		{
 			name: "fresh-yolo",
 			mode: "yolo", resume: false,
-			want: "hermes --yolo",
+			want: "hermes --tui --yolo",
 		},
 		{
 			name:           "resume-with-id-safe",
 			agentSessionID: "20260515_152727_9da209",
 			mode:           "safe", resume: true,
-			want: "hermes --resume '20260515_152727_9da209' || hermes",
+			want: "hermes --tui --resume '20260515_152727_9da209' || hermes --tui",
 		},
 		{
 			name:           "resume-with-id-yolo",
 			agentSessionID: "20260515_152727_9da209",
 			mode:           "yolo", resume: true,
-			want: "hermes --resume '20260515_152727_9da209' --yolo || hermes --yolo",
+			want: "hermes --tui --resume '20260515_152727_9da209' --yolo || hermes --tui --yolo",
 		},
 		{
 			name: "resume-no-id-safe",
 			mode: "safe", resume: true,
-			want: "hermes -c || hermes",
+			want: "hermes --tui -c || hermes --tui",
 		},
 		{
 			name: "resume-no-id-yolo",
 			mode: "yolo", resume: true,
-			want: "hermes -c --yolo || hermes --yolo",
+			want: "hermes --tui -c --yolo || hermes --tui --yolo",
 		},
 		{
 			name: "env-prelude-fresh-safe",
 			mode: "safe", resume: false,
 			envExports: "export FOO='bar'",
-			want:       "export FOO='bar'; hermes",
+			want:       "export FOO='bar'; hermes --tui",
 		},
 		{
 			name:           "env-prelude-resume-yolo",
 			agentSessionID: "id1",
 			mode:           "yolo", resume: true,
 			envExports: "export FOO='bar'",
-			want:       "export FOO='bar'; hermes --resume 'id1' --yolo || hermes --yolo",
+			want:       "export FOO='bar'; hermes --tui --resume 'id1' --yolo || hermes --tui --yolo",
 		},
 		{
 			name:           "shell-quote-escapes-single-quote",
 			agentSessionID: `weird'id`,
 			mode:           "safe", resume: true,
-			want: `hermes --resume 'weird'\''id' || hermes`,
+			want: `hermes --tui --resume 'weird'\''id' || hermes --tui`,
 		},
 	}
 	for _, tt := range tests {