diff --git a/tests/tui_gateway/test_bot_mode_silence_delivery.py b/tests/tui_gateway/test_bot_mode_silence_delivery.py
new file mode 100644
index 0000000000..bb481c4fb1
--- /dev/null
+++ b/tests/tui_gateway/test_bot_mode_silence_delivery.py
@@ -0,0 +1,56 @@
+"""Regression coverage for Bot Mode's shared completed-reply delivery boundary."""
+
+import contextlib
+from types import SimpleNamespace
+
+import pytest
+
+import tui_gateway.server as srv
+from tui_gateway.prompt_turn import _bot_mode_delivery_text, _is_bot_mode_session
+
+
+@pytest.mark.parametrize("response", [
+    "NO_REPLY", " [silent] ", "silent", "no reply", "*NO_REPLY*",
+])
+def test_bot_mode_delivery_hides_successful_canonical_silence_markers(response):
+    assert _bot_mode_delivery_text(response, successful=True) == ""
+
+
+@pytest.mark.parametrize("response", [
+    "The NO_REPLY marker means do not answer.",
+    "[SILENT] is mentioned here, but this is a real answer.",
+])
+def test_bot_mode_delivery_keeps_substantive_marker_mentions(response):
+    assert _bot_mode_delivery_text(response, successful=True) == response
+
+
+def test_bot_mode_delivery_keeps_failed_marker_response_visible():
+    assert _bot_mode_delivery_text("NO_REPLY", successful=False) == "NO_REPLY"
+
+
+def test_only_canonical_bot_chat_sessions_use_the_live_delivery_boundary():
+    assert _is_bot_mode_session({"pending_title": "Bot Chat"})
+    assert _is_bot_mode_session({"title": "Bot Chat"})
+    assert not _is_bot_mode_session({"pending_title": "Scratch"})
+
+
+def test_live_bot_chat_completion_suppresses_markers_but_failed_turns_fail_open(monkeypatch):
+    """The prompt.submit completion path applies the shared delivery boundary."""
+    monkeypatch.setattr(srv, "_get_usage", lambda _agent: {})
+    monkeypatch.setattr(srv, "render_message", lambda _text, _cols: None)
+    monkeypatch.setattr(srv, "_clear_inflight_turn", lambda _session: None)
+
+    session = {"pending_title": "Bot Chat", "history_lock": contextlib.nullcontext()}
+    turn = SimpleNamespace(
+        result={"final_response": "NO_REPLY"}, agent=object(), terminal_callback=None,
+        receipt_committed=True, receipt_attempted=False, marker_key="", error_retained=False,
+        error_detail="", prompt_text="ping",
+    )
+    payload, _, status = srv._complete_turn_payload(session, turn, None, 80)
+    assert status == "complete"
+    assert payload["text"] == ""
+
+    turn.result = {"final_response": "NO_REPLY", "error": "provider failed", "failed": True}
+    payload, _, status = srv._complete_turn_payload(session, turn, None, 80)
+    assert status == "error"
+    assert payload["text"] == "NO_REPLY"
diff --git a/tests/tui_gateway/test_bot_relay_methods.py b/tests/tui_gateway/test_bot_relay_methods.py
index 4ce12bf763..e5270d7cb2 100644
--- a/tests/tui_gateway/test_bot_relay_methods.py
+++ b/tests/tui_gateway/test_bot_relay_methods.py
@@ -108,6 +108,40 @@ def test_deliver_requires_params(home):
     assert "error" in err
 
 
+@pytest.mark.parametrize("reply", [
+    "NO_REPLY", " [silent] ", "silent", "no reply", "*NO_REPLY*",
+])
+def test_deliver_suppresses_successful_silence_markers(home, monkeypatch, reply):
+    """A successful subprocess relay never returns a bare silence marker to Bot Mode."""
+    class _Proc:
+        returncode = 0
+        stdout = reply
+        stderr = ""
+
+    monkeypatch.setattr("subprocess.run", lambda *_args, **_kwargs: _Proc())
+
+    out = _result(srv._methods["bot_relay.deliver"](1, {"profile": "ops", "message": "ping"}))
+
+    assert out["reply"] == ""
+
+
+@pytest.mark.parametrize("reply", [
+    "The NO_REPLY marker means do not answer.",
+    "[SILENT] is mentioned here, but this is a real answer.",
+])
+def test_deliver_keeps_substantive_marker_mentions(home, monkeypatch, reply):
+    class _Proc:
+        returncode = 0
+        stdout = reply
+        stderr = ""
+
+    monkeypatch.setattr("subprocess.run", lambda *_args, **_kwargs: _Proc())
+
+    out = _result(srv._methods["bot_relay.deliver"](1, {"profile": "ops", "message": "ping"}))
+
+    assert out["reply"] == reply
+
+
 def test_deliver_lands_in_live_bot_chat_instead_of_subprocess(home, monkeypatch):
     """#100523: a Desktop-owned Bot Chat receives the DM as a normal user turn.
 
diff --git a/tui_gateway/methods_bot_relay.py b/tui_gateway/methods_bot_relay.py
index a638654d65..082e891c80 100644
--- a/tui_gateway/methods_bot_relay.py
+++ b/tui_gateway/methods_bot_relay.py
@@ -147,7 +147,12 @@ def _(rid, params: dict, _root=_relay_root, _run=_run_delivery) -> dict:
             detail = _detail(proc)
             return _err(rid, 5092, f"delivery turn failed: {detail or proc.returncode}",
                         data={"reason": classify_agent_error(detail)})
-        return _ok(rid, {"reply": (proc.stdout or "").strip()})
+        # Use the same canonical whole-response predicate as live Bot Chat
+        # completion.  A marker remains a successful turn, but is never sent
+        # back to the relay caller as visible prose.
+        from tui_gateway.prompt_turn import _bot_mode_delivery_text
+        reply = _bot_mode_delivery_text((proc.stdout or "").strip(), successful=True)
+        return _ok(rid, {"reply": reply})
     except subprocess.TimeoutExpired:
         return _err(rid, 5093, "delivery turn timed out")
     except Exception as e:
diff --git a/tui_gateway/prompt_turn.py b/tui_gateway/prompt_turn.py
index 97f9b90fbe..6eb940abeb 100644
--- a/tui_gateway/prompt_turn.py
+++ b/tui_gateway/prompt_turn.py
@@ -16,6 +16,24 @@ from .method_ctx import HandlerRegistry, bind_module
 _registry = HandlerRegistry()
 
 
+def _bot_mode_delivery_text(response: Any, *, successful: bool) -> Any:
+    """Return the text Bot Mode may render or relay after a completed turn.
+
+    The gateway owns the canonical marker set.  Keep the row and completion
+    event intact, but make a successful bare marker invisible at every Bot
+    Mode delivery boundary.  Failed turns intentionally fail open so their
+    diagnostic text is never swallowed.
+    """
+    from gateway.response_filters import is_intentional_silence_response
+    return "" if successful and is_intentional_silence_response(response) else response
+
+
+def _is_bot_mode_session(session: dict) -> bool:
+    """Whether this completion belongs to the canonical Bot Chat surface."""
+    from tools.bot_mode_probe import BOT_CHAT_TITLE
+    return any(session.get(field) == BOT_CHAT_TITLE for field in ("pending_title", "title"))
+
+
 def _hook_failure(what: str, exc: BaseException) -> None:
     print(f"[tui_gateway] {what} failed: {type(exc).__name__}: {exc}", file=sys.stderr)
 
@@ -638,6 +656,8 @@ def _complete_turn_payload(session: dict, st: _TurnRun, status_note: str | None,
         except Exception:
             _error_surface = None
     raw, status, last_reasoning = _turn_outcome(result, _error_surface)
+    if _is_bot_mode_session(session):
+        raw = _bot_mode_delivery_text(raw, successful=status == "complete")
     payload = {"text": raw, "usage": _get_usage(agent), "status": status}
     if last_reasoning:
         payload["reasoning"] = last_reasoning