File size: 44,450 Bytes
246d201 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 |
import asyncio
import copy
import os
import traceback
from typing import Callable, ClassVar, Type
import litellm
from litellm.exceptions import (
BadRequestError,
ContextWindowExceededError,
RateLimitError,
)
from openhands.controller.agent import Agent
from openhands.controller.replay import ReplayManager
from openhands.controller.state.state import State, TrafficControlState
from openhands.controller.stuck import StuckDetector
from openhands.core.config import AgentConfig, LLMConfig
from openhands.core.exceptions import (
AgentStuckInLoopError,
FunctionCallNotExistsError,
FunctionCallValidationError,
LLMMalformedActionError,
LLMNoActionError,
LLMResponseError,
)
from openhands.core.logger import LOG_ALL_EVENTS
from openhands.core.logger import openhands_logger as logger
from openhands.core.schema import AgentState
from openhands.events import EventSource, EventStream, EventStreamSubscriber
from openhands.events.action import (
Action,
ActionConfirmationStatus,
AgentDelegateAction,
AgentFinishAction,
AgentRejectAction,
ChangeAgentStateAction,
CmdRunAction,
IPythonRunCellAction,
MessageAction,
NullAction,
)
from openhands.events.event import Event
from openhands.events.observation import (
AgentDelegateObservation,
AgentStateChangedObservation,
ErrorObservation,
NullObservation,
Observation,
)
from openhands.events.serialization.event import truncate_content
from openhands.llm.llm import LLM
# note: RESUME is only available on web GUI
TRAFFIC_CONTROL_REMINDER = (
"Please click on resume button if you'd like to continue, or start a new task."
)
class AgentController:
id: str
agent: Agent
max_iterations: int
event_stream: EventStream
state: State
confirmation_mode: bool
agent_to_llm_config: dict[str, LLMConfig]
agent_configs: dict[str, AgentConfig]
parent: 'AgentController | None' = None
delegate: 'AgentController | None' = None
_pending_action: Action | None = None
_closed: bool = False
filter_out: ClassVar[tuple[type[Event], ...]] = (
NullAction,
NullObservation,
ChangeAgentStateAction,
AgentStateChangedObservation,
)
def __init__(
self,
agent: Agent,
event_stream: EventStream,
max_iterations: int,
max_budget_per_task: float | None = None,
agent_to_llm_config: dict[str, LLMConfig] | None = None,
agent_configs: dict[str, AgentConfig] | None = None,
sid: str = 'default',
confirmation_mode: bool = False,
initial_state: State | None = None,
is_delegate: bool = False,
headless_mode: bool = True,
status_callback: Callable | None = None,
replay_events: list[Event] | None = None,
):
"""Initializes a new instance of the AgentController class.
Args:
agent: The agent instance to control.
event_stream: The event stream to publish events to.
max_iterations: The maximum number of iterations the agent can run.
max_budget_per_task: The maximum budget (in USD) allowed per task, beyond which the agent will stop.
agent_to_llm_config: A dictionary mapping agent names to LLM configurations in the case that
we delegate to a different agent.
agent_configs: A dictionary mapping agent names to agent configurations in the case that
we delegate to a different agent.
sid: The session ID of the agent.
confirmation_mode: Whether to enable confirmation mode for agent actions.
initial_state: The initial state of the controller.
is_delegate: Whether this controller is a delegate.
headless_mode: Whether the agent is run in headless mode.
status_callback: Optional callback function to handle status updates.
replay_events: A list of logs to replay.
"""
self.id = sid
self.agent = agent
self.headless_mode = headless_mode
self.is_delegate = is_delegate
# the event stream must be set before maybe subscribing to it
self.event_stream = event_stream
# subscribe to the event stream if this is not a delegate
if not self.is_delegate:
self.event_stream.subscribe(
EventStreamSubscriber.AGENT_CONTROLLER, self.on_event, self.id
)
# state from the previous session, state from a parent agent, or a fresh state
self.set_initial_state(
state=initial_state,
max_iterations=max_iterations,
confirmation_mode=confirmation_mode,
)
self.max_budget_per_task = max_budget_per_task
self.agent_to_llm_config = agent_to_llm_config if agent_to_llm_config else {}
self.agent_configs = agent_configs if agent_configs else {}
self._initial_max_iterations = max_iterations
self._initial_max_budget_per_task = max_budget_per_task
# stuck helper
self._stuck_detector = StuckDetector(self.state)
self.status_callback = status_callback
# replay-related
self._replay_manager = ReplayManager(replay_events)
async def close(self) -> None:
"""Closes the agent controller, canceling any ongoing tasks and unsubscribing from the event stream.
Note that it's fairly important that this closes properly, otherwise the state is incomplete.
"""
await self.set_agent_state_to(AgentState.STOPPED)
# we made history, now is the time to rewrite it!
# the final state.history will be used by external scripts like evals, tests, etc.
# history will need to be complete WITH delegates events
# like the regular agent history, it does not include:
# - 'hidden' events, events with hidden=True
# - backend events (the default 'filtered out' types, types in self.filter_out)
start_id = self.state.start_id if self.state.start_id >= 0 else 0
end_id = (
self.state.end_id
if self.state.end_id >= 0
else self.event_stream.get_latest_event_id()
)
self.state.history = list(
self.event_stream.get_events(
start_id=start_id,
end_id=end_id,
reverse=False,
filter_out_type=self.filter_out,
filter_hidden=True,
)
)
# unsubscribe from the event stream
# only the root parent controller subscribes to the event stream
if not self.is_delegate:
self.event_stream.unsubscribe(
EventStreamSubscriber.AGENT_CONTROLLER, self.id
)
self._closed = True
def log(self, level: str, message: str, extra: dict | None = None) -> None:
"""Logs a message to the agent controller's logger.
Args:
level (str): The logging level to use (e.g., 'info', 'debug', 'error').
message (str): The message to log.
extra (dict | None, optional): Additional fields to include in the log. Defaults to None.
"""
message = f'[Agent Controller {self.id}] {message}'
getattr(logger, level)(message, extra=extra, stacklevel=2)
def update_state_before_step(self):
self.state.iteration += 1
self.state.local_iteration += 1
async def update_state_after_step(self):
# update metrics especially for cost. Use deepcopy to avoid it being modified by agent._reset()
self.state.local_metrics = copy.deepcopy(self.agent.llm.metrics)
async def _react_to_exception(
self,
e: Exception,
):
"""React to an exception by setting the agent state to error and sending a status message."""
await self.set_agent_state_to(AgentState.ERROR)
if self.status_callback is not None:
err_id = ''
if isinstance(e, litellm.AuthenticationError):
err_id = 'STATUS$ERROR_LLM_AUTHENTICATION'
elif isinstance(e, RateLimitError):
await self.set_agent_state_to(AgentState.RATE_LIMITED)
return
self.status_callback('error', err_id, type(e).__name__ + ': ' + str(e))
def step(self):
asyncio.create_task(self._step_with_exception_handling())
async def _step_with_exception_handling(self):
try:
await self._step()
except Exception as e:
self.log(
'error',
f'Error while running the agent (session ID: {self.id}): {e}. '
f'Traceback: {traceback.format_exc()}',
)
reported = RuntimeError(
'There was an unexpected error while running the agent. Please '
f'report this error to the developers. Your session ID is {self.id}. '
f'Error type: {e.__class__.__name__}'
)
if isinstance(e, litellm.AuthenticationError) or isinstance(
e, litellm.BadRequestError
):
reported = e
await self._react_to_exception(reported)
def should_step(self, event: Event) -> bool:
"""
Whether the agent should take a step based on an event. In general,
the agent should take a step if it receives a message from the user,
or observes something in the environment (after acting).
"""
# it might be the delegate's day in the sun
if self.delegate is not None:
return False
if isinstance(event, Action):
if isinstance(event, MessageAction) and event.source == EventSource.USER:
return True
if (
isinstance(event, MessageAction)
and self.get_agent_state() != AgentState.AWAITING_USER_INPUT
):
# TODO: this is fragile, but how else to check if eligible?
return True
if isinstance(event, AgentDelegateAction):
return True
return False
if isinstance(event, Observation):
if isinstance(event, NullObservation) or isinstance(
event, AgentStateChangedObservation
):
return False
return True
return False
def on_event(self, event: Event) -> None:
"""Callback from the event stream. Notifies the controller of incoming events.
Args:
event (Event): The incoming event to process.
"""
# If we have a delegate that is not finished or errored, forward events to it
if self.delegate is not None:
delegate_state = self.delegate.get_agent_state()
if delegate_state not in (
AgentState.FINISHED,
AgentState.ERROR,
AgentState.REJECTED,
):
# Forward the event to delegate and skip parent processing
asyncio.get_event_loop().run_until_complete(
self.delegate._on_event(event)
)
return
else:
# delegate is done or errored, so end it
self.end_delegate()
return
# continue parent processing only if there's no active delegate
asyncio.get_event_loop().run_until_complete(self._on_event(event))
async def _on_event(self, event: Event) -> None:
if hasattr(event, 'hidden') and event.hidden:
return
# Give others a little chance
await asyncio.sleep(0.01)
# if the event is not filtered out, add it to the history
if not any(isinstance(event, filter_type) for filter_type in self.filter_out):
self.state.history.append(event)
if isinstance(event, Action):
await self._handle_action(event)
elif isinstance(event, Observation):
await self._handle_observation(event)
if self.should_step(event):
self.step()
async def _handle_action(self, action: Action) -> None:
"""Handles an Action from the agent or delegate."""
if isinstance(action, ChangeAgentStateAction):
await self.set_agent_state_to(action.agent_state) # type: ignore
elif isinstance(action, MessageAction):
await self._handle_message_action(action)
elif isinstance(action, AgentDelegateAction):
await self.start_delegate(action)
assert self.delegate is not None
# Post a MessageAction with the task for the delegate
if 'task' in action.inputs:
self.event_stream.add_event(
MessageAction(content='TASK: ' + action.inputs['task']),
EventSource.USER,
)
await self.delegate.set_agent_state_to(AgentState.RUNNING)
return
elif isinstance(action, AgentFinishAction):
self.state.outputs = action.outputs
self.state.metrics.merge(self.state.local_metrics)
await self.set_agent_state_to(AgentState.FINISHED)
elif isinstance(action, AgentRejectAction):
self.state.outputs = action.outputs
self.state.metrics.merge(self.state.local_metrics)
await self.set_agent_state_to(AgentState.REJECTED)
async def _handle_observation(self, observation: Observation) -> None:
"""Handles observation from the event stream.
Args:
observation (observation): The observation to handle.
"""
observation_to_print = copy.deepcopy(observation)
if len(observation_to_print.content) > self.agent.llm.config.max_message_chars:
observation_to_print.content = truncate_content(
observation_to_print.content, self.agent.llm.config.max_message_chars
)
# Use info level if LOG_ALL_EVENTS is set
log_level = 'info' if os.getenv('LOG_ALL_EVENTS') in ('true', '1') else 'debug'
self.log(
log_level, str(observation_to_print), extra={'msg_type': 'OBSERVATION'}
)
if observation.llm_metrics is not None:
self.agent.llm.metrics.merge(observation.llm_metrics)
if self._pending_action and self._pending_action.id == observation.cause:
if self.state.agent_state == AgentState.AWAITING_USER_CONFIRMATION:
return
self._pending_action = None
if self.state.agent_state == AgentState.USER_CONFIRMED:
await self.set_agent_state_to(AgentState.RUNNING)
if self.state.agent_state == AgentState.USER_REJECTED:
await self.set_agent_state_to(AgentState.AWAITING_USER_INPUT)
return
elif isinstance(observation, ErrorObservation):
if self.state.agent_state == AgentState.ERROR:
self.state.metrics.merge(self.state.local_metrics)
async def _handle_message_action(self, action: MessageAction) -> None:
"""Handles message actions from the event stream.
Args:
action (MessageAction): The message action to handle.
"""
if action.source == EventSource.USER:
# Use info level if LOG_ALL_EVENTS is set
log_level = (
'info' if os.getenv('LOG_ALL_EVENTS') in ('true', '1') else 'debug'
)
self.log(
log_level,
str(action),
extra={'msg_type': 'ACTION', 'event_source': EventSource.USER},
)
# Extend max iterations when the user sends a message (only in non-headless mode)
if self._initial_max_iterations is not None and not self.headless_mode:
self.state.max_iterations = (
self.state.iteration + self._initial_max_iterations
)
if (
self.state.traffic_control_state == TrafficControlState.THROTTLING
or self.state.traffic_control_state == TrafficControlState.PAUSED
):
self.state.traffic_control_state = TrafficControlState.NORMAL
self.log(
'debug',
f'Extended max iterations to {self.state.max_iterations} after user message',
)
if self.get_agent_state() != AgentState.RUNNING:
await self.set_agent_state_to(AgentState.RUNNING)
elif action.source == EventSource.AGENT and action.wait_for_response:
await self.set_agent_state_to(AgentState.AWAITING_USER_INPUT)
def _reset(self) -> None:
"""Resets the agent controller"""
# make sure there is an Observation with the tool call metadata to be recognized by the agent
# otherwise the pending action is found in history, but it's incomplete without an obs with tool result
if self._pending_action and hasattr(self._pending_action, 'tool_call_metadata'):
# find out if there already is an observation with the same tool call metadata
found_observation = False
for event in self.state.history:
if (
isinstance(event, Observation)
and event.tool_call_metadata
== self._pending_action.tool_call_metadata
):
found_observation = True
break
# make a new ErrorObservation with the tool call metadata
if not found_observation:
obs = ErrorObservation(content='The action has not been executed.')
obs.tool_call_metadata = self._pending_action.tool_call_metadata
obs._cause = self._pending_action.id # type: ignore[attr-defined]
self.event_stream.add_event(obs, EventSource.AGENT)
# reset the pending action, this will be called when the agent is STOPPED or ERROR
self._pending_action = None
self.agent.reset()
async def set_agent_state_to(self, new_state: AgentState) -> None:
"""Updates the agent's state and handles side effects. Can emit events to the event stream.
Args:
new_state (AgentState): The new state to set for the agent.
"""
self.log(
'info',
f'Setting agent({self.agent.name}) state from {self.state.agent_state} to {new_state}',
)
if new_state == self.state.agent_state:
return
if new_state in (AgentState.STOPPED, AgentState.ERROR):
# sync existing metrics BEFORE resetting the agent
await self.update_state_after_step()
self.state.metrics.merge(self.state.local_metrics)
self._reset()
elif (
new_state == AgentState.RUNNING
and self.state.agent_state == AgentState.PAUSED
# TODO: do we really need both THROTTLING and PAUSED states, or can we clean up one of them completely?
and self.state.traffic_control_state == TrafficControlState.THROTTLING
):
# user intends to interrupt traffic control and let the task resume temporarily
self.state.traffic_control_state = TrafficControlState.PAUSED
# User has chosen to deliberately continue - lets double the max iterations
if (
self.state.iteration is not None
and self.state.max_iterations is not None
and self._initial_max_iterations is not None
and not self.headless_mode
):
if self.state.iteration >= self.state.max_iterations:
self.state.max_iterations += self._initial_max_iterations
if (
self.state.metrics.accumulated_cost is not None
and self.max_budget_per_task is not None
and self._initial_max_budget_per_task is not None
):
if self.state.metrics.accumulated_cost >= self.max_budget_per_task:
self.max_budget_per_task += self._initial_max_budget_per_task
elif self._pending_action is not None and (
new_state in (AgentState.USER_CONFIRMED, AgentState.USER_REJECTED)
):
if hasattr(self._pending_action, 'thought'):
self._pending_action.thought = '' # type: ignore[union-attr]
if new_state == AgentState.USER_CONFIRMED:
confirmation_state = ActionConfirmationStatus.CONFIRMED
else:
confirmation_state = ActionConfirmationStatus.REJECTED
self._pending_action.confirmation_state = confirmation_state # type: ignore[attr-defined]
self._pending_action._id = None # type: ignore[attr-defined]
self.event_stream.add_event(self._pending_action, EventSource.AGENT)
self.state.agent_state = new_state
self.event_stream.add_event(
AgentStateChangedObservation('', self.state.agent_state),
EventSource.ENVIRONMENT,
)
if new_state == AgentState.INIT and self.state.resume_state:
await self.set_agent_state_to(self.state.resume_state)
self.state.resume_state = None
def get_agent_state(self) -> AgentState:
"""Returns the current state of the agent.
Returns:
AgentState: The current state of the agent.
"""
return self.state.agent_state
async def start_delegate(self, action: AgentDelegateAction) -> None:
"""Start a delegate agent to handle a subtask.
OpenHands is a multi-agentic system. A `task` is a conversation between
OpenHands (the whole system) and the user, which might involve one or more inputs
from the user. It starts with an initial input (typically a task statement) from
the user, and ends with either an `AgentFinishAction` initiated by the agent, a
stop initiated by the user, or an error.
A `subtask` is a conversation between an agent and the user, or another agent. If a `task`
is conducted by a single agent, then it's also a `subtask`. Otherwise, a `task` consists of
multiple `subtasks`, each executed by one agent.
Args:
action (AgentDelegateAction): The action containing information about the delegate agent to start.
"""
agent_cls: Type[Agent] = Agent.get_cls(action.agent)
agent_config = self.agent_configs.get(action.agent, self.agent.config)
llm_config = self.agent_to_llm_config.get(action.agent, self.agent.llm.config)
llm = LLM(config=llm_config)
delegate_agent = agent_cls(llm=llm, config=agent_config)
state = State(
inputs=action.inputs or {},
local_iteration=0,
iteration=self.state.iteration,
max_iterations=self.state.max_iterations,
delegate_level=self.state.delegate_level + 1,
# global metrics should be shared between parent and child
metrics=self.state.metrics,
# start on top of the stream
start_id=self.event_stream.get_latest_event_id() + 1,
)
self.log(
'debug',
f'start delegate, creating agent {delegate_agent.name} using LLM {llm}',
)
# Create the delegate with is_delegate=True so it does NOT subscribe directly
self.delegate = AgentController(
sid=self.id + '-delegate',
agent=delegate_agent,
event_stream=self.event_stream,
max_iterations=self.state.max_iterations,
max_budget_per_task=self.max_budget_per_task,
agent_to_llm_config=self.agent_to_llm_config,
agent_configs=self.agent_configs,
initial_state=state,
is_delegate=True,
headless_mode=self.headless_mode,
)
def end_delegate(self) -> None:
"""Ends the currently active delegate (e.g., if it is finished or errored)
so that this controller can resume normal operation.
"""
if self.delegate is None:
return
delegate_state = self.delegate.get_agent_state()
# update iteration that is shared across agents
self.state.iteration = self.delegate.state.iteration
# close the delegate controller before adding new events
asyncio.get_event_loop().run_until_complete(self.delegate.close())
if delegate_state in (AgentState.FINISHED, AgentState.REJECTED):
# retrieve delegate result
delegate_outputs = (
self.delegate.state.outputs if self.delegate.state else {}
)
# prepare delegate result observation
# TODO: replace this with AI-generated summary (#2395)
formatted_output = ', '.join(
f'{key}: {value}' for key, value in delegate_outputs.items()
)
content = (
f'{self.delegate.agent.name} finishes task with {formatted_output}'
)
# emit the delegate result observation
obs = AgentDelegateObservation(outputs=delegate_outputs, content=content)
self.event_stream.add_event(obs, EventSource.AGENT)
else:
# delegate state is ERROR
# emit AgentDelegateObservation with error content
delegate_outputs = (
self.delegate.state.outputs if self.delegate.state else {}
)
content = (
f'{self.delegate.agent.name} encountered an error during execution.'
)
# emit the delegate result observation
obs = AgentDelegateObservation(outputs=delegate_outputs, content=content)
self.event_stream.add_event(obs, EventSource.AGENT)
# unset delegate so parent can resume normal handling
self.delegate = None
self.delegateAction = None
async def _step(self) -> None:
"""Executes a single step of the parent or delegate agent. Detects stuck agents and limits on the number of iterations and the task budget."""
if self.get_agent_state() != AgentState.RUNNING:
return
if self._pending_action:
return
self.log(
'info',
f'LEVEL {self.state.delegate_level} LOCAL STEP {self.state.local_iteration} GLOBAL STEP {self.state.iteration}',
extra={'msg_type': 'STEP'},
)
stop_step = False
if self.state.iteration >= self.state.max_iterations:
stop_step = await self._handle_traffic_control(
'iteration', self.state.iteration, self.state.max_iterations
)
if self.max_budget_per_task is not None:
current_cost = self.state.metrics.accumulated_cost
if current_cost > self.max_budget_per_task:
stop_step = await self._handle_traffic_control(
'budget', current_cost, self.max_budget_per_task
)
if stop_step:
logger.warning('Stopping agent due to traffic control')
return
if self._is_stuck():
await self._react_to_exception(
AgentStuckInLoopError('Agent got stuck in a loop')
)
return
self.update_state_before_step()
action: Action = NullAction()
if self._replay_manager.should_replay():
# in replay mode, we don't let the agent to proceed
# instead, we replay the action from the replay trajectory
action = self._replay_manager.step()
else:
try:
action = self.agent.step(self.state)
if action is None:
raise LLMNoActionError('No action was returned')
except (
LLMMalformedActionError,
LLMNoActionError,
LLMResponseError,
FunctionCallValidationError,
FunctionCallNotExistsError,
) as e:
self.event_stream.add_event(
ErrorObservation(
content=str(e),
),
EventSource.AGENT,
)
return
except (ContextWindowExceededError, BadRequestError) as e:
# FIXME: this is a hack until a litellm fix is confirmed
# Check if this is a nested context window error
error_str = str(e).lower()
if (
'contextwindowexceedederror' in error_str
or 'prompt is too long' in error_str
or isinstance(e, ContextWindowExceededError)
):
# When context window is exceeded, keep roughly half of agent interactions
self.state.history = self._apply_conversation_window(
self.state.history
)
# Save the ID of the first event in our truncated history for future reloading
if self.state.history:
self.state.start_id = self.state.history[0].id
# Don't add error event - let the agent retry with reduced context
return
raise
if action.runnable:
if self.state.confirmation_mode and (
type(action) is CmdRunAction or type(action) is IPythonRunCellAction
):
action.confirmation_state = (
ActionConfirmationStatus.AWAITING_CONFIRMATION
)
self._pending_action = action
if not isinstance(action, NullAction):
if (
hasattr(action, 'confirmation_state')
and action.confirmation_state
== ActionConfirmationStatus.AWAITING_CONFIRMATION
):
await self.set_agent_state_to(AgentState.AWAITING_USER_CONFIRMATION)
self.event_stream.add_event(action, EventSource.AGENT)
await self.update_state_after_step()
log_level = 'info' if LOG_ALL_EVENTS else 'debug'
self.log(log_level, str(action), extra={'msg_type': 'ACTION'})
async def _handle_traffic_control(
self, limit_type: str, current_value: float, max_value: float
) -> bool:
"""Handles agent state after hitting the traffic control limit.
Args:
limit_type (str): The type of limit that was hit.
current_value (float): The current value of the limit.
max_value (float): The maximum value of the limit.
"""
stop_step = False
if self.state.traffic_control_state == TrafficControlState.PAUSED:
self.log(
'debug', 'Hitting traffic control, temporarily resume upon user request'
)
self.state.traffic_control_state = TrafficControlState.NORMAL
else:
self.state.traffic_control_state = TrafficControlState.THROTTLING
# Format values as integers for iterations, keep decimals for budget
if limit_type == 'iteration':
current_str = str(int(current_value))
max_str = str(int(max_value))
else:
current_str = f'{current_value:.2f}'
max_str = f'{max_value:.2f}'
if self.headless_mode:
e = RuntimeError(
f'Agent reached maximum {limit_type} in headless mode. '
f'Current {limit_type}: {current_str}, max {limit_type}: {max_str}'
)
await self._react_to_exception(e)
else:
e = RuntimeError(
f'Agent reached maximum {limit_type}. '
f'Current {limit_type}: {current_str}, max {limit_type}: {max_str}. '
)
# FIXME: this isn't really an exception--we should have a different path
await self._react_to_exception(e)
stop_step = True
return stop_step
def get_state(self) -> State:
"""Returns the current running state object.
Returns:
State: The current state object.
"""
return self.state
def set_initial_state(
self,
state: State | None,
max_iterations: int,
confirmation_mode: bool = False,
) -> None:
"""Sets the initial state for the agent, either from the previous session, or from a parent agent, or by creating a new one.
Args:
state: The state to initialize with, or None to create a new state.
max_iterations: The maximum number of iterations allowed for the task.
confirmation_mode: Whether to enable confirmation mode.
"""
# state can come from:
# - the previous session, in which case it has history
# - from a parent agent, in which case it has no history
# - None / a new state
# If state is None, we create a brand new state and still load the event stream so we can restore the history
if state is None:
self.state = State(
inputs={},
max_iterations=max_iterations,
confirmation_mode=confirmation_mode,
)
self.state.start_id = 0
self.log(
'debug',
f'AgentController {self.id} - created new state. start_id: {self.state.start_id}',
)
else:
self.state = state
if self.state.start_id <= -1:
self.state.start_id = 0
self.log(
'debug',
f'AgentController {self.id} initializing history from event {self.state.start_id}',
)
# Always load from the event stream to avoid losing history
self._init_history()
def _init_history(self) -> None:
"""Initializes the agent's history from the event stream.
The history is a list of events that:
- Excludes events of types listed in self.filter_out
- Excludes events with hidden=True attribute
- For delegate events (between AgentDelegateAction and AgentDelegateObservation):
- Excludes all events between the action and observation
- Includes the delegate action and observation themselves
The history is loaded in two parts if truncation_id is set:
1. First user message from start_id onwards
2. Rest of history from truncation_id to the end
Otherwise loads normally from start_id.
"""
# define range of events to fetch
# delegates start with a start_id and initially won't find any events
# otherwise we're restoring a previous session
start_id = self.state.start_id if self.state.start_id >= 0 else 0
end_id = (
self.state.end_id
if self.state.end_id >= 0
else self.event_stream.get_latest_event_id()
)
# sanity check
if start_id > end_id + 1:
self.log(
'warning',
f'start_id {start_id} is greater than end_id + 1 ({end_id + 1}). History will be empty.',
)
self.state.history = []
return
events: list[Event] = []
# If we have a truncation point, get first user message and then rest of history
if hasattr(self.state, 'truncation_id') and self.state.truncation_id > 0:
# Find first user message from stream
first_user_msg = next(
(
e
for e in self.event_stream.get_events(
start_id=start_id,
end_id=end_id,
reverse=False,
filter_out_type=self.filter_out,
filter_hidden=True,
)
if isinstance(e, MessageAction) and e.source == EventSource.USER
),
None,
)
if first_user_msg:
events.append(first_user_msg)
# the rest of the events are from the truncation point
start_id = self.state.truncation_id
# Get rest of history
events_to_add = list(
self.event_stream.get_events(
start_id=start_id,
end_id=end_id,
reverse=False,
filter_out_type=self.filter_out,
filter_hidden=True,
)
)
events.extend(events_to_add)
# Find all delegate action/observation pairs
delegate_ranges: list[tuple[int, int]] = []
delegate_action_ids: list[int] = [] # stack of unmatched delegate action IDs
for event in events:
if isinstance(event, AgentDelegateAction):
delegate_action_ids.append(event.id)
# Note: we can get agent=event.agent and task=event.inputs.get('task','')
# if we need to track these in the future
elif isinstance(event, AgentDelegateObservation):
# Match with most recent unmatched delegate action
if not delegate_action_ids:
self.log(
'warning',
f'Found AgentDelegateObservation without matching action at id={event.id}',
)
continue
action_id = delegate_action_ids.pop()
delegate_ranges.append((action_id, event.id))
# Filter out events between delegate action/observation pairs
if delegate_ranges:
filtered_events: list[Event] = []
current_idx = 0
for start_id, end_id in sorted(delegate_ranges):
# Add events before delegate range
filtered_events.extend(
event for event in events[current_idx:] if event.id < start_id
)
# Add delegate action and observation
filtered_events.extend(
event for event in events if event.id in (start_id, end_id)
)
# Update index to after delegate range
current_idx = next(
(i for i, e in enumerate(events) if e.id > end_id), len(events)
)
# Add any remaining events after last delegate range
filtered_events.extend(events[current_idx:])
self.state.history = filtered_events
else:
self.state.history = events
# make sure history is in sync
self.state.start_id = start_id
def _apply_conversation_window(self, events: list[Event]) -> list[Event]:
"""Cuts history roughly in half when context window is exceeded, preserving action-observation pairs
and ensuring the first user message is always included.
The algorithm:
1. Cut history in half
2. Check first event in new history:
- If Observation: find and include its Action
- If MessageAction: ensure its related Action-Observation pair isn't split
3. Always include the first user message
Args:
events: List of events to filter
Returns:
Filtered list of events keeping newest half while preserving pairs
"""
if not events:
return events
# Find first user message - we'll need to ensure it's included
first_user_msg = next(
(
e
for e in events
if isinstance(e, MessageAction) and e.source == EventSource.USER
),
None,
)
# cut in half
mid_point = max(1, len(events) // 2)
kept_events = events[mid_point:]
# Handle first event in truncated history
if kept_events:
i = 0
while i < len(kept_events):
first_event = kept_events[i]
if isinstance(first_event, Observation) and first_event.cause:
# Find its action and include it
matching_action = next(
(
e
for e in reversed(events[:mid_point])
if isinstance(e, Action) and e.id == first_event.cause
),
None,
)
if matching_action:
kept_events = [matching_action] + kept_events
else:
self.log(
'warning',
f'Found Observation without matching Action at id={first_event.id}',
)
# drop this observation
kept_events = kept_events[1:]
break
elif isinstance(first_event, MessageAction) or (
isinstance(first_event, Action)
and first_event.source == EventSource.USER
):
# if it's a message action or a user action, keep it and continue to find the next event
i += 1
continue
else:
# if it's an action with source == EventSource.AGENT, we're good
break
# Save where to continue from in next reload
if kept_events:
self.state.truncation_id = kept_events[0].id
# Ensure first user message is included
if first_user_msg and first_user_msg not in kept_events:
kept_events = [first_user_msg] + kept_events
# start_id points to first user message
if first_user_msg:
self.state.start_id = first_user_msg.id
return kept_events
def _is_stuck(self) -> bool:
"""Checks if the agent or its delegate is stuck in a loop.
Returns:
bool: True if the agent is stuck, False otherwise.
"""
# check if delegate stuck
if self.delegate and self.delegate._is_stuck():
return True
return self._stuck_detector.is_stuck(self.headless_mode)
def __repr__(self):
return (
f'AgentController(id={getattr(self, "id", "<uninitialized>")}, '
f'agent={getattr(self, "agent", "<uninitialized>")!r}, '
f'event_stream={getattr(self, "event_stream", "<uninitialized>")!r}, '
f'state={getattr(self, "state", "<uninitialized>")!r}, '
f'delegate={getattr(self, "delegate", "<uninitialized>")!r}, '
f'_pending_action={getattr(self, "_pending_action", "<uninitialized>")!r})'
)
def _is_awaiting_observation(self):
events = self.event_stream.get_events(reverse=True)
for event in events:
if isinstance(event, AgentStateChangedObservation):
result = event.agent_state == AgentState.RUNNING
return result
return False
|