fix(backend/chat): Fix bugs and remove dead code in SDK integration

- Fix message accumulation bug: reset has_appended_assistant when
  creating new post-tool assistant message to prevent lost text deltas
- Fix hardcoded model in anthropic_fallback.py: use config.model instead
  of hardcoded "claude-sonnet-4-20250514"
- Fix _SDK_TOOL_RESULTS_DIR using hardcoded /root/ path: use expanduser
- Remove unused create_strict_security_hooks (~75 lines)
- Remove unused create_heartbeat/create_usage from response adapter
- Remove unused RAW_TOOL_NAMES from tool_adapter
- Extract _MAX_TOOL_ITERATIONS constant from magic number

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

@@ -11,6 +11,7 @@ import uuid
 from collections.abc import AsyncGenerator
 from typing import Any, cast
 
+from ..config import ChatConfig
 from ..model import ChatMessage, ChatSession
 from ..response_model import (
     StreamBaseResponse,
@@ -27,6 +28,10 @@ from ..response_model import (
 from .tool_adapter import get_tool_definitions, get_tool_handlers
 
 logger = logging.getLogger(__name__)
+config = ChatConfig()
+
+# Maximum tool-call iterations before stopping to prevent infinite loops
+_MAX_TOOL_ITERATIONS = 10
 
 
 async def stream_with_anthropic(
@@ -72,14 +77,15 @@ async def stream_with_anthropic(
         )
 
     has_started_text = False
-    max_iterations = 10
     accumulated_text = ""
     accumulated_tool_calls: list[dict[str, Any]] = []
 
-    for _ in range(max_iterations):
+    for _ in range(_MAX_TOOL_ITERATIONS):
         try:
             async with client.messages.stream(
-                model="claude-sonnet-4-20250514",
+                model=(
+                    config.model.split("/")[-1] if "/" in config.model else config.model
+                ),
                 max_tokens=4096,
                 system=system_prompt,
                 messages=cast(Any, anthropic_messages),

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

@@ -24,7 +24,6 @@ from backend.api.features.chat.response_model import (
     StreamBaseResponse,
     StreamError,
     StreamFinish,
-    StreamHeartbeat,
     StreamStart,
     StreamTextDelta,
     StreamTextEnd,
@@ -32,7 +31,6 @@ from backend.api.features.chat.response_model import (
     StreamToolInputAvailable,
     StreamToolInputStart,
     StreamToolOutputAvailable,
-    StreamUsage,
 )
 
 logger = logging.getLogger(__name__)
@@ -141,18 +139,6 @@ class SDKResponseAdapter:
             responses.append(StreamTextEnd(id=self.text_block_id))
             self.has_ended_text = True
 
-    def create_heartbeat(self, tool_call_id: str | None = None) -> StreamHeartbeat:
-        """Create a heartbeat response."""
-        return StreamHeartbeat(toolCallId=tool_call_id)
-
-    def create_usage(self, prompt_tokens: int, completion_tokens: int) -> StreamUsage:
-        """Create a usage statistics response."""
-        return StreamUsage(
-            promptTokens=prompt_tokens,
-            completionTokens=completion_tokens,
-            totalTokens=prompt_tokens + completion_tokens,
-        )
-
 
 def _extract_tool_output(content: str | list[dict[str, str]] | None) -> str:
     """Extract a string output from a ToolResultBlock's content field."""

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

@@ -210,80 +210,3 @@ def create_security_hooks(user_id: str | None) -> dict[str, Any]:
     except ImportError:
         # Fallback for when SDK isn't available - return empty hooks
         return {}
-
-
-def create_strict_security_hooks(
-    user_id: str | None,
-    allowed_tools: list[str] | None = None,
-) -> dict[str, Any]:
-    """Create strict security hooks that only allow specific tools.
-
-    Args:
-        user_id: Current user ID
-        allowed_tools: List of allowed tool names (defaults to CoPilot tools)
-
-    Returns:
-        Hooks configuration dict
-    """
-    try:
-        from claude_agent_sdk import HookMatcher
-        from claude_agent_sdk.types import HookContext, HookInput, SyncHookJSONOutput
-
-        from .tool_adapter import RAW_TOOL_NAMES
-
-        tools_list = allowed_tools if allowed_tools is not None else RAW_TOOL_NAMES
-        allowed_set = set(tools_list)
-
-        async def strict_pre_tool_use(
-            input_data: HookInput,
-            tool_use_id: str | None,
-            context: HookContext,
-        ) -> SyncHookJSONOutput:
-            """Strict validation that only allows whitelisted tools."""
-            _ = context  # unused but required by signature
-            tool_name = cast(str, input_data.get("tool_name", ""))
-            tool_input = cast(dict[str, Any], input_data.get("tool_input", {}))
-
-            # Remove MCP prefix if present
-            clean_name = tool_name.removeprefix(MCP_TOOL_PREFIX)
-
-            if clean_name not in allowed_set:
-                logger.warning(f"Blocked non-whitelisted tool: {tool_name}")
-                return cast(
-                    SyncHookJSONOutput,
-                    {
-                        "hookSpecificOutput": {
-                            "hookEventName": "PreToolUse",
-                            "permissionDecision": "deny",
-                            "permissionDecisionReason": (
-                                f"Tool '{tool_name}' is not in the allowed list"
-                            ),
-                        }
-                    },
-                )
-
-            # 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:
-                return cast(SyncHookJSONOutput, result)
-
-            logger.debug(
-                f"[SDK Audit] Tool call: tool={tool_name}, "
-                f"user={user_id}, tool_use_id={tool_use_id}"
-            )
-            return cast(SyncHookJSONOutput, {})
-
-        return {
-            "PreToolUse": [
-                HookMatcher(matcher="*", hooks=[strict_pre_tool_use]),
-            ],
-        }
-    except ImportError:
-        return {}

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

@@ -291,13 +291,17 @@ async def stream_chat_completion_sdk(
 
                             if isinstance(response, StreamTextDelta):
                                 delta = response.delta or ""
+                                # After tool results, start a new assistant
+                                # message for the post-tool text.
                                 if has_tool_results and has_appended_assistant:
                                     assistant_response = ChatMessage(
                                         role="assistant", content=delta
                                     )
                                     accumulated_tool_calls = []
-                                    session.messages.append(assistant_response)
+                                    has_appended_assistant = False
                                     has_tool_results = False
+                                    session.messages.append(assistant_response)
+                                    has_appended_assistant = True
                                 else:
                                     assistant_response.content = (
                                         assistant_response.content or ""

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

@@ -18,7 +18,7 @@ from backend.api.features.chat.tools.base import BaseTool
 logger = logging.getLogger(__name__)
 
 # Allowed base directory for the Read tool (SDK saves oversized tool results here)
-_SDK_TOOL_RESULTS_DIR = "/root/.claude/"
+_SDK_TOOL_RESULTS_DIR = os.path.expanduser("~/.claude/")
 
 # MCP server naming - the SDK prefixes tool names as "mcp__{server_name}__{tool}"
 MCP_SERVER_NAME = "copilot"
@@ -282,6 +282,3 @@ COPILOT_TOOL_NAMES = [
     *[f"{MCP_TOOL_PREFIX}{name}" for name in TOOL_REGISTRY.keys()],
     f"{MCP_TOOL_PREFIX}{_READ_TOOL_NAME}",
 ]
-
-# Also export the raw tool names for flexibility
-RAW_TOOL_NAMES = list(TOOL_REGISTRY.keys())