diff --git a/runtime/application/gateway/inbound_service.py b/runtime/application/gateway/inbound_service.py
index 66477953..4be5ce81 100644
--- a/runtime/application/gateway/inbound_service.py
+++ b/runtime/application/gateway/inbound_service.py
@@ -473,6 +473,7 @@ def _channel_attachments_for_gateway(raw: list[dict[str, Any]]) -> list[dict[str
     from pathlib import Path
 
     from svc.files.attachment_assets import AttachmentAssetStore
+    from svc.files.file_attachments import expand_attachment_ref, process_file_data
 
     out: list[dict[str, Any]] = []
     ast = AttachmentAssetStore()
@@ -481,8 +482,7 @@ def _channel_attachments_for_gateway(raw: list[dict[str, Any]]) -> list[dict[str
             continue
         aid = str(a.get("attachment_id") or a.get("attachmentId") or "").strip().lower()
         if aid:
-            t = str(a.get("type") or "").strip().lower() or "binary_ref"
-            out.append({"type": t, "attachment_id": aid})
+            out.extend(expand_attachment_ref(a))
             continue
         lp = str(a.get("local_path") or a.get("media_path") or "").strip()
         if not lp:
@@ -495,7 +495,15 @@ def _channel_attachments_for_gateway(raw: list[dict[str, Any]]) -> list[dict[str
         if not mime:
             mime = "application/octet-stream"
         try:
-            meta = ast.save_bytes(p.read_bytes(), filename=p.name, mime=mime)
+            data = p.read_bytes()
+        except Exception:
+            continue
+        got = process_file_data(p.name, data)
+        if got:
+            out.extend(got)
+            continue
+        try:
+            meta = ast.save_bytes(data, filename=p.name, mime=mime)
         except Exception:
             continue
         if kind == "image" or mime.startswith("image/"):
@@ -503,7 +511,7 @@ def _channel_attachments_for_gateway(raw: list[dict[str, Any]]) -> list[dict[str
         elif kind == "video" or mime.startswith("video/"):
             out.append({"type": "video_ref", "attachment_id": meta.attachment_id})
         else:
-            out.append({"type": "binary_ref", "attachment_id": meta.attachment_id})
+            out.append({"type": "binary_ref", "attachment_id": meta.attachment_id, "name": meta.name, "mime": meta.mime})
     return out
 
 
@@ -548,10 +556,16 @@ def _rows_since_last_user_message(rows: list[Any]) -> list[Any]:
     return list(rows[last_user_idx + 1 :])
 
 
+_CHANNEL_DELIVERABLE_ATTACHMENT_TYPES = frozenset(
+    {"image_ref", "video_ref", "image", "input_image", "image_url"}
+)
+
+
 def _collect_recent_tool_attachments(*, store: Any, session_id: str) -> list[dict[str, Any]]:
     """Fallback for channel delivery: reuse tool media produced during the current user turn only.
 
     Avoids re-sending images from earlier conversation turns when the latest assistant row has no attachments.
+    Only visual outbound media is eligible — not text_ref/binary_ref from read/query tools.
     """
     sid = str(session_id or "").strip()
     if not sid:
@@ -569,15 +583,16 @@ def _collect_recent_tool_attachments(*, store: Any, session_id: str) -> list[dic
         if not atts:
             continue
         ok = False
+        deliverable: list[dict[str, Any]] = []
         for a in atts:
             if not isinstance(a, dict):
                 continue
             t = str(a.get("type") or "").strip().lower()
-            if t in {"image_ref", "video_ref", "binary_ref", "text_ref", "image", "input_image", "image_url"}:
+            if t in _CHANNEL_DELIVERABLE_ATTACHMENT_TYPES:
                 ok = True
-                break
+                deliverable.append(a)
         if ok:
-            return atts
+            return deliverable
     return []
 
 
diff --git a/runtime/chat/agent_messages.py b/runtime/chat/agent_messages.py
index a0c9e6dc..f3ba61fa 100644
--- a/runtime/chat/agent_messages.py
+++ b/runtime/chat/agent_messages.py
@@ -17,7 +17,8 @@ from svc.llm.chat_models import _normalize_image_b64_payload, gemini_openai_comp
 from runtime.chat.media_redact import redact_embedded_image_blobs
 from runtime.chat.tool_runtime import tool_llm_message_max_chars, truncate_tool_result_for_llm_messages
 from runtime.prompt_templates import render_prompt
-from svc.files.attachment_assets import attachment_id_to_data_url
+from svc.files.attachment_assets import attachment_id_to_data_url, AttachmentAssetStore
+from svc.files.file_attachments import expand_attachment_ref
 from runtime.relay_pointer import parse_pointer_uri
 
 logger = logging.getLogger(__name__)
@@ -316,11 +317,24 @@ def build_llm_messages(
                 except Exception:
                     attachments = []
 
+            expand_user_image_for_model = bool(i == last_user_msg_idx)
+            if expand_user_image_for_model:
+                expanded_atts: list[dict[str, Any]] = []
+                for att in attachments or []:
+                    if not isinstance(att, dict):
+                        continue
+                    if str(att.get("type") or "").strip().lower() == "binary_ref":
+                        subs = expand_attachment_ref(att)
+                        if subs and any(str(s.get("type") or "") != "binary_ref" for s in subs):
+                            expanded_atts.extend(subs)
+                            continue
+                    expanded_atts.append(att)
+                attachments = expanded_atts
+
             for att in attachments or []:
                 if not isinstance(att, dict):
                     continue
                 att_type = att.get("type")
-                expand_user_image_for_model = bool(i == last_user_msg_idx)
                 if att_type in ("image", "input_image"):
                     if expand_user_image_for_model:
                         b64 = _normalize_image_b64_payload(att.get("image_base64") or att.get("data"))
@@ -459,6 +473,29 @@ def build_llm_messages(
                         meta_line += f"\n- bytes: {sz}"
                     meta_line += "\n- tools: query_video_attachment"
                     content_list.append({"type": "text", "text": meta_line})
+                elif att_type == "binary_ref":
+                    aid = str(att.get("attachment_id") or "").strip()
+                    name = str(att.get("name") or "file")
+                    mime = str(att.get("mime") or "application/octet-stream")
+                    sz = att.get("bytes")
+                    if aid and (name == "file" or not mime or mime == "application/octet-stream"):
+                        try:
+                            meta = AttachmentAssetStore().get_meta(aid)
+                            if meta:
+                                if name == "file":
+                                    name = str(meta.name or name)
+                                if not mime or mime == "application/octet-stream":
+                                    mime = str(meta.mime or mime)
+                                if sz is None:
+                                    sz = meta.bytes
+                        except Exception:
+                            pass
+                    meta_line = f"[BinaryAttachment]\n- name: {name}\n- mime: {mime}\n- attachment_id: {aid}"
+                    if sz:
+                        meta_line += f"\n- bytes: {sz}"
+                    meta_line += "\n- tools: attachment_local_url"
+                    meta_line += "\n- note: user uploaded a file; resolve or analyze it via attachment_id."
+                    content_list.append({"type": "text", "text": meta_line})
                 elif att_type == "relay_pointer":
                     p_uri = str(att.get("pointer_uri") or "").strip()
                     if not p_uri:
diff --git a/svc/files/file_attachments.py b/svc/files/file_attachments.py
index f8831062..625202cd 100644
--- a/svc/files/file_attachments.py
+++ b/svc/files/file_attachments.py
@@ -373,6 +373,47 @@ def process_zip(zip_data: bytes, *, _depth: int = 0) -> list[dict[str, Any]]:
     )
 
 
+def expand_attachment_ref(
+    att: dict[str, Any],
+    *,
+    data: bytes | None = None,
+    name: str | None = None,
+) -> list[dict[str, Any]]:
+    """Expand ``binary_ref`` (or raw bytes) into parsed attachment dicts for the agent."""
+    if not isinstance(att, dict):
+        return []
+    t = str(att.get("type") or "").strip().lower()
+    if t and t not in {"binary_ref"}:
+        return [att]
+    aid = str(att.get("attachment_id") or att.get("attachmentId") or "").strip().lower()
+    meta = None
+    if data is None and aid:
+        blob, meta = AttachmentAssetStore().load_bytes(aid)
+        if not blob:
+            return [att] if t == "binary_ref" else []
+        data = blob
+        name = name or str(getattr(meta, "name", "") or "file")
+    if data is None:
+        return [att] if t == "binary_ref" else []
+    fname = str(name or att.get("name") or getattr(meta, "name", "") or "file")
+    got = process_file_data(fname, data)
+    if got:
+        return got
+    if aid:
+        if meta is None:
+            meta = AttachmentAssetStore().get_meta(aid)
+        return [
+            {
+                "type": "binary_ref",
+                "attachment_id": aid,
+                "name": fname,
+                "mime": str(att.get("mime") or getattr(meta, "mime", "") or "application/octet-stream"),
+                "bytes": att.get("bytes") if att.get("bytes") is not None else getattr(meta, "bytes", None),
+            }
+        ]
+    return []
+
+
 def process_file_data(name: str, data: bytes, *, _zip_depth: int = 0) -> list[dict[str, Any]]:
     ext = name.split(".")[-1].lower() if "." in name else ""
     attachments: list[dict[str, Any]] = []
@@ -773,4 +814,4 @@ def process_file_data(name: str, data: bytes, *, _zip_depth: int = 0) -> list[di
     return attachments
 
 
-__all__ = ["process_zip", "process_file_data", "clear_attachment_limits_cache"]
+__all__ = ["process_zip", "process_file_data", "expand_attachment_ref", "clear_attachment_limits_cache"]
diff --git a/tests/test_binary_ref_attachments.py b/tests/test_binary_ref_attachments.py
new file mode 100644
index 00000000..5239a10d
--- /dev/null
+++ b/tests/test_binary_ref_attachments.py
@@ -0,0 +1,98 @@
+from __future__ import annotations
+
+from types import SimpleNamespace
+
+import pytest
+
+from runtime.application.gateway.inbound_service import _channel_attachments_for_gateway
+from runtime.chat.agent_messages import build_llm_messages
+from svc.files.attachment_assets import AttachmentAssetStore
+from svc.files.file_attachments import expand_attachment_ref
+from svc.llm.chat_models import RuleBasedChatModel
+
+
+@pytest.fixture
+def att_store(tmp_path, monkeypatch):
+    store = AttachmentAssetStore(root_dir=tmp_path / "att")
+
+    def _factory(root_dir=None):
+        if root_dir is None:
+            return store
+        return AttachmentAssetStore(root_dir=root_dir)
+
+    monkeypatch.setattr("svc.files.file_attachments.AttachmentAssetStore", _factory)
+    monkeypatch.setattr("runtime.chat.agent_messages.AttachmentAssetStore", _factory)
+    return store
+
+
+def _msg_text(message: dict) -> str:
+    content = message.get("content")
+    if isinstance(content, list):
+        return "\n".join(str(x.get("text") or "") for x in content if isinstance(x, dict))
+    return str(content or "")
+
+
+def test_expand_attachment_ref_large_txt_becomes_text_ref(att_store) -> None:
+    text = ("line\n" * 5000).strip()
+    data = text.encode("utf-8")
+    meta = att_store.save_bytes(data, filename="sites.txt", mime="text/plain")
+    got = expand_attachment_ref({"type": "binary_ref", "attachment_id": meta.attachment_id})
+    types = {str(x.get("type") or "") for x in got}
+    assert "text_ref" in types
+    assert "text" in types
+
+
+def test_channel_attachments_for_gateway_parses_local_txt(tmp_path) -> None:
+    p = tmp_path / "Site_List.txt"
+    p.write_text("a\nb\nc\n", encoding="utf-8")
+    got = _channel_attachments_for_gateway([{"local_path": str(p), "kind": "document", "mime": "text/plain"}])
+    assert got
+    assert any(str(x.get("type") or "") == "text" for x in got)
+
+
+def test_build_llm_messages_binary_ref_meta_for_historical_turn(att_store) -> None:
+    data = b"hello attachment"
+    meta = att_store.save_bytes(data, filename="note.txt", mime="text/plain")
+    rows = [
+        SimpleNamespace(
+            role="user",
+            event_type="user_text",
+            content="first",
+            attachments=[{"type": "binary_ref", "attachment_id": meta.attachment_id}],
+            tool_calls=None,
+            turn_uuid="t1",
+        ),
+        SimpleNamespace(
+            role="user",
+            event_type="user_text",
+            content="second",
+            attachments=None,
+            tool_calls=None,
+            turn_uuid="t2",
+        ),
+    ]
+    msgs = build_llm_messages(store_messages=rows, system_prompt="s", model=RuleBasedChatModel(), lang="zh")
+    first_user = next(m for m in msgs if m.get("role") == "user" and "first" in _msg_text(m))
+    content = _msg_text(first_user)
+    assert "BinaryAttachment" in content
+    assert meta.attachment_id in content
+
+
+def test_build_llm_messages_binary_ref_expands_on_last_turn(att_store) -> None:
+    text = ("row\n" * 4000).strip()
+    data = text.encode("utf-8")
+    meta = att_store.save_bytes(data, filename="Site_List.txt", mime="text/plain")
+    rows = [
+        SimpleNamespace(
+            role="user",
+            event_type="user_text",
+            content="帮看一下有多少数据",
+            attachments=[{"type": "binary_ref", "attachment_id": meta.attachment_id}],
+            tool_calls=None,
+            turn_uuid="t1",
+        ),
+    ]
+    msgs = build_llm_messages(store_messages=rows, system_prompt="s", model=RuleBasedChatModel(), lang="zh")
+    user = msgs[-1]
+    content = _msg_text(user)
+    assert "LongTextAttachment" in content or "text_id" in content
diff --git a/tests/test_inbound_service_reply_suppress.py b/tests/test_inbound_service_reply_suppress.py
index 1bf0be28..dbed3938 100644
--- a/tests/test_inbound_service_reply_suppress.py
+++ b/tests/test_inbound_service_reply_suppress.py
@@ -174,6 +174,20 @@ def test_collect_recent_tool_attachments_ignores_media_from_prior_turn() -> None
     assert out == []
 
 
+def test_collect_recent_tool_attachments_ignores_text_ref_from_lookup_tools() -> None:
+    rows = [
+        _Row(role="user", content="analyze file", attachments=None),
+        _Row(
+            role="tool",
+            content="{}",
+            attachments='[{"type":"text_ref","attachment_id":"user-upload","name":"Site_List.txt","mime":"text/plain"}]',
+        ),
+        _Row(role="assistant", content="15,687 rows", attachments=None),
+    ]
+    out = _collect_recent_tool_attachments(store=_FakeStore(rows), session_id="s1")
+    assert out == []
+
+
 def test_maybe_add_media_path_for_wechat_reply_sets_media_path(monkeypatch) -> None:
     # Avoid touching disk: stub AttachmentAssetStore.get_local_path.
     from pathlib import Path