handoff fixes

backend/app/routers/agent_handoff.py

@@ -264,13 +264,23 @@ async def get_handoff_conversation(
         sender_address = (message.get("sender") or {}).get("address", "").lower()
         role = "human" if sender_address == human_email else "agent"
         event_at = row.get("event_at") or message.get("received_at") or message.get("sent_at") or message["created_at"]
+        raw_body = message.get("raw_body")
+        new_reply_content = message.get("new_reply_content")
+        display_body = new_reply_content or message.get("body_text", "")
         messages.append(
             HandoffMessageRead(
                 id=str(message["_id"]),
                 role=role,
                 subject=message.get("subject", ""),
-                snippet=message.get("snippet", ""),
+                snippet=message.get("snippet", "") or display_body[:240],
-                body_text=message.get("body_text", ""),
+                body_text=display_body,
+                new_reply_content=new_reply_content,
+                raw_body=raw_body,
+                has_quoted_text=bool(
+                    raw_body
+                    and new_reply_content
+                    and raw_body.strip() != new_reply_content.strip()
+                ),
                 event_at=event_at,
             )
         )

backend/app/schemas.py

@@ -314,6 +314,9 @@ class HandoffMessageRead(BaseModel):
     subject: str
     snippet: str
     body_text: str
+    new_reply_content: str | None = None
+    raw_body: str | None = None
+    has_quoted_text: bool = False
     event_at: datetime
 
 

backend/app/services/handoff_email_templates.py

@@ -0,0 +1,198 @@
+from html import escape
+
+DEBUG_REASON_MARKERS = (
+    "step passes",
+    "classifier",
+    "rule evaluation",
+    "no handoff instructions were set",
+)
+
+
+def _clean_external_subject(subject: str) -> str:
+    value = (subject or "(No subject)").strip()
+    for prefix in ("Re: ", "RE: ", "re: "):
+        if value.startswith(prefix):
+            value = value[len(prefix) :].strip()
+    for prefix in ("Human Handoff · ", "Human Handoff: "):
+        if value.lower().startswith(prefix.lower()):
+            value = value[len(prefix) :].strip()
+    return value or "(No subject)"
+
+
+def handoff_email_subject(external_subject: str) -> str:
+    return f"Human Handoff · {_clean_external_subject(external_subject)}"
+
+
+def external_reply_subject(external_subject: str) -> str:
+    cleaned = _clean_external_subject(external_subject)
+    return f"Re: {cleaned}"
+
+
+def format_reason_for_human(reason: str | None, *, is_update: bool = False) -> str | None:
+    if is_update:
+        return None
+    if not reason or not reason.strip():
+        return None
+    lower = reason.strip().lower()
+    if any(marker in lower for marker in DEBUG_REASON_MARKERS):
+        return "This conversation matched your Human Handoff settings."
+    if lower in {
+        "matched handoff rules.",
+        "new message in the linked conversation.",
+    }:
+        return "This conversation requires human attention."
+    return reason.strip()
+
+
+def build_initial_handoff_text(
+    *,
+    external_sender: str,
+    external_subject: str,
+    external_body: str,
+    agent_email: str,
+    handoff_reason: str | None,
+) -> str:
+    reason = format_reason_for_human(handoff_reason)
+    lines = [
+        "GENTIC — HUMAN HANDOFF",
+        "",
+        "This conversation needs your attention.",
+        "",
+        f"From: {external_sender}",
+        f"Subject: {_clean_external_subject(external_subject)}",
+        "",
+        "LATEST MESSAGE",
+        "",
+        external_body.strip(),
+        "",
+    ]
+    if reason:
+        lines.extend(["WHY YOU'RE RECEIVING THIS", "", reason, ""])
+    lines.extend(
+        [
+            "REPLY NORMALLY",
+            "",
+            f"Reply to this email and Gentic will send only your new reply to the "
+            f"original sender through {agent_email}.",
+            "",
+            "This private handoff conversation and quoted history will not be shared "
+            "with the sender.",
+            "",
+            "—",
+            "Gentic Human Handoff",
+            "Private Agent ↔ Human conversation",
+        ]
+    )
+    return "\n".join(lines)
+
+
+def build_initial_handoff_html(
+    *,
+    external_sender: str,
+    external_subject: str,
+    external_body: str,
+    agent_email: str,
+    handoff_reason: str | None,
+) -> str:
+    reason = format_reason_for_human(handoff_reason)
+    reason_block = ""
+    if reason:
+        reason_block = f"""
+          <tr><td style="padding:18px 24px 0;">
+            <p style="margin:0 0 8px;font-size:11px;font-weight:600;letter-spacing:.05em;text-transform:uppercase;color:#8A8695;">Why you&apos;re receiving this</p>
+            <p style="margin:0;font-size:13px;line-height:1.55;color:#4A4652;">{escape(reason)}</p>
+          </td></tr>"""
+
+    return f"""<!DOCTYPE html>
+<html><body style="margin:0;padding:0;background:#F5F4F2;">
+  <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background:#F5F4F2;padding:24px 12px;">
+    <tr><td align="center">
+      <table role="presentation" width="600" cellpadding="0" cellspacing="0" style="width:100%;max-width:600px;background:#FFFFFF;border:1px solid #E8E5EA;border-radius:12px;overflow:hidden;">
+        <tr><td style="padding:24px 24px 8px;">
+          <p style="margin:0 0 4px;font-size:12px;font-weight:600;color:#7357F6;">✦ Gentic</p>
+          <h1 style="margin:0 0 8px;font-size:20px;font-weight:700;color:#171424;">Human Handoff</h1>
+          <p style="margin:0;font-size:13px;line-height:1.5;color:#77758A;">This conversation needs your attention.</p>
+        </td></tr>
+        <tr><td style="padding:8px 24px 0;">
+          <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background:#FAF9FB;border:1px solid #ECE9EF;border-radius:8px;">
+            <tr><td style="padding:14px;">
+              <p style="margin:0 0 10px;font-size:10px;font-weight:600;letter-spacing:.05em;text-transform:uppercase;color:#8A8695;">From</p>
+              <p style="margin:0 0 14px;font-size:13px;font-weight:500;color:#292536;">{escape(external_sender)}</p>
+              <p style="margin:0 0 10px;font-size:10px;font-weight:600;letter-spacing:.05em;text-transform:uppercase;color:#8A8695;">Subject</p>
+              <p style="margin:0;font-size:13px;font-weight:500;color:#292536;">{escape(_clean_external_subject(external_subject))}</p>
+            </td></tr>
+          </table>
+        </td></tr>
+        <tr><td style="padding:18px 24px 0;">
+          <p style="margin:0 0 8px;font-size:11px;font-weight:600;letter-spacing:.05em;text-transform:uppercase;color:#8A8695;">Latest message</p>
+          <div style="border-left:3px solid #7357F6;padding:4px 0 4px 14px;font-size:14px;line-height:1.55;color:#292536;white-space:pre-wrap;">{escape(external_body.strip())}</div>
+        </td></tr>
+        {reason_block}
+        <tr><td style="padding:18px 24px 24px;">
+          <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background:#F7F5FF;border:1px solid #E5DFFF;border-radius:8px;">
+            <tr><td style="padding:14px;">
+              <p style="margin:0 0 8px;font-size:13px;font-weight:650;color:#5633CE;">↩ Reply normally</p>
+              <p style="margin:0;font-size:12px;line-height:1.5;color:#625D70;">
+                Reply to this email and Gentic will send your response to the original sender as
+                <strong>{escape(agent_email)}</strong>. Only the new text you write will be sent.
+                This handoff email and quoted history stay private.
+              </p>
+            </td></tr>
+          </table>
+        </td></tr>
+        <tr><td style="padding:0 24px 24px;text-align:center;">
+          <p style="margin:0;font-size:10px;color:#A19DAA;">Gentic Human Handoff<br>Private Agent ↔ Human conversation</p>
+        </td></tr>
+      </table>
+    </td></tr>
+  </table>
+</body></html>"""
+
+
+def build_update_handoff_text(
+    *,
+    external_sender: str,
+    external_body: str,
+    agent_email: str,
+) -> str:
+    return "\n".join(
+        [
+            "Customer replied",
+            "",
+            external_sender,
+            "",
+            external_body.strip(),
+            "",
+            f"Reply normally to respond through {agent_email}.",
+        ]
+    )
+
+
+def build_update_handoff_html(
+    *,
+    external_sender: str,
+    external_body: str,
+    agent_email: str,
+) -> str:
+    return f"""<!DOCTYPE html>
+<html><body style="margin:0;padding:0;background:#F5F4F2;">
+  <table role="presentation" width="100%" cellpadding="0" cellspacing="0" style="background:#F5F4F2;padding:24px 12px;">
+    <tr><td align="center">
+      <table role="presentation" width="600" cellpadding="0" cellspacing="0" style="width:100%;max-width:600px;background:#FFFFFF;border:1px solid #E8E5EA;border-radius:12px;">
+        <tr><td style="padding:24px;">
+          <p style="margin:0 0 8px;font-size:12px;font-weight:600;color:#7357F6;">✦ Gentic</p>
+          <h1 style="margin:0 0 16px;font-size:18px;font-weight:700;color:#171424;">Customer replied</h1>
+          <p style="margin:0 0 12px;font-size:13px;font-weight:500;color:#292536;">{escape(external_sender)}</p>
+          <div style="border-left:3px solid #7357F6;padding:4px 0 4px 14px;font-size:14px;line-height:1.55;color:#292536;white-space:pre-wrap;">{escape(external_body.strip())}</div>
+          <p style="margin:18px 0 0;font-size:12px;line-height:1.5;color:#625D70;">
+            Reply normally to respond through <strong>{escape(agent_email)}</strong>.
+          </p>
+        </td></tr>
+      </table>
+    </td></tr>
+  </table>
+</body></html>"""
+
+
+def build_relay_confirmation_text(customer_body: str) -> str:
+    return f"Sent to customer:\n\n{customer_body.strip()}"

backend/app/services/human_handoff_service.py

@@ -4,9 +4,19 @@ from datetime import datetime, timezone
 
 from bson import ObjectId
 
+from app.services.handoff_email_templates import (
+    build_initial_handoff_html,
+    build_initial_handoff_text,
+    build_relay_confirmation_text,
+    build_update_handoff_html,
+    build_update_handoff_text,
+    external_reply_subject,
+    handoff_email_subject,
+)
 from app.services.handoff_evaluator import evaluate_handoff
 from app.services.mail_sender import deliver_email
-from app.services.message_ids import build_references_header, normalize_message_id, parse_message_id_list
+from app.services.message_ids import normalize_message_id, parse_message_id_list
+from app.services.reply_extractor import extract_new_reply_content, validate_external_reply_body
 from app.services.thread_service import (
     attach_message_to_thread,
     message_event_at,
@@ -42,36 +52,8 @@ def _snippet(text: str, limit: int = 240) -> str:
     return re.sub(r"\s+", " ", (text or "")).strip()[:limit]
 
 
-def _handoff_subject(external_subject: str) -> str:
+def _handoff_reply_subject(external_subject: str) -> str:
-    subject = (external_subject or "(No subject)").strip()
+    return f"Re: {handoff_email_subject(external_subject)}"
-    if subject.lower().startswith("human handoff:"):
-        return subject
-    return f"Human Handoff: {subject}"
-
-
-def _build_handoff_body(
-    *,
-    external_sender: str,
-    external_subject: str,
-    external_body: str,
-    handoff_reason: str,
-    agent_email: str,
-) -> str:
-    return (
-        "Human Handoff\n\n"
-        "A conversation needs your attention.\n\n"
-        f"From\n{external_sender}\n\n"
-        f"Subject\n{external_subject}\n\n"
-        "Latest message\n\n"
-        f"\"{external_body.strip()}\"\n\n"
-        "Why this was handed off\n\n"
-        f"{handoff_reason}\n\n"
-        "────────────────────────────────────────\n\n"
-        f"Reply to this email to respond to the original sender through {agent_email}.\n\n"
-        "Your reply will be sent to the customer.\n\n"
-        "────────────────────────────────────────\n\n"
-        "Gentic Human Handoff"
-    )
 
 
 async def create_empty_handoff_thread(
@@ -114,6 +96,47 @@ async def _record_message_link(
     )
 
 
+async def _latest_external_customer_message(
+    database,
+    account_id: str,
+    external_thread_id: ObjectId,
+    customer_address: str,
+) -> dict | None:
+    customer = customer_address.lower()
+    pipeline = [
+        {
+            "$match": {
+                "account_id": account_id,
+                "thread_id": external_thread_id,
+                "message_scope": MESSAGE_SCOPE_EXTERNAL,
+                "deletion_state": {"$in": [None, ""]},
+            }
+        },
+        {"$sort": {"event_at": -1, "_id": -1}},
+        {
+            "$lookup": {
+                "from": "messages",
+                "localField": "message_id",
+                "foreignField": "_id",
+                "as": "message",
+            }
+        },
+        {"$unwind": "$message"},
+        {
+            "$match": {
+                "$or": [
+                    {"message.direction": "inbound"},
+                    {"message.sender.address": customer},
+                ]
+            }
+        },
+        {"$limit": 1},
+    ]
+    cursor = await database.mailbox_entries.aggregate(pipeline)
+    rows = [row async for row in cursor]
+    return rows[0]["message"] if rows else None
+
+
 async def _latest_external_message(database, account_id: str, external_thread_id: ObjectId) -> dict | None:
     pipeline = [
         {
@@ -250,8 +273,12 @@ async def store_handoff_message(
     link_relationship: str | None = None,
     external_message_id: ObjectId | None = None,
     event_at: datetime | None = None,
+    raw_body: str | None = None,
+    new_reply_content: str | None = None,
+    body_html: str | None = None,
 ) -> dict:
     now = event_at or _now()
+    display_body = new_reply_content if new_reply_content is not None else body_text
     document = {
         "direction": direction,
         "message_scope": MESSAGE_SCOPE_HANDOFF,
@@ -259,9 +286,11 @@ async def store_handoff_message(
         "sender": sender,
         "to": recipients,
         "subject": subject,
-        "snippet": _snippet(body_text),
+        "snippet": _snippet(display_body),
-        "body_text": body_text,
+        "body_text": display_body,
-        "body_html": None,
+        "raw_body": raw_body,
+        "new_reply_content": new_reply_content,
+        "body_html": body_html,
         "attachments": [],
         "created_at": now,
         "sent_at": now if direction == "outbound" else None,
@@ -331,17 +360,21 @@ async def send_handoff_to_human(
     external_subject = external_message.get("subject", "")
     external_body = external_message.get("body_text") or external_message.get("snippet") or ""
 
+    stable_subject = handoff_email_subject(external_subject)
     if existing_handoff:
         handoff_id = existing_handoff["_id"]
         handoff_thread_id = existing_handoff["handoff_thread_id"]
         parent = await _latest_handoff_message(database, account_id, handoff_thread_id)
         threading = threading_fields_from_parent(parent) if parent else {}
-        subject = _handoff_subject(external_subject)
+        subject = _handoff_reply_subject(external_subject)
-        body = _build_handoff_body(
+        body_text = build_update_handoff_text(
+            external_sender=external_sender_text,
+            external_body=external_body,
+            agent_email=agent_email,
+        )
+        body_html = build_update_handoff_html(
             external_sender=external_sender_text,
-            external_subject=external_subject,
             external_body=external_body,
-            handoff_reason="New message in the linked conversation.",
             agent_email=agent_email,
         )
         relationship = LINK_EXTERNAL_UPDATE_RELAYED
@@ -349,11 +382,18 @@ async def send_handoff_to_human(
         handoff_thread_id = await create_empty_handoff_thread(
             database,
             account_id=account_id,
-            subject=_handoff_subject(external_subject),
+            subject=stable_subject,
         )
         threading = {}
-        subject = _handoff_subject(external_subject)
+        subject = stable_subject
-        body = _build_handoff_body(
+        body_text = build_initial_handoff_text(
+            external_sender=external_sender_text,
+            external_subject=external_subject,
+            external_body=external_body,
+            handoff_reason=handoff_reason,
+            agent_email=agent_email,
+        )
+        body_html = build_initial_handoff_html(
             external_sender=external_sender_text,
             external_subject=external_subject,
             external_body=external_body,
@@ -386,8 +426,8 @@ async def send_handoff_to_human(
         cc=[],
         bcc=[],
         subject=subject,
-        body_text=body,
+        body_text=body_text,
-        body_html=None,
+        body_html=body_html,
         domain=domain,
         in_reply_to=threading.get("in_reply_to"),
         references=threading.get("references"),
@@ -402,7 +442,8 @@ async def send_handoff_to_human(
         sender={"name": "Gentic Agent", "address": agent_email},
         recipients=[{"name": human_email.split("@")[0], "address": human_email}],
         subject=subject,
-        body_text=body,
+        body_text=body_text,
+        body_html=body_html,
         internet_message_id=internet_message_id,
         in_reply_to=threading.get("in_reply_to"),
         references=threading.get("references"),
@@ -458,6 +499,13 @@ async def process_human_reply(
     rule = await _handoff_rule_for_human(database, account_id, human_email)
     allow_replies = rule.get("allow_replies", True) if rule else True
 
+    extracted = extract_new_reply_content(
+        body_text=inbound_body,
+        body_html=inbound_parsed.get("body_html"),
+    )
+    new_reply_content = extracted["new_reply_content"].strip()
+    raw_body = extracted["raw_body"]
+
     human_message = await store_handoff_message(
         database,
         account_id=account_id,
@@ -467,7 +515,10 @@ async def process_human_reply(
         sender={"name": human_email.split("@")[0], "address": human_email},
         recipients=[{"name": "Gentic Agent", "address": agent_email}],
         subject=inbound_parsed.get("subject", ""),
-        body_text=inbound_body,
+        body_text=raw_body,
+        raw_body=raw_body,
+        new_reply_content=new_reply_content,
+        body_html=inbound_parsed.get("body_html"),
         internet_message_id=inbound_parsed.get("message_id"),
         in_reply_to=inbound_parsed.get("in_reply_to"),
         references=inbound_parsed.get("references", []),
@@ -490,21 +541,56 @@ async def process_human_reply(
         )
         return
 
+    if not new_reply_content:
+        logger.warning(
+            "handoff_reply_empty_extract handoff_id=%s account=%s",
+            handoff["_id"],
+            account_id,
+        )
+        await database.human_handoffs.update_one(
+            {"_id": handoff["_id"]},
+            {
+                "$set": {
+                    "status": HANDOFF_STATUS_HUMAN_REPLIED,
+                    "current_owner": OWNER_AGENT,
+                    "updated_at": now,
+                    "last_human_message_at": now,
+                }
+            },
+        )
+        return
+
+    if not validate_external_reply_body(new_reply_content):
+        logger.error(
+            "handoff_reply_leakage_guard handoff_id=%s account=%s",
+            handoff["_id"],
+            account_id,
+        )
+        return
+
+    external_recipient = handoff.get("external_sender") or ""
+    external_parent = await _latest_external_customer_message(
+        database,
+        account_id,
+        external_thread_id,
+        external_recipient,
+    )
+    if external_parent is None:
         external_parent = await _latest_external_message(database, account_id, external_thread_id)
     if external_parent is None:
         logger.warning("handoff_reply_missing_external_parent handoff_id=%s", handoff["_id"])
         return
 
     threading = threading_fields_from_parent(external_parent)
-    external_subject = handoff.get("external_subject") or external_parent.get("subject", "")
+    external_subject = external_reply_subject(
-    if not re.match(r"^re:\s*", external_subject, flags=re.IGNORECASE):
+        handoff.get("external_subject") or external_parent.get("subject", "")
-        external_subject = f"Re: {external_subject}"
+    )
 
-    external_recipient = handoff.get("external_sender") or external_parent.get("sender", {}).get("address")
+    external_recipient = external_recipient or external_parent.get("sender", {}).get("address")
     if not external_recipient:
         return
 
-    customer_body = inbound_body.strip()
+    customer_body = new_reply_content
     internet_message_id = await deliver_email(
         sender=agent_email,
         recipients=[external_recipient],
@@ -572,8 +658,8 @@ async def process_human_reply(
         }
     )
 
-    relay_body = f"Sent to customer:\n\n\"{customer_body}\""
+    relay_body = build_relay_confirmation_text(customer_body)
-    relay_subject = f"Re: {_handoff_subject(handoff.get('external_subject', ''))}"
+    relay_subject = _handoff_reply_subject(handoff.get("external_subject", ""))
     relay_threading = threading_fields_from_parent(human_message)
     relay_internet_id = await deliver_email(
         sender=agent_email,
@@ -656,7 +742,7 @@ async def maybe_trigger_handoff(
         existing = await find_active_handoff_for_external_thread(
             database, account_id, external_thread_id
         )
-        reason = evaluation.get("instruction_reason") or rule.get("instructions") or "Matched handoff rules."
+        reason = (rule.get("instructions") or "").strip() or "This conversation requires human attention."
         await send_handoff_to_human(
             database,
             account_id=account_id,

backend/app/services/reply_extractor.py

@@ -0,0 +1,119 @@
+import re
+from html import unescape
+
+# Patterns that mark the start of quoted previous-message content.
+TEXT_QUOTE_MARKERS = [
+    re.compile(r"\n-{2,}\s*Original Message\s*-{2,}", re.IGNORECASE),
+    re.compile(
+        r"\nOn .+? wrote:\s*\n",
+        re.IGNORECASE,
+    ),
+    re.compile(
+        r"\nOn .+?, .+? at .+? .+? wrote:\s*\n",
+        re.IGNORECASE,
+    ),
+    re.compile(
+        r"\nFrom:\s*.+\nSent:\s*.+\nTo:\s*.+\nSubject:\s*.+",
+        re.IGNORECASE,
+    ),
+    re.compile(r"\n_{5,}\n"),
+]
+
+HTML_QUOTE_PATTERNS = [
+    re.compile(r"<blockquote\b[^>]*>.*?</blockquote>", re.IGNORECASE | re.DOTALL),
+    re.compile(r'<div[^>]+class="[^"]*gmail_quote[^"]*"[^>]*>.*?</div>', re.IGNORECASE | re.DOTALL),
+    re.compile(r'<div[^>]+class="[^"]*gmail_attr[^"]*"[^>]*>.*?</div>', re.IGNORECASE | re.DOTALL),
+]
+
+PRIVATE_LEAK_MARKERS = [
+    "human handoff",
+    "a conversation needs your attention",
+    "why this was handed off",
+    "why you're receiving this",
+    "gentic human handoff",
+    "no handoff instructions were set",
+    "step passes",
+    "classifier returned",
+    "rule evaluation succeeded",
+    "reply normally to respond through",
+    "latest message",
+    "private agent ↔ human conversation",
+]
+
+
+def _normalize_newlines(text: str) -> str:
+    return text.replace("\r\n", "\n").replace("\r", "\n")
+
+
+def _html_to_text(html: str) -> str:
+    cleaned = html
+    for pattern in HTML_QUOTE_PATTERNS:
+        cleaned = pattern.sub("", cleaned)
+    cleaned = re.sub(r"<br\s*/?>", "\n", cleaned, flags=re.IGNORECASE)
+    cleaned = re.sub(r"</p\s*>", "\n", cleaned, flags=re.IGNORECASE)
+    cleaned = re.sub(r"<[^>]+>", "", cleaned)
+    return unescape(cleaned)
+
+
+def _strip_trailing_quoted_lines(text: str) -> str:
+    lines = text.split("\n")
+    kept: list[str] = []
+    for line in lines:
+        if re.match(r"^\s*>", line):
+            break
+        kept.append(line)
+    return "\n".join(kept).strip()
+
+
+def _split_at_quote_markers(text: str) -> tuple[str, str]:
+    normalized = _normalize_newlines(text)
+    earliest_index = None
+    for pattern in TEXT_QUOTE_MARKERS:
+        match = pattern.search(normalized)
+        if match and (earliest_index is None or match.start() < earliest_index):
+            earliest_index = match.start()
+    if earliest_index is not None:
+        new_content = normalized[:earliest_index].strip()
+        quoted = normalized[earliest_index:].strip()
+        return new_content, quoted
+    return _strip_trailing_quoted_lines(normalized), ""
+
+
+def extract_new_reply_content(
+    *,
+    body_text: str | None,
+    body_html: str | None = None,
+) -> dict[str, str]:
+    raw_text = _normalize_newlines((body_text or "").strip())
+    if body_html and not raw_text:
+        raw_text = _html_to_text(body_html).strip()
+
+    if body_html:
+        html_stripped = body_html
+        for pattern in HTML_QUOTE_PATTERNS:
+            html_stripped = pattern.sub("", html_stripped)
+        html_text = _html_to_text(html_stripped).strip()
+        if html_text:
+            new_from_html, quoted_from_html = _split_at_quote_markers(html_text)
+            if new_from_html:
+                return {
+                    "raw_body": raw_text or html_text,
+                    "new_reply_content": new_from_html,
+                    "quoted_content": quoted_from_html,
+                }
+
+    new_content, quoted_content = _split_at_quote_markers(raw_text)
+    return {
+        "raw_body": raw_text,
+        "new_reply_content": new_content,
+        "quoted_content": quoted_content,
+    }
+
+
+def validate_external_reply_body(body: str) -> bool:
+    normalized = (body or "").strip()
+    if not normalized:
+        return False
+    lower = normalized.lower()
+    hits = sum(1 for marker in PRIVATE_LEAK_MARKERS if marker in lower)
+    return hits == 0

backend/tests/test_reply_extractor.py

@@ -0,0 +1,63 @@
+from app.services.handoff_email_templates import external_reply_subject, handoff_email_subject
+from app.services.reply_extractor import extract_new_reply_content, validate_external_reply_body
+
+SCREENSHOT_REPLY = """ahan, did you receive a response?
+
+On Tue, Oct 6, 2026 at 2:11 AM <suyash@gentic.email> wrote:
+
+> Human Handoff
+>
+> A conversation needs your attention.
+>
+> From
+> 091rabbytes@gmail.com
+>
+> Subject
+> are you ready?
+>
+> Latest message
+> "lets start a threaddddd"
+>
+> Why this was handed off
+> No handoff instructions were set, so this step passes.
+>
+> Reply to this email to respond to the original sender through suyash@gentic.email.
+>
+> Your reply will be sent to the customer.
+>
+> Gentic Human Handoff"""
+
+
+def test_extracts_new_reply_from_gmail_quote():
+    result = extract_new_reply_content(body_text=SCREENSHOT_REPLY)
+    assert result["new_reply_content"] == "ahan, did you receive a response?"
+    assert "Human Handoff" in result["quoted_content"]
+    assert "091rabbytes@gmail.com" in result["quoted_content"]
+
+
+def test_extracted_reply_passes_leakage_guard():
+    result = extract_new_reply_content(body_text=SCREENSHOT_REPLY)
+    assert validate_external_reply_body(result["new_reply_content"]) is True
+
+
+def test_leakage_guard_blocks_private_template():
+    assert validate_external_reply_body(SCREENSHOT_REPLY) is False
+
+
+def test_external_reply_subject_uses_customer_subject():
+    assert external_reply_subject("are you ready?") == "Re: are you ready?"
+    assert external_reply_subject("Human Handoff · are you ready?") == "Re: are you ready?"
+
+
+def test_handoff_subject_format():
+    assert handoff_email_subject("are you ready?") == "Human Handoff · are you ready?"
+
+
+def test_outlook_original_message_split():
+    body = """Thanks for the update.
+
+-----Original Message-----
+From: support@gentic.email
+Subject: Human Handoff"""
+    result = extract_new_reply_content(body_text=body)
+    assert result["new_reply_content"] == "Thanks for the update."

frontend/src/components/HandoffConversation.jsx

@@ -2,6 +2,29 @@ import { ArrowLeft } from "lucide-react";
 import { useCallback, useEffect, useState } from "react";
 import { getHandoffConversation } from "../api";
 
+function HandoffMessageBody({ message }) {
+  const [showQuoted, setShowQuoted] = useState(false);
+  const displayText = message.new_reply_content || message.body_text || message.snippet;
+
+  return (
+    <>
+      <div className="handoff-message-body">{displayText}</div>
+      {message.has_quoted_text && message.raw_body && (
+        <button
+          type="button"
+          className="handoff-show-quoted"
+          onClick={() => setShowQuoted((current) => !current)}
+        >
+          {showQuoted ? "Hide quoted text" : "Show quoted text"}
+        </button>
+      )}
+      {showQuoted && message.raw_body && (
+        <pre className="handoff-quoted-body">{message.raw_body}</pre>
+      )}
+    </>
+  );
+}
+
 function formatTime(dateValue) {
   if (!dateValue) return "";
   return new Date(dateValue).toLocaleString(undefined, {
@@ -63,9 +86,7 @@ export default function HandoffConversation({ handoffId, onBack }) {
               <strong>{message.role === "human" ? "HUMAN OWNER" : "AGENT"}</strong>
               <time>{formatTime(message.event_at)}</time>
             </header>
-            <div className="handoff-message-body">
+            <HandoffMessageBody message={message} />
-              {message.body_text || message.snippet}
-            </div>
           </article>
         ))}
       </div>

frontend/src/styles.css

@@ -559,6 +559,8 @@ h1 em { color:var(--coral); font-style:normal; font-weight:500; }
 .handoff-message-human header strong { color:#11966a; }
 .handoff-message header time { color:#9a96a5; font-size:11px; }
 .handoff-message-body { color:#292536; font-size:13px; line-height:1.6; white-space:pre-wrap; }
+.handoff-show-quoted { margin-top:8px; padding:0; border:0; background:transparent; color:#6d5bd0; font-size:11px; font-weight:600; cursor:pointer; }
+.handoff-quoted-body { margin:8px 0 0; padding:10px 12px; border:1px solid #ece9f2; border-radius:8px; background:#faf9fc; color:#77758a; font-size:11px; line-height:1.45; white-space:pre-wrap; overflow:auto; }
 .handoff-settings-intro { margin-bottom:18px; padding:18px 20px; border:1px solid #ece7ff; border-radius:14px; background:#fbf9ff; }
 .handoff-settings-intro p { margin:0 0 10px; color:#4a4652; font-size:12px; line-height:1.6; }
 .handoff-settings-intro p strong { color:#171424; }