feat: add Connector Gateway UI and MCP wiring

backend/app/agent/factory/browser.py

@@ -25,7 +25,10 @@
     attach_remote_sub_agent_if_enabled,
 )
 from app.agent.listen_chat_agent import logger
-from app.agent.prompt import BROWSER_SYS_PROMPT
+from app.agent.prompt import (
+    BROWSER_SYS_PROMPT,
+    append_connected_app_mcp_notice,
+)
 from app.agent.toolkit.human_toolkit import HumanToolkit
 from app.agent.toolkit.hybrid_browser_toolkit import HybridBrowserToolkit
 
@@ -382,6 +385,7 @@ def browser_agent(
         now_str=NOW_STR,
         external_browser_notice=external_browser_notice,
     )
+    system_message = append_connected_app_mcp_notice(system_message)
     system_message = attach_remote_sub_agent_if_enabled(
         options=options,
         agent_name=Agents.browser_agent,

backend/app/agent/factory/developer.py

@@ -22,7 +22,10 @@
     attach_remote_sub_agent_if_enabled,
 )
 from app.agent.listen_chat_agent import logger
-from app.agent.prompt import DEVELOPER_SYS_PROMPT
+from app.agent.prompt import (
+    DEVELOPER_SYS_PROMPT,
+    append_connected_app_mcp_notice,
+)
 from app.agent.toolkit.human_toolkit import HumanToolkit
 
 # TODO: Remove NoteTakingToolkit and use TerminalToolkit instead
@@ -128,6 +131,7 @@ async def developer_agent(
         working_directory=working_directory,
         now_str=NOW_STR,
     )
+    system_message = append_connected_app_mcp_notice(system_message)
     system_message = attach_remote_sub_agent_if_enabled(
         options=options,
         agent_name=Agents.developer_agent,

backend/app/agent/factory/document.py

@@ -21,7 +21,10 @@
     attach_remote_sub_agent_if_enabled,
 )
 from app.agent.listen_chat_agent import logger
-from app.agent.prompt import DOCUMENT_SYS_PROMPT
+from app.agent.prompt import (
+    DOCUMENT_SYS_PROMPT,
+    append_connected_app_mcp_notice,
+)
 from app.agent.toolkit.excel_toolkit import ExcelToolkit
 from app.agent.toolkit.file_write_toolkit import FileToolkit
 from app.agent.toolkit.google_drive_mcp_toolkit import GoogleDriveMCPToolkit
@@ -154,6 +157,7 @@ async def document_agent(
         working_directory=working_directory,
         now_str=NOW_STR,
     )
+    system_message = append_connected_app_mcp_notice(system_message)
     system_message = attach_remote_sub_agent_if_enabled(
         options=options,
         agent_name=Agents.document_agent,

backend/app/agent/factory/mcp.py

@@ -19,7 +19,7 @@
     remote_sub_agent_enabled,
 )
 from app.agent.listen_chat_agent import logger
-from app.agent.prompt import MCP_SYS_PROMPT
+from app.agent.prompt import MCP_SYS_PROMPT, append_connected_app_mcp_notice
 from app.agent.toolkit.human_toolkit import HumanToolkit
 from app.agent.toolkit.mcp_search_toolkit import McpSearchToolkit
 from app.agent.tools import get_mcp_tools
@@ -73,7 +73,7 @@ async def mcp_agent(options: Chat):
         working_directory=working_directory,
         tools=tools,
         tool_names=tool_names,
-        system_message=MCP_SYS_PROMPT,
+        system_message=append_connected_app_mcp_notice(MCP_SYS_PROMPT),
         local_tool_description="local MCP or search tools",
         message_integration=message_integration,
     )

backend/app/agent/factory/multi_modal.py

@@ -23,7 +23,10 @@
     attach_remote_sub_agent_if_enabled,
 )
 from app.agent.listen_chat_agent import logger
-from app.agent.prompt import MULTI_MODAL_SYS_PROMPT
+from app.agent.prompt import (
+    MULTI_MODAL_SYS_PROMPT,
+    append_connected_app_mcp_notice,
+)
 from app.agent.toolkit.audio_analysis_toolkit import AudioAnalysisToolkit
 from app.agent.toolkit.human_toolkit import HumanToolkit
 
@@ -202,6 +205,7 @@ def multi_modal_agent(
         working_directory=working_directory,
         now_str=NOW_STR,
     )
+    system_message = append_connected_app_mcp_notice(system_message)
     system_message = attach_remote_sub_agent_if_enabled(
         options=options,
         agent_name=Agents.multi_modal_agent,

backend/app/agent/factory/question_confirm.py

@@ -13,14 +13,19 @@
 # ========= Copyright 2025-2026 @ Eigent.ai All Rights Reserved. =========
 
 from app.agent.agent_model import agent_model
-from app.agent.prompt import QUESTION_CONFIRM_SYS_PROMPT
+from app.agent.prompt import (
+    QUESTION_CONFIRM_SYS_PROMPT,
+    append_connected_app_mcp_notice,
+)
 from app.agent.utils import NOW_STR
 from app.model.chat import Chat
 
 
 def question_confirm_agent(options: Chat):
     return agent_model(
         "question_confirm_agent",
-        QUESTION_CONFIRM_SYS_PROMPT.format(now_str=NOW_STR),
+        append_connected_app_mcp_notice(
+            QUESTION_CONFIRM_SYS_PROMPT.format(now_str=NOW_STR)
+        ),
         options,
     )

backend/app/agent/factory/single_agent.py

@@ -21,7 +21,10 @@
 
 from app.agent.agent_model import agent_model
 from app.agent.factory.toolkit_assembler import assemble_single_agent_toolkits
-from app.agent.prompt import SINGLE_AGENT_SYS_PROMPT
+from app.agent.prompt import (
+    SINGLE_AGENT_SYS_PROMPT,
+    append_connected_app_mcp_notice,
+)
 from app.agent.utils import NOW_STR
 from app.hands.interface import IHands
 from app.model.chat import Chat
@@ -70,6 +73,7 @@ async def single_agent(
         working_directory=working_directory,
         now_str=NOW_STR,
     )
+    system_message = append_connected_app_mcp_notice(system_message)
 
     agent = agent_model(
         Agents.single_agent,

backend/app/agent/factory/social_media.py

@@ -19,7 +19,10 @@
     attach_remote_sub_agent_if_enabled,
 )
 from app.agent.listen_chat_agent import logger
-from app.agent.prompt import SOCIAL_MEDIA_SYS_PROMPT
+from app.agent.prompt import (
+    SOCIAL_MEDIA_SYS_PROMPT,
+    append_connected_app_mcp_notice,
+)
 from app.agent.toolkit.google_calendar_toolkit import GoogleCalendarToolkit
 from app.agent.toolkit.google_gmail_mcp_toolkit import GoogleGmailMCPToolkit
 from app.agent.toolkit.human_toolkit import HumanToolkit
@@ -110,6 +113,7 @@ async def social_media_agent(options: Chat):
     system_message = SOCIAL_MEDIA_SYS_PROMPT.format(
         working_directory=working_directory, now_str=NOW_STR
     )
+    system_message = append_connected_app_mcp_notice(system_message)
     system_message = attach_remote_sub_agent_if_enabled(
         options=options,
         agent_name=Agents.social_media_agent,

backend/app/agent/prompt.py

@@ -109,6 +109,29 @@ def build_remote_sub_agent_planning_notice() -> str:
     return REMOTE_SUB_AGENT_PLANNING_NOTICE
 
 
+CONNECTED_APP_MCP_NOTICE = """\
+<connected_app_tools>
+When the user asks to query or operate a third-party app that may already be
+connected, use available MCP or connector tools before browser/manual-login
+flows. Examples include Clerk, Slack, Gmail, Notion, GitHub, Google Calendar,
+Google Drive, Jira, Linear, Lark, Airtable, HubSpot, and similar SaaS apps.
+
+- Search or list the app's available actions first.
+- Execute read/list/search/count actions directly when the user's intent is
+  clear and all required input is available or optional.
+- Execute write/send/update/delete/admin actions only when the user explicitly
+  asked for that change and the target details are clear.
+- Ask for dashboard links, API keys, or manual browser login only after the
+  connector tools show the app/account/action is unavailable or required input
+  is missing.
+</connected_app_tools>
+"""
+
+
+def append_connected_app_mcp_notice(system_message: str) -> str:
+    return f"{system_message.rstrip()}\n\n{CONNECTED_APP_MCP_NOTICE}"
+
+
 SOCIAL_MEDIA_SYS_PROMPT = """\
 You are a Social Media Management Assistant with comprehensive capabilities
 across multiple platforms. You MUST use the `send_message_to_user` tool to

backend/app/service/chat_service.py

@@ -49,7 +49,10 @@
     remote_sub_agent_enabled,
 )
 from app.agent.listen_chat_agent import ListenChatAgent
-from app.agent.prompt import build_remote_sub_agent_planning_notice
+from app.agent.prompt import (
+    append_connected_app_mcp_notice,
+    build_remote_sub_agent_planning_notice,
+)
 from app.agent.toolkit.human_toolkit import HumanToolkit
 from app.agent.toolkit.note_taking_toolkit import NoteTakingToolkit
 from app.agent.toolkit.skill_toolkit import SkillToolkit
@@ -2867,6 +2870,9 @@ async def new_agent_model(
 For any date-related tasks, you MUST use this as \
 the current date.
 """
+    enhanced_description = append_connected_app_mcp_notice(
+        enhanced_description
+    )
     message_integration = ToolkitMessageIntegration(
         message_handler=HumanToolkit(
             options.project_id, data.name