diff --git a/yunke-server/app/scraper/whatsapp.py b/yunke-server/app/scraper/whatsapp.py
index d2d3a0b..5319b69 100644
--- a/yunke-server/app/scraper/whatsapp.py
+++ b/yunke-server/app/scraper/whatsapp.py
@@ -203,9 +203,26 @@ def _parse_wa_friend_rows(resp: Any) -> list[dict[str, Any]]:
     return rows if isinstance(rows, list) else []
 
 
-def _build_wa_friend_body(page_num: int, page_size: int) -> dict[str, Any]:
-    """Build the ``businessFriendList`` request body for a given page."""
-    return {"pageNum": page_num, "pageSize": page_size}
+def _build_wa_friend_body(
+    page_num: int, page_size: int, *, department_id: str = ""
+) -> dict[str, Any]:
+    """Build the ``businessFriendList`` request body for a given page.
+
+    Live capture: ``{"searchInfo":"","friendSearchInfo":"","page":1,
+    "pageSize":10,"departmentId":"<root>","type":"0"}``. Note this endpoint
+    uses ``page`` (NOT ``pageNum`` like businessSalesList) and REQUIRES
+    ``departmentId`` (the company-root dept id) + ``type`` or it returns empty.
+    """
+    body: dict[str, Any] = {
+        "searchInfo": "",
+        "friendSearchInfo": "",
+        "page": page_num,
+        "pageSize": page_size,
+        "type": "0",
+    }
+    if department_id:
+        body["departmentId"] = department_id
+    return body
 
 
 def _normalize_whatsapp_friend(record: dict[str, Any]) -> dict[str, Any]:
@@ -246,6 +263,7 @@ def _normalize_whatsapp_friend(record: dict[str, Any]) -> dict[str, Any]:
 async def scrape_whatsapp_friends(
     client: YunkeClient,
     *,
+    department_id: str = "",
     page_size: int = 50,
 ) -> AsyncIterator[dict[str, Any]]:
     """Yield normalized WhatsApp contact records from ``businessFriendList``.
@@ -270,6 +288,7 @@ async def scrape_whatsapp_friends(
         parse_total=_parse_wa_friend_total,
         parse_rows=_parse_wa_friend_rows,
         build_body=_build_wa_friend_body,
+        department_id=department_id,
     ):
         yield _normalize_whatsapp_friend(record)
 
diff --git a/yunke-server/scripts/seed_whatsapp.py b/yunke-server/scripts/seed_whatsapp.py
new file mode 100644
index 0000000..f3d2b45
--- /dev/null
+++ b/yunke-server/scripts/seed_whatsapp.py
@@ -0,0 +1,58 @@
+"""Seed a slice of WhatsApp friends + one conversation's messages into smoke.db."""
+import asyncio
+import time
+
+from sqlalchemy.ext.asyncio import async_sessionmaker, create_async_engine
+
+from app.db import models  # noqa: F401
+from app.scraper.wechat import scrape_departments
+from app.scraper.whatsapp import scrape_whatsapp_friends, scrape_whatsapp_messages
+from app.storage.repos import upsert_customer, upsert_messages
+from scripts.smoke_wechat import _push_settings_into_environ, build_client_from_env
+
+# A known active WhatsApp conversation (Pasha-hesucar <-> Алекс).
+UID = "15638182659@s.whatsapp.net"
+FRIEND_UID = "375292581799@s.whatsapp.net"
+
+
+async def _root_department_id(client) -> str | None:
+    async for d in scrape_departments(client):
+        if not d.get("parent_id"):
+            return d.get("dept_id")
+    return None
+
+
+async def main() -> None:
+    _push_settings_into_environ()
+    client = build_client_from_env()
+    engine = create_async_engine("sqlite+aiosqlite:///./smoke.db")
+    sm = async_sessionmaker(engine, expire_on_commit=False)
+
+    root_dept = await _root_department_id(client)
+    friends = []
+    async for rec in scrape_whatsapp_friends(
+        client, department_id=root_dept or "", page_size=10
+    ):
+        friends.append(rec)
+        if len(friends) >= 10:
+            break
+
+    now = int(time.time() * 1000)
+    msgs = []
+    async for m in scrape_whatsapp_messages(client, UID, FRIEND_UID, now - 60 * 86_400_000, now):
+        msgs.append(m)
+        if len(msgs) >= 40:
+            break
+
+    async with sm() as session:
+        for rec in friends:
+            await upsert_customer(session, rec)
+        nmsg = await upsert_messages(session, msgs)
+        await session.commit()
+    print(f"upserted {len(friends)} whatsapp friends, {nmsg} whatsapp messages")
+    await client.aclose()
+    await engine.dispose()
+
+
+if __name__ == "__main__":
+    asyncio.run(main())
diff --git a/yunke-server/tests/test_scrape_whatsapp_friends.py b/yunke-server/tests/test_scrape_whatsapp_friends.py
index ac9d810..f8d4a1b 100644
--- a/yunke-server/tests/test_scrape_whatsapp_friends.py
+++ b/yunke-server/tests/test_scrape_whatsapp_friends.py
@@ -130,7 +130,12 @@ async def test_scrape_whatsapp_friends_sends_pagination_body():
 
     client = _primed_client()
     try:
-        results = [r async for r in scrape_whatsapp_friends(client, page_size=1)]
+        results = [
+            r
+            async for r in scrape_whatsapp_friends(
+                client, department_id="ROOT_DEPT", page_size=1
+            )
+        ]
     finally:
         await client.aclose()
 
@@ -138,11 +143,14 @@ async def test_scrape_whatsapp_friends_sends_pagination_body():
     assert route.call_count == 2
 
     body1 = _json.loads(route.calls[0].request.content.decode())
-    assert body1["pageNum"] == 1
+    # businessFriendList uses `page` (not pageNum) + departmentId + type.
+    assert body1["page"] == 1
     assert body1["pageSize"] == 1
+    assert body1["departmentId"] == "ROOT_DEPT"
+    assert body1["type"] == "0"
 
     body2 = _json.loads(route.calls[1].request.content.decode())
-    assert body2["pageNum"] == 2
+    assert body2["page"] == 2
     assert body2["pageSize"] == 1