fix(backend/chat): Allow MCP-registered tools through security hook and fix title generation

- Skip BLOCKED_TOOLS check for tools with mcp__copilot__ prefix since they
  are already sandboxed by tool_adapter (fixes Read tool being blocked)
- Fall back to session.messages for title generation when message=None

autogpt_platform/backend/backend/api/features/chat/sdk/security_hooks.py

@@ -138,12 +138,15 @@ def create_security_hooks(user_id: str | None) -> dict[str, Any]:
             tool_input = cast(dict[str, Any], input_data.get("tool_input", {}))
 
             # Strip MCP prefix for consistent validation
+            is_copilot_tool = tool_name.startswith(MCP_TOOL_PREFIX)
             clean_name = tool_name.removeprefix(MCP_TOOL_PREFIX)
 
-            # Validate basic tool access
-            result = _validate_tool_access(clean_name, tool_input)
-            if result:
-                return cast(SyncHookJSONOutput, result)
+            # Only block non-CoPilot tools; our MCP-registered tools
+            # (including Read for oversized results) are already sandboxed.
+            if not is_copilot_tool:
+                result = _validate_tool_access(clean_name, tool_input)
+                if result:
+                    return cast(SyncHookJSONOutput, result)
 
             # Validate user isolation
             result = _validate_user_isolation(clean_name, tool_input, user_id)
@@ -259,10 +262,13 @@ def create_strict_security_hooks(
                     },
                 )
 
-            # Run standard validations using clean_name for consistent checks
-            result = _validate_tool_access(clean_name, tool_input)
-            if result:
-                return cast(SyncHookJSONOutput, result)
+            # Only run blocklist check for non-CoPilot tools; whitelisted
+            # MCP tools are already sandboxed by tool_adapter.
+            is_copilot_tool = tool_name.startswith(MCP_TOOL_PREFIX)
+            if not is_copilot_tool:
+                result = _validate_tool_access(clean_name, tool_input)
+                if result:
+                    return cast(SyncHookJSONOutput, result)
 
             result = _validate_user_isolation(clean_name, tool_input, user_id)
             if result:

autogpt_platform/backend/backend/api/features/chat/service.py

@@ -452,8 +452,9 @@ async def stream_chat_completion(
 
     # Generate title for new sessions on first user message (non-blocking)
     # Check: is_user_message, no title yet, and this is the first user message
-    if is_user_message and message and not session.title:
-        user_messages = [m for m in session.messages if m.role == "user"]
+    user_messages = [m for m in session.messages if m.role == "user"]
+    first_user_msg = message or (user_messages[0].content if user_messages else None)
+    if is_user_message and first_user_msg and not session.title:
         if len(user_messages) == 1:
             # First user message - generate title in background
             import asyncio
@@ -461,7 +462,7 @@ async def stream_chat_completion(
             # Capture only the values we need (not the session object) to avoid
             # stale data issues when the main flow modifies the session
             captured_session_id = session_id
-            captured_message = message
+            captured_message = first_user_msg
             captured_user_id = user_id
 
             async def _update_title():