"""loop Main agent implementation with integrated tool system and MCP support """ import asyncio import json import logging import os from litellm import ChatCompletionMessageToolCall, Message, acompletion from litellm.exceptions import ContextWindowExceededError from agent.config import Config from agent.core.session import Event, OpType, Session from agent.core.tools import ToolRouter from agent.tools.jobs_tool import CPU_FLAVORS logger = logging.getLogger(__name__) ToolCall = ChatCompletionMessageToolCall # Explicit inference token for LLM API calls (separate from user OAuth tokens). _INFERENCE_API_KEY = os.environ.get("INFERENCE_TOKEN") def _resolve_hf_router_params(model_name: str) -> dict: """ Build LiteLLM kwargs for HuggingFace Router models. api-inference.huggingface.co is deprecated; the new router lives at router.huggingface.co//v3/openai. LiteLLM's built-in ``huggingface/`` provider still targets the old endpoint, so we rewrite model names to ``openai/`` and supply the correct api_base. Input format: huggingface/// Example: huggingface/novita/moonshotai/kimi-k2.5 """ if not model_name.startswith("huggingface/"): return {"model": model_name} parts = model_name.split( "/", 2 ) # ['huggingface', 'novita', 'moonshotai/kimi-k2.5'] if len(parts) < 3: return {"model": model_name} router_provider = parts[1] actual_model = parts[2] api_key = _INFERENCE_API_KEY return { "model": f"openai/{actual_model}", "api_base": f"https://router.huggingface.co/{router_provider}/v3/openai", "api_key": api_key, } def _validate_tool_args(tool_args: dict) -> tuple[bool, str | None]: """ Validate tool arguments structure. Returns: (is_valid, error_message) """ args = tool_args.get("args", {}) # Sometimes LLM passes args as string instead of dict if isinstance(args, str): return ( False, f"Tool call error: 'args' must be a JSON object, not a string. You passed: {repr(args)}", ) if not isinstance(args, dict) and args is not None: return ( False, f"Tool call error: 'args' must be a JSON object. You passed type: {type(args).__name__}", ) return True, None def _needs_approval( tool_name: str, tool_args: dict, config: Config | None = None ) -> bool: """Check if a tool call requires user approval before execution.""" # Yolo mode: skip all approvals if config and config.yolo_mode: return False # If args are malformed, skip approval (validation error will be shown later) args_valid, _ = _validate_tool_args(tool_args) if not args_valid: return False if tool_name == "sandbox_create": return True if tool_name == "hf_jobs": operation = tool_args.get("operation", "") if operation not in ["run", "uv", "scheduled run", "scheduled uv"]: return False # Check if this is a CPU-only job # hardware_flavor is at top level of tool_args, not nested in args hardware_flavor = ( tool_args.get("hardware_flavor") or tool_args.get("flavor") or tool_args.get("hardware") or "cpu-basic" ) is_cpu_job = hardware_flavor in CPU_FLAVORS if is_cpu_job: if config and not config.confirm_cpu_jobs: return False return True return True # Check for file upload operations (hf_private_repos or other tools) if tool_name == "hf_private_repos": operation = tool_args.get("operation", "") if operation == "upload_file": if config and config.auto_file_upload: return False return True # Other operations (create_repo, etc.) always require approval if operation in ["create_repo"]: return True # hf_repo_files: upload (can overwrite) and delete require approval if tool_name == "hf_repo_files": operation = tool_args.get("operation", "") if operation in ["upload", "delete"]: return True # hf_repo_git: destructive operations require approval if tool_name == "hf_repo_git": operation = tool_args.get("operation", "") if operation in [ "delete_branch", "delete_tag", "merge_pr", "create_repo", "update_repo", ]: return True return False async def _compact_and_notify(session: Session) -> None: """Run compaction and send event if context was reduced.""" old_length = session.context_manager.context_length tool_specs = session.tool_router.get_tool_specs_for_llm() await session.context_manager.compact( model_name=session.config.model_name, tool_specs=tool_specs, ) new_length = session.context_manager.context_length if new_length != old_length: await session.send_event( Event( event_type="compacted", data={"old_tokens": old_length, "new_tokens": new_length}, ) ) class Handlers: """Handler functions for each operation type""" @staticmethod async def _abandon_pending_approval(session: Session) -> None: """Cancel pending approval tools when the user continues the conversation. Injects rejection tool-result messages into the LLM context (so the history stays valid) and notifies the frontend that those tools were abandoned. """ tool_calls = session.pending_approval.get("tool_calls", []) for tc in tool_calls: tool_name = tc.function.name abandon_msg = ( "Task abandoned — user continued the conversation without approving." ) # Keep LLM context valid: every tool_call needs a tool result tool_msg = Message( role="tool", content=abandon_msg, tool_call_id=tc.id, name=tool_name, ) session.context_manager.add_message(tool_msg) await session.send_event( Event( event_type="tool_state_change", data={ "tool_call_id": tc.id, "tool": tool_name, "state": "abandoned", }, ) ) session.pending_approval = None logger.info("Abandoned %d pending approval tool(s)", len(tool_calls)) @staticmethod async def run_agent( session: Session, text: str, max_iterations: int = 300 ) -> str | None: """ Handle user input (like user_input_or_turn in codex.rs:1291) Returns the final assistant response content, if any. """ # Clear any stale cancellation flag from a previous run session.reset_cancel() # If there's a pending approval and the user sent a new message, # abandon the pending tools so the LLM context stays valid. if text and session.pending_approval: await Handlers._abandon_pending_approval(session) # Add user message to history only if there's actual content if text: user_msg = Message(role="user", content=text) session.context_manager.add_message(user_msg) # Send event that we're processing await session.send_event( Event(event_type="processing", data={"message": "Processing user input"}) ) # Agentic loop - continue until model doesn't call tools or max iterations is reached iteration = 0 final_response = None errored = False while iteration < max_iterations: # ── Cancellation check: before LLM call ── if session.is_cancelled: break # Compact before calling the LLM if context is near the limit await _compact_and_notify(session) messages = session.context_manager.get_messages() tools = session.tool_router.get_tool_specs_for_llm() try: # ── Stream the LLM response ────────────────────────── llm_params = _resolve_hf_router_params(session.config.model_name) response = await acompletion( messages=messages, tools=tools, tool_choice="auto", stream=True, stream_options={"include_usage": True}, **llm_params, ) full_content = "" tool_calls_acc: dict[int, dict] = {} token_count = 0 finish_reason = None async for chunk in response: # ── Check cancellation during streaming ── if session.is_cancelled: tool_calls_acc.clear() break choice = chunk.choices[0] if chunk.choices else None if not choice: # Last chunk may carry only usage info if hasattr(chunk, "usage") and chunk.usage: token_count = chunk.usage.total_tokens continue delta = choice.delta if choice.finish_reason: finish_reason = choice.finish_reason # Stream text deltas to the frontend if delta.content: full_content += delta.content await session.send_event( Event( event_type="assistant_chunk", data={"content": delta.content}, ) ) # Accumulate tool-call deltas (name + args arrive in pieces) if delta.tool_calls: for tc_delta in delta.tool_calls: idx = tc_delta.index if idx not in tool_calls_acc: tool_calls_acc[idx] = { "id": "", "type": "function", "function": {"name": "", "arguments": ""}, } if tc_delta.id: tool_calls_acc[idx]["id"] = tc_delta.id if tc_delta.function: if tc_delta.function.name: tool_calls_acc[idx]["function"]["name"] += ( tc_delta.function.name ) if tc_delta.function.arguments: tool_calls_acc[idx]["function"]["arguments"] += ( tc_delta.function.arguments ) # Capture usage from the final chunk if hasattr(chunk, "usage") and chunk.usage: token_count = chunk.usage.total_tokens # ── Stream finished — reconstruct full message ─────── content = full_content or None # If output was truncated, all tool call args are garbage if finish_reason == "length" and tool_calls_acc: logger.warning("Output truncated (finish_reason=length) — dropping tool calls") tool_calls_acc.clear() # Build tool_calls list from accumulated deltas tool_calls: list[ToolCall] = [] for idx in sorted(tool_calls_acc.keys()): tc_data = tool_calls_acc[idx] tool_calls.append( ToolCall( id=tc_data["id"], type="function", function={ "name": tc_data["function"]["name"], "arguments": tc_data["function"]["arguments"], }, ) ) # Signal end of streaming to the frontend await session.send_event( Event(event_type="assistant_stream_end", data={}) ) # If no tool calls, add assistant message and we're done if not tool_calls: if content: assistant_msg = Message(role="assistant", content=content) session.context_manager.add_message(assistant_msg, token_count) final_response = content break # Validate tool call args (one json.loads per call, once) # and split into good vs bad good_tools: list[tuple[ToolCall, str, dict]] = [] bad_tools: list[ToolCall] = [] for tc in tool_calls: try: args = json.loads(tc.function.arguments) good_tools.append((tc, tc.function.name, args)) except (json.JSONDecodeError, TypeError, ValueError): logger.warning( "Malformed arguments for tool_call %s (%s) — skipping", tc.id, tc.function.name, ) tc.function.arguments = "{}" bad_tools.append(tc) # Add assistant message with all tool calls to context assistant_msg = Message( role="assistant", content=content, tool_calls=tool_calls, ) session.context_manager.add_message(assistant_msg, token_count) # Add error results for bad tool calls so the LLM # knows what happened and can retry differently for tc in bad_tools: error_msg = ( f"ERROR: Tool call to '{tc.function.name}' had malformed JSON " f"arguments and was NOT executed. Retry with smaller content — " f"for 'write', split into multiple smaller writes using 'edit'." ) session.context_manager.add_message(Message( role="tool", content=error_msg, tool_call_id=tc.id, name=tc.function.name, )) await session.send_event(Event( event_type="tool_call", data={"tool": tc.function.name, "arguments": {}, "tool_call_id": tc.id}, )) await session.send_event(Event( event_type="tool_output", data={"tool": tc.function.name, "tool_call_id": tc.id, "output": error_msg, "success": False}, )) # ── Cancellation check: before tool execution ── if session.is_cancelled: break # Separate good tools into approval-required vs auto-execute approval_required_tools: list[tuple[ToolCall, str, dict]] = [] non_approval_tools: list[tuple[ToolCall, str, dict]] = [] for tc, tool_name, tool_args in good_tools: if _needs_approval(tool_name, tool_args, session.config): approval_required_tools.append((tc, tool_name, tool_args)) else: non_approval_tools.append((tc, tool_name, tool_args)) # Execute non-approval tools (in parallel when possible) if non_approval_tools: # 1. Validate args upfront parsed_tools: list[ tuple[ToolCall, str, dict, bool, str] ] = [] for tc, tool_name, tool_args in non_approval_tools: args_valid, error_msg = _validate_tool_args(tool_args) parsed_tools.append( (tc, tool_name, tool_args, args_valid, error_msg) ) # 2. Send all tool_call events upfront (so frontend shows them all) for tc, tool_name, tool_args, args_valid, _ in parsed_tools: if args_valid: await session.send_event( Event( event_type="tool_call", data={ "tool": tool_name, "arguments": tool_args, "tool_call_id": tc.id, }, ) ) # 3. Execute all valid tools in parallel, cancellable async def _exec_tool( tc: ToolCall, name: str, args: dict, valid: bool, err: str, ) -> tuple[ToolCall, str, dict, str, bool]: if not valid: return (tc, name, args, err, False) out, ok = await session.tool_router.call_tool( name, args, session=session ) return (tc, name, args, out, ok) gather_task = asyncio.ensure_future(asyncio.gather( *[ _exec_tool(tc, name, args, valid, err) for tc, name, args, valid, err in parsed_tools ] )) cancel_task = asyncio.ensure_future(session._cancelled.wait()) done, _ = await asyncio.wait( [gather_task, cancel_task], return_when=asyncio.FIRST_COMPLETED, ) if cancel_task in done: gather_task.cancel() try: await gather_task except asyncio.CancelledError: pass break cancel_task.cancel() results = gather_task.result() # 4. Record results and send outputs (order preserved) for tc, tool_name, tool_args, output, success in results: tool_msg = Message( role="tool", content=output, tool_call_id=tc.id, name=tool_name, ) session.context_manager.add_message(tool_msg) await session.send_event( Event( event_type="tool_output", data={ "tool": tool_name, "tool_call_id": tc.id, "output": output, "success": success, }, ) ) # If there are tools requiring approval, ask for batch approval if approval_required_tools: # Prepare batch approval data tools_data = [] for tc, tool_name, tool_args in approval_required_tools: # Resolve sandbox file paths for hf_jobs scripts so the # frontend can display & edit the actual file content. if tool_name == "hf_jobs" and isinstance(tool_args.get("script"), str): from agent.tools.sandbox_tool import resolve_sandbox_script sandbox = getattr(session, "sandbox", None) resolved, _ = await resolve_sandbox_script(sandbox, tool_args["script"]) if resolved: tool_args = {**tool_args, "script": resolved} tools_data.append({ "tool": tool_name, "arguments": tool_args, "tool_call_id": tc.id, }) await session.send_event(Event( event_type="approval_required", data={"tools": tools_data, "count": len(tools_data)}, )) # Store all approval-requiring tools (ToolCall objects for execution) session.pending_approval = { "tool_calls": [tc for tc, _, _ in approval_required_tools], } # Return early - wait for EXEC_APPROVAL operation return None iteration += 1 except ContextWindowExceededError: # Force compact and retry this iteration session.context_manager.context_length = ( session.context_manager.max_context + 1 ) await _compact_and_notify(session) continue except Exception as e: import traceback await session.send_event( Event( event_type="error", data={"error": str(e) + "\n" + traceback.format_exc()}, ) ) errored = True break if session.is_cancelled: await session.send_event(Event(event_type="interrupted")) elif not errored: await session.send_event( Event( event_type="turn_complete", data={"history_size": len(session.context_manager.items)}, ) ) # Increment turn counter and check for auto-save session.increment_turn() await session.auto_save_if_needed() return final_response @staticmethod async def undo(session: Session) -> None: """Remove the last complete turn and notify the frontend.""" removed = session.context_manager.undo_last_turn() if not removed: logger.warning("Undo: no user message found to remove") await session.send_event(Event(event_type="undo_complete")) @staticmethod async def exec_approval(session: Session, approvals: list[dict]) -> None: """Handle batch job execution approval""" if not session.pending_approval: await session.send_event( Event( event_type="error", data={"error": "No pending approval to process"}, ) ) return tool_calls = session.pending_approval.get("tool_calls", []) if not tool_calls: await session.send_event( Event( event_type="error", data={"error": "No pending tool calls found"}, ) ) return # Create a map of tool_call_id -> approval decision approval_map = {a["tool_call_id"]: a for a in approvals} for a in approvals: if a.get("edited_script"): logger.info( f"Received edited script for tool_call {a['tool_call_id']} ({len(a['edited_script'])} chars)" ) # Separate approved and rejected tool calls approved_tasks = [] rejected_tasks = [] for tc in tool_calls: tool_name = tc.function.name try: tool_args = json.loads(tc.function.arguments) except (json.JSONDecodeError, TypeError) as e: # Malformed arguments — treat as failed, notify agent logger.warning(f"Malformed tool arguments for {tool_name}: {e}") tool_msg = Message( role="tool", content=f"Malformed arguments: {e}", tool_call_id=tc.id, name=tool_name, ) session.context_manager.add_message(tool_msg) await session.send_event( Event( event_type="tool_output", data={ "tool": tool_name, "tool_call_id": tc.id, "output": f"Malformed arguments: {e}", "success": False, }, ) ) continue approval_decision = approval_map.get(tc.id, {"approved": False}) if approval_decision.get("approved", False): edited_script = approval_decision.get("edited_script") was_edited = False if edited_script and "script" in tool_args: tool_args["script"] = edited_script was_edited = True logger.info(f"Using user-edited script for {tool_name} ({tc.id})") approved_tasks.append((tc, tool_name, tool_args, was_edited)) else: rejected_tasks.append((tc, tool_name, approval_decision)) # Clear pending approval immediately so a page refresh during # execution won't re-show the approval dialog. session.pending_approval = None # Notify frontend of approval decisions immediately (before execution) for tc, tool_name, tool_args, _was_edited in approved_tasks: await session.send_event( Event( event_type="tool_state_change", data={ "tool_call_id": tc.id, "tool": tool_name, "state": "approved", }, ) ) for tc, tool_name, approval_decision in rejected_tasks: await session.send_event( Event( event_type="tool_state_change", data={ "tool_call_id": tc.id, "tool": tool_name, "state": "rejected", }, ) ) # Execute all approved tools concurrently async def execute_tool(tc, tool_name, tool_args, was_edited): """Execute a single tool and return its result. The TraceLog already exists on the frontend (created by approval_required), so we send tool_state_change instead of tool_call to avoid creating a duplicate. """ await session.send_event( Event( event_type="tool_state_change", data={ "tool_call_id": tc.id, "tool": tool_name, "state": "running", }, ) ) output, success = await session.tool_router.call_tool( tool_name, tool_args, session=session, tool_call_id=tc.id ) return (tc, tool_name, output, success, was_edited) # Execute all approved tools concurrently and wait for ALL to complete if approved_tasks: results = await asyncio.gather( *[ execute_tool(tc, tool_name, tool_args, was_edited) for tc, tool_name, tool_args, was_edited in approved_tasks ], return_exceptions=True, ) # Process results and add to context for result in results: if isinstance(result, Exception): # Handle execution error logger.error(f"Tool execution error: {result}") continue tc, tool_name, output, success, was_edited = result if was_edited: output = f"[Note: The user edited the script before execution. The output below reflects the user-modified version, not your original script.]\n\n{output}" # Add tool result to context tool_msg = Message( role="tool", content=output, tool_call_id=tc.id, name=tool_name, ) session.context_manager.add_message(tool_msg) await session.send_event( Event( event_type="tool_output", data={ "tool": tool_name, "tool_call_id": tc.id, "output": output, "success": success, }, ) ) # Process rejected tools for tc, tool_name, approval_decision in rejected_tasks: rejection_msg = "Job execution cancelled by user" user_feedback = approval_decision.get("feedback") if user_feedback: # Ensure feedback is a string and sanitize any problematic characters feedback_str = str(user_feedback).strip() # Remove any control characters that might break JSON parsing feedback_str = "".join( char for char in feedback_str if ord(char) >= 32 or char in "\n\t" ) rejection_msg += f". User feedback: {feedback_str}" # Ensure rejection_msg is a clean string rejection_msg = str(rejection_msg).strip() tool_msg = Message( role="tool", content=rejection_msg, tool_call_id=tc.id, name=tool_name, ) session.context_manager.add_message(tool_msg) await session.send_event( Event( event_type="tool_output", data={ "tool": tool_name, "tool_call_id": tc.id, "output": rejection_msg, "success": False, }, ) ) # Continue agent loop with empty input to process the tool results await Handlers.run_agent(session, "") @staticmethod async def shutdown(session: Session) -> bool: """Handle shutdown (like shutdown in codex.rs:1329)""" # Save session trajectory if enabled (fire-and-forget, returns immediately) if session.config.save_sessions: logger.info("Saving session...") repo_id = session.config.session_dataset_repo _ = session.save_and_upload_detached(repo_id) session.is_running = False await session.send_event(Event(event_type="shutdown")) return True async def process_submission(session: Session, submission) -> bool: """ Process a single submission and return whether to continue running. Returns: bool: True to continue, False to shutdown """ op = submission.operation logger.debug("Received operation: %s", op.op_type.value) if op.op_type == OpType.USER_INPUT: text = op.data.get("text", "") if op.data else "" await Handlers.run_agent(session, text) return True if op.op_type == OpType.COMPACT: await _compact_and_notify(session) return True if op.op_type == OpType.UNDO: await Handlers.undo(session) return True if op.op_type == OpType.EXEC_APPROVAL: approvals = op.data.get("approvals", []) if op.data else [] await Handlers.exec_approval(session, approvals) return True if op.op_type == OpType.SHUTDOWN: return not await Handlers.shutdown(session) logger.warning(f"Unknown operation: {op.op_type}") return True async def submission_loop( submission_queue: asyncio.Queue, event_queue: asyncio.Queue, config: Config | None = None, tool_router: ToolRouter | None = None, session_holder: list | None = None, hf_token: str | None = None, ) -> None: """ Main agent loop - processes submissions and dispatches to handlers. This is the core of the agent (like submission_loop in codex.rs:1259-1340) """ # Create session with tool router session = Session( event_queue, config=config, tool_router=tool_router, hf_token=hf_token ) if session_holder is not None: session_holder[0] = session logger.info("Agent loop started") # Retry any failed uploads from previous sessions (fire-and-forget) if config and config.save_sessions: Session.retry_failed_uploads_detached( directory="session_logs", repo_id=config.session_dataset_repo ) try: # Main processing loop async with tool_router: # Emit ready event after initialization await session.send_event( Event(event_type="ready", data={"message": "Agent initialized"}) ) while session.is_running: submission = await submission_queue.get() try: should_continue = await process_submission(session, submission) if not should_continue: break except asyncio.CancelledError: logger.warning("Agent loop cancelled") break except Exception as e: logger.error(f"Error in agent loop: {e}") await session.send_event( Event(event_type="error", data={"error": str(e)}) ) logger.info("Agent loop exited") finally: # Emergency save if session saving is enabled and shutdown wasn't called properly if session.config.save_sessions and session.is_running: logger.info("Emergency save: preserving session before exit...") try: local_path = session.save_and_upload_detached( session.config.session_dataset_repo ) if local_path: logger.info("Emergency save successful, upload in progress") except Exception as e: logger.error(f"Emergency save failed: {e}")