Files
strix/strix/core/agents.py
T

537 lines
21 KiB
Python

"""SDK-native state for Strix's addressable agent graph."""
from __future__ import annotations
import asyncio
import json
import logging
import tempfile
from dataclasses import dataclass, field
from pathlib import Path
from typing import TYPE_CHECKING, Any, Literal, cast
from strix.core.sessions import session_write_lock
if TYPE_CHECKING:
from collections.abc import Callable
from agents.items import TResponseInputItem
from agents.memory import Session
logger = logging.getLogger(__name__)
Status = Literal["running", "waiting", "completed", "stopped", "crashed", "failed", "budget_paused"]
# Why an agent parked. The user can message any agent, so this - not the agent's
# position in the tree - decides whether waiting is bounded: only an agent waiting
# on other agents is re-checked on a timer.
WaitKind = Literal["user", "agents", "stalled"]
@dataclass(slots=True)
class AgentRuntime:
session: Session | None = None
task: asyncio.Task[Any] | None = None
stream: Any | None = None
interrupt_on_message: bool = False
wake: asyncio.Event = field(default_factory=asyncio.Event)
mailbox: list[dict[str, Any]] = field(default_factory=list)
user_wake_required: bool = False
class AgentCoordinator:
"""Single owner for graph state, SDK runtimes, messages, and resume snapshots."""
def __init__(self) -> None:
self.statuses: dict[str, Status] = {}
self.parent_of: dict[str, str | None] = {}
self.names: dict[str, str] = {}
self.metadata: dict[str, dict[str, Any]] = {}
self.pending_counts: dict[str, int] = {}
self.errors: dict[str, str] = {}
self.recovery_counts: dict[str, int] = {}
self.idle_resume_counts: dict[str, int] = {}
self.wait_kinds: dict[str, WaitKind] = {}
self.runtimes: dict[str, AgentRuntime] = {}
self._parent_notified: set[str] = set()
self._lock = asyncio.Lock()
self._snapshot_path: Path | None = None
self.is_shutting_down = False
self._budget_stopped = False
self._reserve_stopped = False
self._budget_paused = False
self._extend_budget: Callable[[], None] | None = None
def set_snapshot_path(self, path: Path) -> None:
self._snapshot_path = path
def mark_shutting_down(self) -> None:
self.is_shutting_down = True
@property
def budget_stopped(self) -> bool:
return self._budget_stopped
async def trigger_budget_stop(self) -> None:
"""Signal a scan-wide budget stop and wake every parked agent so it exits."""
async with self._lock:
self._budget_stopped = True
for runtime in self.runtimes.values():
runtime.wake.set()
@property
def reserve_stopped(self) -> bool:
return self._reserve_stopped
@property
def budget_paused(self) -> bool:
return self._budget_paused
def set_budget_extender(self, extend: Callable[[], None]) -> None:
self._extend_budget = extend
async def pause_for_budget(self, agent_id: str) -> None:
async with self._lock:
self._budget_paused = True
await self.set_status(agent_id, "budget_paused")
async def resume_from_budget_pause(self, *, exclude: str | None = None) -> None:
async with self._lock:
if not self._budget_paused:
return
self._budget_paused = False
paused = [aid for aid, status in self.statuses.items() if status == "budget_paused"]
if self._extend_budget is not None:
self._extend_budget()
for aid in paused:
await self.set_status(aid, "waiting")
if aid != exclude:
await self.send(
aid,
{
"from": "system",
"type": "budget_extended",
"content": (
"[Budget] The user extended the scan budget \u2014 continue your "
"current task."
),
},
)
async def reset_budget_stops(
self,
*,
budget_stopped: bool,
reserve_stopped: bool,
budget_paused: bool = False,
) -> None:
async with self._lock:
self._budget_stopped = budget_stopped
self._reserve_stopped = reserve_stopped
if not budget_paused:
self._budget_paused = False
for aid, status in self.statuses.items():
if status == "budget_paused":
self.statuses[aid] = "waiting"
await self._maybe_snapshot()
async def claim_reserve_notification(self) -> str | None:
async with self._lock:
if self._reserve_stopped:
return None
self._reserve_stopped = True
for runtime in self.runtimes.values():
runtime.wake.set()
return next((aid for aid, parent in self.parent_of.items() if parent is None), None)
async def register(
self,
agent_id: str,
name: str,
parent_id: str | None,
*,
task: str | None = None,
skills: list[str] | None = None,
) -> None:
async with self._lock:
self.statuses[agent_id] = "running"
self.parent_of[agent_id] = parent_id
self.names[agent_id] = name
self.pending_counts.setdefault(agent_id, 0)
self.metadata[agent_id] = {
"task": task or "",
"skills": list(skills or []),
}
self.runtimes.setdefault(agent_id, AgentRuntime())
logger.info("agent.register %s (%s) parent=%s", agent_id, name, parent_id or "-")
await self._maybe_snapshot()
async def attach_runtime(
self,
agent_id: str,
*,
session: Session | None = None,
task: asyncio.Task[Any] | None = None,
interrupt_on_message: bool | None = None,
) -> None:
async with self._lock:
runtime = self.runtimes.setdefault(agent_id, AgentRuntime())
if session is not None:
runtime.session = session
if task is not None:
runtime.task = task
if interrupt_on_message is not None:
runtime.interrupt_on_message = interrupt_on_message
async def mark_running(self, agent_id: str) -> None:
async with self._lock:
if agent_id in self.statuses:
self.statuses[agent_id] = "running"
self.errors.pop(agent_id, None)
self.wait_kinds.pop(agent_id, None)
self.runtimes.setdefault(agent_id, AgentRuntime()).user_wake_required = False
self._parent_notified.discard(agent_id)
await self._maybe_snapshot()
async def park_waiting(self, agent_id: str, *, wait_kind: WaitKind) -> None:
"""Park an agent, recording what it is waiting on so the driver can time it."""
async with self._lock:
if agent_id in self.statuses:
self.wait_kinds[agent_id] = wait_kind
await self.set_status(agent_id, "waiting")
async def wait_kind_of(self, agent_id: str) -> WaitKind | None:
async with self._lock:
return self.wait_kinds.get(agent_id)
async def record_recovery(self, agent_id: str) -> int:
"""Count a turn that ended without a lifecycle tool call; return the new total.
Persisted so a resumed agent cannot earn a fresh nudge budget on every
auto-resume and loop forever.
"""
async with self._lock:
count = self.recovery_counts.get(agent_id, 0) + 1
self.recovery_counts[agent_id] = count
await self._maybe_snapshot()
return count
async def reset_recovery(self, agent_id: str) -> None:
"""Clear the nudge budget after real progress (new message or a lifecycle tool)."""
async with self._lock:
if self.recovery_counts.pop(agent_id, None) is None:
return
await self._maybe_snapshot()
async def record_idle_resume(self, agent_id: str) -> int:
"""Count an auto-resume that no message triggered; return the new total.
An agent that parks again after every auto-resume would otherwise burn a
model turn per timeout for the rest of the scan.
"""
async with self._lock:
count = self.idle_resume_counts.get(agent_id, 0) + 1
self.idle_resume_counts[agent_id] = count
await self._maybe_snapshot()
return count
async def reset_idle_resumes(self, agent_id: str) -> None:
async with self._lock:
if self.idle_resume_counts.pop(agent_id, None) is None:
return
await self._maybe_snapshot()
async def set_status(
self, agent_id: str, status: Status | str, *, error: str | None = None
) -> None:
async with self._lock:
if agent_id not in self.statuses:
return
self.statuses[agent_id] = status # type: ignore[assignment]
if error is not None:
self.errors[agent_id] = error
elif status == "running":
self.errors.pop(agent_id, None)
if status == "running":
# Running again means a fresh stint that owes its parent its own notice.
self._parent_notified.discard(agent_id)
runtime = self.runtimes.setdefault(agent_id, AgentRuntime())
runtime.user_wake_required = status in {"failed", "crashed"}
runtime.wake.set()
logger.info("agent.status %s=%s", agent_id, status)
await self._maybe_snapshot()
async def claim_parent_notice(self, agent_id: str) -> bool:
"""Reserve the one notice a child owes its parent when it stops running.
A completion report and a terminal notice carry the same information, so
whichever comes first claims the slot and the other is skipped.
"""
async with self._lock:
if agent_id in self._parent_notified:
return False
self._parent_notified.add(agent_id)
return True
async def send(
self, target_agent_id: str, message: dict[str, Any], *, interrupt: bool = True
) -> bool:
"""Queue a user/peer message in the target's mailbox and wake it."""
from_user = message.get("from") == "user"
if from_user and self._budget_paused:
await self.resume_from_budget_pause(exclude=target_agent_id)
async with self._lock:
if target_agent_id not in self.statuses:
logger.debug("agent.send dropped unknown target=%s", target_agent_id)
return False
runtime = self.runtimes.setdefault(target_agent_id, AgentRuntime())
runtime.mailbox.append(dict(message))
self.pending_counts[target_agent_id] = self.pending_counts.get(target_agent_id, 0) + 1
if from_user:
runtime.user_wake_required = False
runtime.wake.set()
stream = runtime.stream
interrupt_on_message = runtime.interrupt_on_message
if stream is not None and interrupt and interrupt_on_message:
stream.cancel(mode="immediate")
await self._maybe_snapshot()
return True
async def wait_for_message(self, agent_id: str, *, timeout: float | None = None) -> bool:
"""Wait until a message is ready for ``agent_id``; False on ``timeout``."""
while True:
async with self._lock:
runtime = self.runtimes.setdefault(agent_id, AgentRuntime())
reserve_exit = self._reserve_stopped and self.parent_of.get(agent_id) is not None
pending_ready = (
self.pending_counts.get(agent_id, 0) > 0 and not runtime.user_wake_required
)
if self._budget_stopped or reserve_exit or pending_ready:
return True
wake = runtime.wake
wake.clear()
if timeout is None:
await wake.wait()
else:
try:
await asyncio.wait_for(wake.wait(), timeout)
except TimeoutError:
return False
async def consume_pending(
self,
agent_id: str,
*,
include_items: bool = False,
) -> tuple[int, list[Any]]:
"""Drain the agent's mailbox into its own SDK session."""
async with self._lock:
runtime = self.runtimes.setdefault(agent_id, AgentRuntime())
queued = list(runtime.mailbox)
runtime.mailbox.clear()
count = max(self.pending_counts.get(agent_id, 0), len(queued))
self.pending_counts[agent_id] = 0
session = runtime.session
if count <= 0:
return 0, []
items = [self._message_to_session_item(m) for m in queued]
if items:
if session is None:
logger.warning(
"agent %s has no SDK session attached; %d queued messages were not persisted",
agent_id,
len(items),
)
else:
try:
async with session_write_lock(session):
await session.add_items(items)
except Exception:
logger.exception(
"failed to append %d queued messages to the session of %s",
len(items),
agent_id,
)
await self._maybe_snapshot()
if not include_items:
return count, []
return count, items
async def request_stop(self, agent_id: str) -> None:
async with self._lock:
if agent_id not in self.statuses:
return
self.statuses[agent_id] = "stopped"
runtime = self.runtimes.setdefault(agent_id, AgentRuntime())
runtime.wake.set()
stream = runtime.stream
if stream is not None:
stream.cancel(mode="after_turn")
await self._maybe_snapshot()
async def cancel_descendants(self, agent_id: str) -> None:
tasks = []
async with self._lock:
for aid in reversed(self._subtree_order_locked(agent_id)):
task = self.runtimes.get(aid, AgentRuntime()).task
if task is not None and not task.done():
tasks.append(task)
for task in tasks:
task.cancel()
if tasks:
await asyncio.gather(*tasks, return_exceptions=True)
async def cancel_descendants_graceful(self, agent_id: str) -> list[str]:
"""Stop a subtree leaves-first and report which agents were stopped."""
async with self._lock:
order = self._subtree_order_locked(agent_id)
stopped = list(reversed(order))
for aid in stopped:
await self.request_stop(aid)
await self._maybe_snapshot()
return stopped
async def attach_stream(
self,
agent_id: str,
stream: Any,
) -> None:
async with self._lock:
self.runtimes.setdefault(agent_id, AgentRuntime()).stream = stream
async def detach_stream(
self,
agent_id: str,
stream: Any,
) -> None:
async with self._lock:
runtime = self.runtimes.setdefault(agent_id, AgentRuntime())
if runtime.stream is stream:
runtime.stream = None
async def active_agents_except(self, agent_id: str) -> list[dict[str, Any]]:
async with self._lock:
return [
{
"agent_id": aid,
"name": self.names.get(aid, aid),
"status": status,
"parent_id": self.parent_of.get(aid),
}
for aid, status in self.statuses.items()
if aid != agent_id and status in {"running", "waiting"}
]
async def graph_snapshot(
self,
) -> tuple[dict[str, str | None], dict[str, Status], dict[str, str], dict[str, str]]:
async with self._lock:
return (
dict(self.parent_of),
dict(self.statuses),
dict(self.names),
dict(self.errors),
)
def _message_to_session_item(self, message: dict[str, Any]) -> TResponseInputItem:
sender = str(message.get("from", "unknown"))
content = str(message.get("content", ""))
if sender == "user":
return cast("TResponseInputItem", {"role": "user", "content": content})
sender_name = self.names.get(sender, sender)
msg_type = message.get("type", "information")
priority = message.get("priority", "normal")
return cast(
"TResponseInputItem",
{
"role": "user",
"content": (
f"[Message from {sender_name} ({sender}) | type={msg_type} "
f"| priority={priority}]\n{content}"
),
},
)
def _subtree_order_locked(self, agent_id: str) -> list[str]:
queue = [agent_id]
order: list[str] = []
while queue:
aid = queue.pop()
order.append(aid)
queue.extend(child for child, parent in self.parent_of.items() if parent == aid)
return order
async def snapshot(self) -> dict[str, Any]:
async with self._lock:
return {
"statuses": dict(self.statuses),
"parent_of": dict(self.parent_of),
"names": dict(self.names),
"metadata": {aid: dict(md) for aid, md in self.metadata.items()},
"pending_counts": dict(self.pending_counts),
"recovery_counts": dict(self.recovery_counts),
"idle_resume_counts": dict(self.idle_resume_counts),
"wait_kinds": dict(self.wait_kinds),
"mailboxes": {
aid: [dict(m) for m in runtime.mailbox]
for aid, runtime in self.runtimes.items()
if runtime.mailbox
},
"errors": dict(self.errors),
"budget_stopped": self._budget_stopped,
"reserve_stopped": self._reserve_stopped,
"budget_paused": self._budget_paused,
}
async def restore(self, snap: dict[str, Any]) -> None:
async with self._lock:
self.statuses = dict(snap.get("statuses", {}))
self.parent_of = dict(snap.get("parent_of", {}))
self.names = dict(snap.get("names", {}))
self.metadata = {aid: dict(md) for aid, md in snap.get("metadata", {}).items()}
self.pending_counts = dict(snap.get("pending_counts", {}))
self.errors = dict(snap.get("errors", {}))
self.recovery_counts = dict(snap.get("recovery_counts", {}))
self.idle_resume_counts = dict(snap.get("idle_resume_counts", {}))
self.wait_kinds = dict(snap.get("wait_kinds", {}))
mailboxes = snap.get("mailboxes", {})
if isinstance(mailboxes, dict):
for aid, msgs in mailboxes.items():
if isinstance(msgs, list):
runtime = self.runtimes.setdefault(aid, AgentRuntime())
runtime.mailbox = [dict(m) for m in msgs if isinstance(m, dict)]
self._budget_stopped = bool(snap.get("budget_stopped", False))
self._reserve_stopped = bool(snap.get("reserve_stopped", False))
self._budget_paused = bool(snap.get("budget_paused", False))
for aid in self.statuses:
self.runtimes.setdefault(aid, AgentRuntime())
async def _maybe_snapshot(self) -> None:
path = self._snapshot_path
if path is None:
return
try:
data = await self.snapshot()
payload = json.dumps(data, ensure_ascii=False, default=str)
path.parent.mkdir(parents=True, exist_ok=True)
with tempfile.NamedTemporaryFile(
mode="w",
encoding="utf-8",
dir=str(path.parent),
prefix=f".{path.name}.",
suffix=".tmp",
delete=False,
) as tmp:
tmp.write(payload)
tmp_path = Path(tmp.name)
tmp_path.replace(path)
except Exception:
logger.exception("coordinator snapshot to %s failed", path)
def coordinator_from_context(ctx: dict[str, Any]) -> AgentCoordinator | None:
coordinator = ctx.get("coordinator")
return coordinator if isinstance(coordinator, AgentCoordinator) else None