diff --git a/gateway/run_busy.py b/gateway/run_busy.py
index 54d613efe0..d9d0440b7e 100644
--- a/gateway/run_busy.py
+++ b/gateway/run_busy.py
@@ -353,6 +353,19 @@ class GatewayBusySessionMixin:
             "source_message_id": source.message_id,
         }
         origin = {key: value for key, value in origin.items() if value not in (None, "")}
+        from gateway.run import _load_gateway_config
+        from gateway.session import _hash_chat_id, _hash_id, _hash_sender_id, _should_redact_pii
+
+        redact_pii = bool((_load_gateway_config().get("privacy") or {}).get("redact_pii", False))
+        if _should_redact_pii(source.platform, redact_pii):
+            # Only the model-facing copy changes; event/source remain valid routing state.
+            hashers = {
+                "user_id": _hash_sender_id, "user_id_alt": _hash_sender_id,
+                "chat_id": _hash_chat_id, "chat_id_alt": _hash_chat_id,
+                "parent_chat_id": _hash_chat_id,
+            }
+            origin = {key: (value if key in ("platform", "chat_type") else
+                            hashers.get(key, _hash_id)(value)) for key, value in origin.items()}
         # JSON preserves identifiers exactly (including colons/whitespace) instead of
         # normalizing them into another destination. Escape marker delimiters too.
         encoded = json.dumps(origin, ensure_ascii=True).replace("[", "\\u005b").replace("]", "\\u005d")
diff --git a/gateway/session.py b/gateway/session.py
index 17f3587122..d102e59388 100644
--- a/gateway/session.py
+++ b/gateway/session.py
@@ -189,6 +189,18 @@ _PII_SAFE_PLATFORMS = frozenset({
 })
 
 
+def _should_redact_pii(platform: Platform, enabled: bool) -> bool:
+    """Keep model-visible identifiers usable on platforms requiring raw mentions."""
+    if not enabled or platform in _PII_SAFE_PLATFORMS:
+        return enabled
+    try:
+        from gateway.platform_registry import platform_registry
+        entry = platform_registry.get(platform.value)
+        return bool(entry and entry.pii_safe)
+    except Exception:
+        return False
+
+
 def _slack_tools_loaded() -> bool:
     """True iff the agent will actually have Slack tools this session.
 
@@ -357,13 +369,7 @@ def build_session_context_prompt(context: SessionContext, *, redact_pii: bool =
     user/chat IDs become deterministic hashes for the LLM only; routing keeps the originals.
     """
     src = context.source
-    if redact_pii and src.platform not in _PII_SAFE_PLATFORMS:
-        try:
-            from gateway.platform_registry import platform_registry
-            entry = platform_registry.get(src.platform.value)
-            redact_pii = bool(entry and entry.pii_safe)
-        except Exception:
-            redact_pii = False
+    redact_pii = _should_redact_pii(src.platform, redact_pii)
 
     def _chat_label(chat_id: str) -> str:
         return _hash_chat_id(chat_id) if redact_pii else chat_id
diff --git a/tests/gateway/test_busy_steer_origin.py b/tests/gateway/test_busy_steer_origin.py
index 8705fe6ff4..403e92396c 100644
--- a/tests/gateway/test_busy_steer_origin.py
+++ b/tests/gateway/test_busy_steer_origin.py
@@ -12,14 +12,24 @@ from gateway.session import SessionSource
 
 @pytest.mark.asyncio
 @pytest.mark.parametrize("route", ["explicit", "priority", "normal", "redirect", "priority_redirect"])
-async def test_busy_injection_preserves_original_routing_fields(route):
+@pytest.mark.parametrize("platform", [Platform.TELEGRAM, Platform.SIGNAL, Platform.WHATSAPP, Platform.DISCORD])
+@pytest.mark.parametrize("redact_pii", [False, True])
+async def test_busy_injection_preserves_original_routing_fields(route, platform, redact_pii, tmp_path, monkeypatch):
+    from dataclasses import asdict
+    from gateway.session import _hash_chat_id, _hash_id, _hash_sender_id
+
+    monkeypatch.setattr("gateway.run._hermes_home", tmp_path)
+    (tmp_path / "config.yaml").write_text(
+        f"privacy:\n  redact_pii: {str(redact_pii).lower()}\n", encoding="utf-8",
+    )
     runner = GatewayRunner(config=GatewayConfig())
     source = SessionSource(
-        platform=Platform.TELEGRAM, chat_id="chat", thread_id="thread", user_id="user",
+        platform=platform, chat_id="+15551230001", thread_id="thread", user_id="+15551230002",
         chat_type="group", scope_id="scope", profile="profile", parent_chat_id="parent",
         chat_id_alt="chat-alt", user_id_alt="user-alt", prospective_thread_id="future-thread",
         message_id="source-message",
     )
+    original_source = asdict(source)
     event = MessageEvent(text="/steer request" if route == "explicit" else "request", source=source, message_id="message")
 
     class Receiver:
@@ -44,12 +54,21 @@ async def test_busy_injection_preserves_original_routing_fields(route):
         await runner._resolve_busy_steer_or_redirect(event, "key", "interrupt" if route == "redirect" else "steer", receiver)
     assert receiver.payload.endswith("\n\nrequest")
     origin = json.loads(receiver.payload.splitlines()[1])
-    assert {key: origin[key] for key in ("platform", "chat_id", "thread_id", "user_id", "message_id")} == {
-        "platform": "telegram", "chat_id": "chat", "thread_id": "thread", "user_id": "user", "message_id": "message",
-    }
-    for field in ("chat_type", "scope_id", "profile", "parent_chat_id", "chat_id_alt", "user_id_alt", "prospective_thread_id"):
-        assert origin[field] == getattr(source, field)
-    assert origin["source_message_id"] == source.message_id
+    expected = {key: original_source[key] for key in (
+        "chat_id", "thread_id", "user_id", "chat_type", "scope_id", "profile",
+        "parent_chat_id", "chat_id_alt", "user_id_alt", "prospective_thread_id",
+    )}
+    expected.update(platform=platform.value, message_id=event.message_id, source_message_id=source.message_id)
+    if redact_pii and platform != Platform.DISCORD:
+        for key, value in expected.items():
+            if key in ("platform", "chat_type"):
+                continue
+            hasher = (_hash_sender_id if key in ("user_id", "user_id_alt") else
+                      _hash_chat_id if key in ("chat_id", "chat_id_alt", "parent_chat_id") else _hash_id)
+            expected[key] = hasher(value)
+            assert origin[key] != value
+    assert origin == expected
+    assert asdict(source) == original_source
     assert event.text == ("/steer request" if route == "explicit" else "request")
 
 
diff --git a/website/docs/user-guide/messaging/index.md b/website/docs/user-guide/messaging/index.md
index 4cfe6f58ea..b792b962aa 100644
--- a/website/docs/user-guide/messaging/index.md
+++ b/website/docs/user-guide/messaging/index.md
@@ -400,7 +400,7 @@ By default, messaging a busy agent redirects its active turn (a running foregrou
 - `queue` — follow-up messages wait and run as the next turn after the current task finishes.
 - `steer` — follow-up messages are injected into the current run via `/steer`, arriving at the agent after the next tool call. No interrupt, no new turn. Falls back to `queue` behavior if the agent hasn't started yet.
 
-Gateway steers (including explicit `/steer`) and active-turn redirects carry the requesting event's available platform, chat, thread, sender, message, profile, and scope identifiers as per-message JSON context. This preserves the original identifiers without changing the session's system prompt or choosing a fallback reply destination. The context is routing data, not authorization or a guarantee of automatic delivery.
+Gateway steers (including explicit `/steer`) and active-turn redirects carry the requesting event's available platform, chat, thread, sender, message, profile, and scope identifiers as per-message JSON context. With `privacy.redact_pii: true`, identifiers in this model-visible context are hashed on supported platforms, including alternate and parent identifiers; the original event identifiers remain internal for routing. Otherwise identifiers are preserved exactly. Neither mode changes the session's system prompt or chooses a fallback reply destination. The context is routing data, not authorization or a guarantee of automatic delivery.
 
 ```yaml
 display: