diff --git a/plugins/Runner/LocalAgent/README.md b/plugins/Runner/LocalAgent/README.md
index 4214ad578..fae574ec5 100644
--- a/plugins/Runner/LocalAgent/README.md
+++ b/plugins/Runner/LocalAgent/README.md
@@ -6,6 +6,10 @@ Local Agent 是 LangBot 官方的进程内运行器。它在 LangBot 插件进
 
 `plugin:langbot-team/LocalAgent/default`
 
+## SDK 兼容性
+
+LocalAgent 0.2.3 使用 `langbot-plugin>=0.7.18,<0.8.0`，允许同一 0.7 系列的稳定补丁更新，不再精确锁定单个 SDK 版本。测试环境的 `uv.lock` 仍固定已验证版本以保证可复现；插件包的 `requirements.txt` 与项目声明使用相同的兼容范围。跨 0.8 系列升级需要单独验证。
+
 ## 主要能力
 
 - 支持主模型与 fallback 模型切换。
diff --git a/plugins/Runner/LocalAgent/manifest.yaml b/plugins/Runner/LocalAgent/manifest.yaml
index 9f114e15a..4079c78b6 100644
--- a/plugins/Runner/LocalAgent/manifest.yaml
+++ b/plugins/Runner/LocalAgent/manifest.yaml
@@ -3,7 +3,7 @@ kind: Plugin
 metadata:
   author: langbot-team
   name: LocalAgent
-  version: 0.2.2
+  version: 0.2.3
   repository: https://github.com/langbot-app/LangBot/tree/master/plugins/Runner/LocalAgent
   label:
     en_US: Local Agent
diff --git a/plugins/Runner/LocalAgent/pyproject.toml b/plugins/Runner/LocalAgent/pyproject.toml
index 1d93f02a7..67c1041e0 100644
--- a/plugins/Runner/LocalAgent/pyproject.toml
+++ b/plugins/Runner/LocalAgent/pyproject.toml
@@ -1,11 +1,11 @@
 [project]
 name = "langbot-local-agent"
-version = "0.2.2"
+version = "0.2.3"
 description = "Built-in agent with model fallback, tools, and knowledge retrieval"
 requires-python = ">=3.11,<4.0"
 dependencies = [
     "pydantic>=2.0.0",
-    "langbot-plugin==0.7.18",
+    "langbot-plugin>=0.7.18,<0.8.0",
 ]
 
 [project.optional-dependencies]
diff --git a/plugins/Runner/LocalAgent/requirements.txt b/plugins/Runner/LocalAgent/requirements.txt
index e72c24809..1130156db 100644
--- a/plugins/Runner/LocalAgent/requirements.txt
+++ b/plugins/Runner/LocalAgent/requirements.txt
@@ -1,2 +1,2 @@
-langbot-plugin==0.7.18
+langbot-plugin>=0.7.18,<0.8.0
 pydantic>=2.0.0
diff --git a/plugins/Runner/LocalAgent/tests/test_sdk_dependency_contract.py b/plugins/Runner/LocalAgent/tests/test_sdk_dependency_contract.py
new file mode 100644
index 000000000..b7a5cd282
--- /dev/null
+++ b/plugins/Runner/LocalAgent/tests/test_sdk_dependency_contract.py
@@ -0,0 +1,39 @@
+import tomllib
+from pathlib import Path
+
+import pytest
+import yaml
+from packaging.requirements import Requirement
+
+PLUGIN_ROOT = Path(__file__).resolve().parents[1]
+
+
+def _sdk_requirements():
+    project = tomllib.loads((PLUGIN_ROOT / "pyproject.toml").read_text())
+    packaged = (PLUGIN_ROOT / "requirements.txt").read_text().splitlines()
+    return [
+        next(Requirement(line) for line in requirements if line.startswith("langbot-plugin"))
+        for requirements in (project["project"]["dependencies"], packaged)
+    ]
+
+
+def test_project_and_packaged_sdk_constraints_match():
+    project, packaged = _sdk_requirements()
+    assert project.specifier == packaged.specifier
+    assert str(project.specifier) == "<0.8.0,>=0.7.18"
+
+
+@pytest.mark.parametrize("version", ["0.7.18", "0.7.19", "0.7.99"])
+def test_sdk_constraints_accept_compatible_stable_patches(version):
+    assert all(requirement.specifier.contains(version) for requirement in _sdk_requirements())
+
+
+@pytest.mark.parametrize("version", ["0.7.16", "0.7.17", "0.8.0", "1.0.0"])
+def test_sdk_constraints_reject_unverified_versions(version):
+    assert not any(requirement.specifier.contains(version) for requirement in _sdk_requirements())
+
+
+def test_manifest_and_project_versions_match():
+    project = tomllib.loads((PLUGIN_ROOT / "pyproject.toml").read_text())
+    manifest = yaml.safe_load((PLUGIN_ROOT / "manifest.yaml").read_text())
+    assert project["project"]["version"] == manifest["metadata"]["version"]
diff --git a/plugins/Runner/LocalAgent/uv.lock b/plugins/Runner/LocalAgent/uv.lock
index e3537f13e..4163b0818 100644
--- a/plugins/Runner/LocalAgent/uv.lock
+++ b/plugins/Runner/LocalAgent/uv.lock
@@ -456,7 +456,7 @@ wheels = [
 
 [[package]]
 name = "langbot-local-agent"
-version = "0.2.2"
+version = "0.2.3"
 source = { editable = "." }
 dependencies = [
     { name = "langbot-plugin" },
@@ -472,7 +472,7 @@ dev = [
 
 [package.metadata]
 requires-dist = [
-    { name = "langbot-plugin", specifier = "==0.7.18" },
+    { name = "langbot-plugin", specifier = ">=0.7.18,<0.8.0" },
     { name = "pydantic", specifier = ">=2.0.0" },
     { name = "pytest", marker = "extra == 'dev'", specifier = ">=7.0.0" },
     { name = "pytest-asyncio", marker = "extra == 'dev'", specifier = ">=0.21.0" },
diff --git a/plugins/catalog.json b/plugins/catalog.json
index 5c1621731..d829d2b0c 100644
--- a/plugins/catalog.json
+++ b/plugins/catalog.json
@@ -36,7 +36,7 @@
   },
   {
     "id": "langbot-team/LocalAgent",
-    "version": "0.2.2",
+    "version": "0.2.3",
     "category": "Runner",
     "path": "Runner/LocalAgent",
     "repository": "https://github.com/langbot-app/LangBot/tree/master/plugins/Runner/LocalAgent"
diff --git a/src/langbot/libs/qq_official_api/api.py b/src/langbot/libs/qq_official_api/api.py
index 4fedae5ca..5dce0ce9a 100644
--- a/src/langbot/libs/qq_official_api/api.py
+++ b/src/langbot/libs/qq_official_api/api.py
@@ -401,13 +401,21 @@ class QQOfficialClient:
         content_type = attachment.get('content_type', '')
         return content_type.startswith('image/')
 
+    def _resolve_msg_seq(self, msg_seq: Optional[int] = None) -> int:
+        """Allocate automatic sequences across message types, preserving explicit stream sequences."""
+        if msg_seq is None:
+            self._msg_seq_counter += 1
+            return self._msg_seq_counter
+        self._msg_seq_counter = max(self._msg_seq_counter, msg_seq)
+        return msg_seq
+
     async def send_private_text_msg(
         self,
         user_openid: str,
         content: str,
         msg_id: Optional[str] = None,
         event_id: Optional[str] = None,
-        msg_seq: int = 1,
+        msg_seq: Optional[int] = None,
     ):
         """Send a c2c text message.
 
@@ -427,7 +435,7 @@ class QQOfficialClient:
             data: dict[str, Any] = {
                 'content': content,
                 'msg_type': 0,
-                'msg_seq': msg_seq,
+                'msg_seq': self._resolve_msg_seq(msg_seq),
             }
             if msg_id:
                 data['msg_id'] = msg_id
@@ -448,7 +456,7 @@ class QQOfficialClient:
         content: str,
         msg_id: Optional[str] = None,
         event_id: Optional[str] = None,
-        msg_seq: int = 1,
+        msg_seq: Optional[int] = None,
     ) -> None:
         """Send a Markdown message to a C2C user or QQ group."""
         if not await self.check_access_token():
@@ -464,7 +472,7 @@ class QQOfficialClient:
         data: dict[str, Any] = {
             'msg_type': 2,
             'markdown': {'content': content},
-            'msg_seq': msg_seq,
+            'msg_seq': self._resolve_msg_seq(msg_seq),
         }
         if msg_id:
             data['msg_id'] = msg_id
@@ -488,7 +496,7 @@ class QQOfficialClient:
         content: str,
         msg_id: Optional[str] = None,
         event_id: Optional[str] = None,
-        msg_seq: int = 1,
+        msg_seq: Optional[int] = None,
     ) -> None:
         """Send a Markdown C2C message."""
         await self._send_markdown_msg('c2c', user_openid, content, msg_id, event_id, msg_seq)
@@ -499,7 +507,7 @@ class QQOfficialClient:
         content: str,
         msg_id: Optional[str] = None,
         event_id: Optional[str] = None,
-        msg_seq: int = 1,
+        msg_seq: Optional[int] = None,
     ) -> None:
         """Send a Markdown QQ group message."""
         await self._send_markdown_msg('group', group_openid, content, msg_id, event_id, msg_seq)
@@ -510,7 +518,7 @@ class QQOfficialClient:
         content: str,
         msg_id: Optional[str] = None,
         event_id: Optional[str] = None,
-        msg_seq: int = 1,
+        msg_seq: Optional[int] = None,
     ):
         """Send a group text message.
 
@@ -529,7 +537,7 @@ class QQOfficialClient:
             data: dict[str, Any] = {
                 'content': content,
                 'msg_type': 0,
-                'msg_seq': msg_seq,
+                'msg_seq': self._resolve_msg_seq(msg_seq),
             }
             if msg_id:
                 data['msg_id'] = msg_id
@@ -685,12 +693,10 @@ class QQOfficialClient:
         else:
             raise ValueError(f'Unsupported target_type: {target_type}')
 
-        self._msg_seq_counter += 1
-        msg_seq = self._msg_seq_counter
         body = {
             'msg_type': 7,
             'media': {'file_info': file_info},
-            'msg_seq': msg_seq,
+            'msg_seq': self._resolve_msg_seq(),
         }
         if content:
             body['content'] = content
@@ -792,7 +798,7 @@ class QQOfficialClient:
             'content_raw': content,
             'event_id': event_id,
             'msg_id': msg_id,
-            'msg_seq': msg_seq,
+            'msg_seq': self._resolve_msg_seq(msg_seq),
             'index': index,
         }
         if stream_msg_id:
@@ -817,7 +823,7 @@ class QQOfficialClient:
         keyboard: Optional[dict] = None,
         msg_id: Optional[str] = None,
         event_id: Optional[str] = None,
-        msg_seq: int = 1,
+        msg_seq: Optional[int] = None,
     ) -> dict:
         """Send a ``msg_type=2`` (markdown) message carrying a keyboard.
 
@@ -838,7 +844,7 @@ class QQOfficialClient:
             event_id: Use ``INTERACTION_CREATE`` event id from a prior
                 button click to keep within the 30-minute passive window
                 without an inbound msg_id.
-            msg_seq: De-dup counter when reusing msg_id.
+            msg_seq: Explicit de-dup counter, or None to allocate automatically.
         """
         if not await self.check_access_token():
             await self.get_access_token()
@@ -853,7 +859,7 @@ class QQOfficialClient:
         body: dict[str, Any] = {
             'msg_type': 2,
             'markdown': {'content': markdown_content},
-            'msg_seq': msg_seq,
+            'msg_seq': self._resolve_msg_seq(msg_seq),
         }
         if keyboard and keyboard.get('content', {}).get('rows'):
             body['keyboard'] = keyboard
diff --git a/src/langbot/pkg/platform/adapters/qqofficial/adapter.py b/src/langbot/pkg/platform/adapters/qqofficial/adapter.py
index d8dcad0c9..6a3fb351a 100644
--- a/src/langbot/pkg/platform/adapters/qqofficial/adapter.py
+++ b/src/langbot/pkg/platform/adapters/qqofficial/adapter.py
@@ -139,7 +139,9 @@ class QQOfficialAdapter(QQOfficialAPIMixin, abstract_platform_adapter.AbstractPl
         message: platform_message.MessageChain,
     ) -> platform_events.MessageResult:
         raw = await self._send_content_list(
-            str(target_type), str(target_id), await QQOfficialMessageConverter.yiri2target(message)
+            str(target_type),
+            str(target_id),
+            await QQOfficialMessageConverter.yiri2target(message, self._normalize_target_type(str(target_type))),
         )
         return platform_events.MessageResult(raw={'results': raw})
 
@@ -156,7 +158,7 @@ class QQOfficialAdapter(QQOfficialAPIMixin, abstract_platform_adapter.AbstractPl
         raw = await self._send_content_list(
             target_type,
             target_id,
-            await QQOfficialMessageConverter.yiri2target(message),
+            await QQOfficialMessageConverter.yiri2target(message, self._normalize_target_type(target_type)),
             msg_id=source.d_id,
         )
         return platform_events.MessageResult(message_id=source.d_id or source.id, raw={'results': raw})
@@ -177,7 +179,7 @@ class QQOfficialAdapter(QQOfficialAPIMixin, abstract_platform_adapter.AbstractPl
         *,
         msg_id: typing.Optional[str] = None,
         event_id: typing.Optional[str] = None,
-        msg_seq: int = 1,
+        msg_seq: typing.Optional[int] = None,
     ) -> typing.Any:
         """Send a text reply using the configured C2C/group render mode."""
         use_markdown = self.config.get('enable-markdown-rendering', False)
diff --git a/src/langbot/pkg/platform/adapters/qqofficial/message_converter.py b/src/langbot/pkg/platform/adapters/qqofficial/message_converter.py
index 545046f1a..ae3c935ab 100644
--- a/src/langbot/pkg/platform/adapters/qqofficial/message_converter.py
+++ b/src/langbot/pkg/platform/adapters/qqofficial/message_converter.py
@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import datetime
+import html
 import re
 
 from langbot.libs.qq_official_api.qqofficialevent import QQOfficialEvent
@@ -21,18 +22,35 @@ def _is_base64_data(value: str) -> bool:
 
 class QQOfficialMessageConverter(abstract_platform_adapter.AbstractMessageConverter):
     @staticmethod
-    async def yiri2target(message_chain: platform_message.MessageChain) -> list[dict]:
+    async def yiri2target(message_chain: platform_message.MessageChain, target_type: str | None = None) -> list[dict]:
         content_list: list[dict] = []
+        text_parts: list[str] = []
+
+        def flush_text() -> None:
+            content = ''.join(text_parts)
+            if content:
+                content_list.append({'type': 'text', 'content': content})
+            text_parts.clear()
+
         for component in message_chain:
             if isinstance(component, platform_message.Source):
                 continue
             if isinstance(component, platform_message.Plain):
-                content_list.append({'type': 'text', 'content': component.text})
+                text_parts.append(component.text)
+                continue
             elif isinstance(component, platform_message.At):
-                content_list.append({'type': 'text', 'content': f'@{component.display or component.target}'})
+                if target_type in {None, 'group', 'channel'}:
+                    target = html.escape(str(component.target), quote=True)
+                    text_parts.append(f'<qqbot-at-user id="{target}" />')
+                else:
+                    text_parts.append(f'@{component.display or component.target}')
+                continue
             elif isinstance(component, platform_message.AtAll):
-                content_list.append({'type': 'text', 'content': '@all'})
-            elif isinstance(component, platform_message.Image):
+                text_parts.append('<qqbot-at-everyone />' if target_type == 'channel' else '@all')
+                continue
+
+            flush_text()
+            if isinstance(component, platform_message.Image):
                 content_list.append(QQOfficialMessageConverter._media_payload(component, 'image'))
             elif isinstance(component, platform_message.Voice):
                 content_list.append(QQOfficialMessageConverter._media_payload(component, 'voice'))
@@ -44,15 +62,18 @@ class QQOfficialMessageConverter(abstract_platform_adapter.AbstractMessageConver
                 if component.id is not None:
                     content_list.append({'type': 'text', 'content': f'[Quote {component.id}]'})
                 if component.origin:
-                    content_list.extend(await QQOfficialMessageConverter.yiri2target(component.origin))
+                    content_list.extend(await QQOfficialMessageConverter.yiri2target(component.origin, target_type))
             elif isinstance(component, platform_message.Forward):
                 for node in component.node_list:
                     if node.message_chain:
-                        content_list.extend(await QQOfficialMessageConverter.yiri2target(node.message_chain))
+                        content_list.extend(
+                            await QQOfficialMessageConverter.yiri2target(node.message_chain, target_type)
+                        )
             else:
                 text = str(component)
                 if text:
                     content_list.append({'type': 'text', 'content': text})
+        flush_text()
         return content_list
 
     @staticmethod
diff --git a/src/langbot/pkg/platform/sources/qqofficial.py b/src/langbot/pkg/platform/sources/qqofficial.py
index fcc4c1a93..69c513ae1 100644
--- a/src/langbot/pkg/platform/sources/qqofficial.py
+++ b/src/langbot/pkg/platform/sources/qqofficial.py
@@ -387,7 +387,7 @@ class QQOfficialAdapter(abstract_platform_adapter.AbstractMessagePlatformAdapter
         *,
         msg_id: typing.Optional[str] = None,
         event_id: typing.Optional[str] = None,
-        msg_seq: int = 1,
+        msg_seq: typing.Optional[int] = None,
     ) -> None:
         """Send a text reply using the configured C2C/group render mode."""
         use_markdown = self.config.get('enable-markdown-rendering', False)
diff --git a/tests/fixtures/legacy_plugin_identity_sources.json b/tests/fixtures/legacy_plugin_identity_sources.json
index 89e22e7c8..da8609482 100644
--- a/tests/fixtures/legacy_plugin_identity_sources.json
+++ b/tests/fixtures/legacy_plugin_identity_sources.json
@@ -21,7 +21,7 @@
     "Runner/LocalAgent/components/runner/default.py": "49f80640d5b26442516b210cd9e65c452c9ce3a9909d6dbd1aa05e5bf3b232ac",
     "Runner/LocalAgent/components/runner/default.yaml": "c1364cf0f211162bb701e27ed92b351fd9ff4cfa0b4469cfeb83ad58136cdf47",
     "Runner/LocalAgent/main.py": "0cde45d7f6f411563fbded09be70d0a497c7c7999b5eaa27f83052383348277f",
-    "Runner/LocalAgent/manifest.yaml": "bc04121a6ffe73fee06c70634726216a6c45b656a350fdab7807d06403cad2cf",
+    "Runner/LocalAgent/manifest.yaml": "d4ccb50d83e83e452ab0b14822f245d5dc4bb85c7bc963ee467f299d4723063f",
     "Runner/LocalAgent/pkg/__init__.py": "ce5142b4971e8d7945fb3c202bacbc28011b033de0ddcb612d5d29106d6985ec",
     "Runner/LocalAgent/pkg/agent_core/__init__.py": "56e95f2391f796e17aee6a168603853ea78b59df97a136bfa33532aede2fa413",
     "Runner/LocalAgent/pkg/agent_core/langbot.py": "6bc0e6ee89e8ba3705d14545169f25f54a0c56dc5da89bd8384b3e22e3f21fea",
@@ -34,9 +34,9 @@
     "Runner/LocalAgent/pkg/model_calling.py": "3ebdb8900bb0de5b14e84bf027cc4ff01e59a4669d28dcede7ca3dcea3a3de4c",
     "Runner/LocalAgent/pkg/rag.py": "ea407af8d4f6fe5b00cde72c7d85ccc541d6fc46254188c372351d93da4a1f0f",
     "Runner/LocalAgent/pkg/run_assembly.py": "e1e2dd0029c976b6c0eb3763e5f94a369fd1909e8bf796a2cb84658c59727630",
-    "Runner/LocalAgent/pyproject.toml": "7f75c366ef0c6817c84cc906c9cd2783df9782876983ae6b15cb299a27409e62",
-    "Runner/LocalAgent/requirements.txt": "5c91c75dba82f776218d1e63541df3d2f444bb1f9354ea991826df57dad401c9",
-    "Runner/LocalAgent/uv.lock": "fc82991d3b2fadff999198c3c1ab35fc04eb8f64aa3f1f464aa93c87afa5ae01"
+    "Runner/LocalAgent/pyproject.toml": "18ec79e6bf40cca8d7b49df93489e2b3d9d74d820ac2f2032fb86d99b0b3cec4",
+    "Runner/LocalAgent/requirements.txt": "7ae9e2f4a957346c938f46dca3769c386c57cc4bc9044fd342358c0163d82bc4",
+    "Runner/LocalAgent/uv.lock": "6ee65461bcff71e93e0701ec91d56f298449144f708d83dd7dde3b1b8f548d05"
   },
   "root": "plugins"
 }
diff --git a/tests/unit_tests/platform/test_qqofficial_api.py b/tests/unit_tests/platform/test_qqofficial_api.py
index c0dfdf84c..7bec61a5a 100644
--- a/tests/unit_tests/platform/test_qqofficial_api.py
+++ b/tests/unit_tests/platform/test_qqofficial_api.py
@@ -194,14 +194,14 @@ async def test_qq_markdown_rendering_switches_c2c_and_group_text_replies():
         content='# Hello',
         msg_id='message-1',
         event_id=None,
-        msg_seq=1,
+        msg_seq=None,
     )
     adapter.bot.send_group_markdown_msg.assert_awaited_once_with(
         group_openid='group-1',
         content='* Hello',
         msg_id=None,
         event_id='event-1',
-        msg_seq=1,
+        msg_seq=None,
     )
     adapter.bot.send_private_text_msg.assert_not_awaited()
     adapter.bot.send_group_text_msg.assert_not_awaited()
diff --git a/tests/unit_tests/platform/test_qqofficial_eba_adapter.py b/tests/unit_tests/platform/test_qqofficial_eba_adapter.py
index a5aee2934..8a0aecec7 100644
--- a/tests/unit_tests/platform/test_qqofficial_eba_adapter.py
+++ b/tests/unit_tests/platform/test_qqofficial_eba_adapter.py
@@ -243,9 +243,7 @@ async def test_qqofficial_message_converter_maps_common_components_to_send_paylo
         )
     )
 
-    assert {'type': 'text', 'content': 'hi'} in payload
-    assert {'type': 'text', 'content': '@Alice'} in payload
-    assert {'type': 'text', 'content': '@all'} in payload
+    assert {'type': 'text', 'content': 'hi<qqbot-at-user id="user-1" />@all'} in payload
     assert any(item['type'] == 'image' and item['url'] == 'https://example.test/a.png' for item in payload)
     assert any(item['type'] == 'voice' and item['base64'].startswith('data:audio') for item in payload)
     assert any(item['type'] == 'file' and item['name'] == 'a.txt' for item in payload)
diff --git a/tests/unit_tests/platform/test_qqofficial_message_sequences.py b/tests/unit_tests/platform/test_qqofficial_message_sequences.py
new file mode 100644
index 000000000..a46a0ab12
--- /dev/null
+++ b/tests/unit_tests/platform/test_qqofficial_message_sequences.py
@@ -0,0 +1,223 @@
+import asyncio
+import json
+import time
+from types import SimpleNamespace
+from unittest.mock import AsyncMock
+
+import httpx
+import pytest
+import pytest_asyncio
+
+import langbot.pkg.core.app  # noqa: F401
+from langbot.libs.qq_official_api.api import QQOfficialClient
+from langbot.libs.qq_official_api.qqofficialevent import QQOfficialEvent
+from langbot.pkg.platform.adapters.qqofficial.adapter import QQOfficialAdapter
+from langbot.pkg.platform.adapters.qqofficial.event_converter import QQOfficialEventConverter
+from langbot.pkg.platform.adapters.qqofficial.message_converter import QQOfficialMessageConverter
+from langbot.pkg.platform.sources.qqofficial import QQOfficialAdapter as LegacyQQOfficialAdapter
+from langbot_plugin.api.entities.builtin.platform import message
+
+
+@pytest_asyncio.fixture
+async def captured_client():
+    requests = []
+
+    async def respond(request):
+        await asyncio.sleep(0)
+        requests.append((request.url.path, json.loads(request.content)))
+        return httpx.Response(200, json={'id': 'reply', 'file_info': 'uploaded-media'})
+
+    client = QQOfficialClient('fixture-secret', '', 'fixture-app', AsyncMock())
+    client.access_token = 'fixture-token'
+    client.access_token_expiry_time = time.time() + 3600
+    for timeout in (None, 30, 120):
+        client._http_clients[timeout] = httpx.AsyncClient(transport=httpx.MockTransport(respond))
+    try:
+        yield client, requests
+    finally:
+        await client.close()
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize('adapter_class', [QQOfficialAdapter, LegacyQQOfficialAdapter])
+@pytest.mark.parametrize('markdown', [False, True])
+@pytest.mark.parametrize('event_type', ['C2C_MESSAGE_CREATE', 'GROUP_AT_MESSAGE_CREATE', 'GROUP_MESSAGE_CREATE'])
+async def test_segmented_replies_share_sequences(captured_client, adapter_class, markdown, event_type):
+    client, requests = captured_client
+    adapter = adapter_class.model_construct(
+        bot=client, config={'enable-markdown-rendering': markdown}, logger=AsyncMock()
+    )
+    source = SimpleNamespace(
+        source_platform_object=QQOfficialEvent(
+            {'t': event_type, 'd_id': 'source-one', 'user_openid': 'user-one', 'group_openid': 'group-one'}
+        )
+    )
+    await adapter.reply_message(
+        source,
+        message.MessageChain(
+            [message.At(target='user-one'), message.Plain(text='first'), message.Plain(text='second')]
+        ),
+    )
+    await adapter.reply_message(source, message.MessageChain([message.Plain(text='follow-up')]))
+
+    payloads = [body for _, body in requests]
+    expected_sequences = [1, 2] if adapter_class is QQOfficialAdapter else [1, 2, 3]
+    assert [body['msg_seq'] for body in payloads] == expected_sequences
+    assert all(body['msg_id'] == 'source-one' for body in payloads)
+    assert all(body['msg_type'] == (2 if markdown else 0) for body in payloads)
+    expected_path = (
+        '/v2/users/user-one/messages' if event_type == 'C2C_MESSAGE_CREATE' else '/v2/groups/group-one/messages'
+    )
+    assert all(path == expected_path for path, _ in requests)
+    texts = [body['markdown']['content'] if markdown else body['content'] for body in payloads]
+    if adapter_class is QQOfficialAdapter:
+        mention = '@user-one' if event_type == 'C2C_MESSAGE_CREATE' else '<qqbot-at-user id="user-one" />'
+        assert texts == [f'{mention}firstsecond', 'follow-up']
+    else:
+        assert texts == ['first', 'second', 'follow-up']
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize('markdown', [False, True])
+@pytest.mark.parametrize('event_type', ['GROUP_AT_MESSAGE_CREATE', 'GROUP_MESSAGE_CREATE'])
+async def test_group_reply_mentions_original_sender_in_one_message(captured_client, markdown, event_type):
+    client, requests = captured_client
+    adapter = QQOfficialAdapter.model_construct(
+        bot=client, config={'enable-markdown-rendering': markdown}, logger=AsyncMock()
+    )
+    source = await QQOfficialEventConverter().target2yiri(
+        QQOfficialEvent(
+            {
+                't': event_type,
+                'd_id': 'source-one',
+                'member_openid': 'sender-openid',
+                'group_openid': 'group-one',
+                'content': 'hello',
+                'timestamp': '2026-10-28T10:00:00+0000',
+            }
+        )
+    )
+    await adapter.reply_message(
+        source,
+        message.MessageChain(
+            [
+                message.At(target=source.sender.id, display='Alice'),
+                message.Plain(text=' hello'),
+                message.Plain(text='!'),
+            ]
+        ),
+    )
+
+    assert len(requests) == 1
+    path, payload = requests[0]
+    assert path == '/v2/groups/group-one/messages'
+    assert payload['msg_id'] == 'source-one'
+    assert payload['msg_seq'] == 1
+    content = payload['markdown']['content'] if markdown else payload['content']
+    assert content == '<qqbot-at-user id="sender-openid" /> hello!'
+
+
+@pytest.mark.asyncio
+async def test_merged_text_preserves_media_order_and_sequences(captured_client):
+    client, requests = captured_client
+    adapter = QQOfficialAdapter.model_construct(bot=client, config={}, logger=AsyncMock())
+    source = SimpleNamespace(
+        source_platform_object=QQOfficialEvent(
+            {'t': 'GROUP_MESSAGE_CREATE', 'd_id': 'source-one', 'group_openid': 'group-one'}
+        )
+    )
+    await adapter.reply_message(
+        source,
+        message.MessageChain(
+            [
+                message.At(target='sender'),
+                message.Plain(text=' image:'),
+                message.Image(url='https://example.test/image.png'),
+                message.Plain(text='after'),
+                message.Plain(text=' image'),
+            ]
+        ),
+    )
+    payloads = [body for path, body in requests if path.endswith('/messages')]
+    assert [body['msg_seq'] for body in payloads] == [1, 2, 3]
+    assert [body['msg_type'] for body in payloads] == [0, 7, 0]
+    assert payloads[0]['content'] == '<qqbot-at-user id="sender" /> image:'
+    assert payloads[2]['content'] == 'after image'
+
+
+@pytest.mark.asyncio
+async def test_mentions_escape_ids_without_using_display_names():
+    payloads = await QQOfficialMessageConverter.yiri2target(
+        message.MessageChain([message.At(target='bad"/><qqbot-at-everyone', display='Alice')]), 'group'
+    )
+    assert payloads == [{'type': 'text', 'content': '<qqbot-at-user id="bad&quot;/&gt;&lt;qqbot-at-everyone" />'}]
+
+
+@pytest.mark.asyncio
+async def test_empty_text_does_not_emit_an_empty_message(captured_client):
+    client, requests = captured_client
+    adapter = QQOfficialAdapter.model_construct(bot=client, config={}, logger=AsyncMock())
+    await adapter.send_message('group', 'group-one', message.MessageChain([message.Plain(text='')]))
+    assert requests == []
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize('target_type', ['channel', 'guild'])
+async def test_channel_mentions_are_native_and_not_split(captured_client, target_type):
+    client, requests = captured_client
+    adapter = QQOfficialAdapter.model_construct(bot=client, config={}, logger=AsyncMock())
+    await adapter.send_message(
+        target_type,
+        'channel-one',
+        message.MessageChain([message.At(target='member'), message.AtAll(), message.Plain(text=' hello')]),
+    )
+    assert len(requests) == 1
+    assert requests[0][1]['content'] == '<qqbot-at-user id="member" /><qqbot-at-everyone /> hello'
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize('target_type', ['c2c', 'group'])
+async def test_text_media_markdown_and_keyboard_share_sequences(captured_client, target_type):
+    client, requests = captured_client
+    text_sender = client.send_private_text_msg if target_type == 'c2c' else client.send_group_text_msg
+    markdown_sender = client.send_private_markdown_msg if target_type == 'c2c' else client.send_group_markdown_msg
+    await text_sender('target', 'first', msg_id='source')
+    await client.send_image_msg(target_type, 'target', file_url='https://example.test/image.png', msg_id='source')
+    await markdown_sender('target', '**second**', msg_id='source')
+    await client.send_markdown_keyboard(target_type, 'target', 'third', {}, msg_id='source')
+    await text_sender('target', 'fourth', msg_id='source')
+
+    payloads = [body for path, body in requests if path.endswith('/messages')]
+    assert [body['msg_seq'] for body in payloads] == [1, 2, 3, 4, 5]
+    assert [body['msg_type'] for body in payloads] == [0, 7, 2, 2, 0]
+    assert all(body['msg_id'] == 'source' for body in payloads)
+
+
+@pytest.mark.asyncio
+async def test_concurrent_replies_do_not_reuse_sequences(captured_client):
+    client, requests = captured_client
+    await asyncio.gather(*(client.send_group_text_msg('group', str(index), msg_id='source') for index in range(20)))
+    assert sorted(body['msg_seq'] for _, body in requests) == list(range(1, 21))
+
+
+@pytest.mark.asyncio
+async def test_explicit_stream_sequence_is_preserved_and_reserved(captured_client):
+    client, requests = captured_client
+    await client.send_stream_msg('user', 'first', event_id='source', msg_id='source', msg_seq=7)
+    await client.send_stream_msg(
+        'user', 'final', event_id='source', msg_id='source', msg_seq=7, stream_msg_id='reply', input_state=10
+    )
+    await client.send_private_text_msg('user', 'follow-up', msg_id='source')
+    await client.send_private_markdown_msg('user', '**explicit**', msg_id='source', msg_seq=10)
+    await client.send_private_text_msg('user', 'automatic', msg_id='source')
+    assert [body['msg_seq'] for _, body in requests] == [7, 7, 8, 10, 11]
+
+
+@pytest.mark.asyncio
+async def test_failed_send_does_not_reuse_sequence(captured_client):
+    client, requests = captured_client
+    client._http_clients[None].post = AsyncMock(side_effect=httpx.ReadTimeout('response lost'))
+    with pytest.raises(httpx.ReadTimeout):
+        await client.send_group_text_msg('group', 'first', msg_id='source')
+    await client.send_markdown_keyboard('group', 'group', 'retry', {}, msg_id='source')
+    assert requests[0][1]['msg_seq'] == 2