483 lines
21 KiB
Python
483 lines
21 KiB
Python
"""Agent loop: the core processing engine."""
|
|
|
|
from __future__ import annotations
|
|
|
|
import asyncio
|
|
import json
|
|
import re
|
|
from contextlib import AsyncExitStack
|
|
from pathlib import Path
|
|
from typing import TYPE_CHECKING, Any, Awaitable, Callable
|
|
|
|
from loguru import logger
|
|
|
|
from nanobot.agent.context import ContextBuilder
|
|
from nanobot.agent.memory import MemoryStore
|
|
from nanobot.agent.subagent import SubagentManager
|
|
from nanobot.agent.tools.cron import CronTool
|
|
from nanobot.agent.tools.filesystem import EditFileTool, ListDirTool, ReadFileTool, WriteFileTool
|
|
from nanobot.agent.tools.message import MessageTool
|
|
from nanobot.agent.tools.registry import ToolRegistry
|
|
from nanobot.agent.tools.shell import ExecTool
|
|
from nanobot.agent.tools.spawn import SpawnTool
|
|
from nanobot.agent.tools.web import WebFetchTool, WebSearchTool
|
|
from nanobot.bus.events import InboundMessage, OutboundMessage
|
|
from nanobot.bus.queue import MessageBus
|
|
from nanobot.providers.base import LLMProvider
|
|
from nanobot.session.manager import Session, SessionManager
|
|
|
|
if TYPE_CHECKING:
|
|
from nanobot.config.schema import ChannelsConfig, ExecToolConfig
|
|
from nanobot.cron.service import CronService
|
|
|
|
|
|
class AgentLoop:
|
|
"""
|
|
The agent loop is the core processing engine.
|
|
|
|
It:
|
|
1. Receives messages from the bus
|
|
2. Builds context with history, memory, skills
|
|
3. Calls the LLM
|
|
4. Executes tool calls
|
|
5. Sends responses back
|
|
"""
|
|
|
|
_TOOL_RESULT_MAX_CHARS = 500
|
|
|
|
def __init__(
|
|
self,
|
|
bus: MessageBus,
|
|
provider: LLMProvider,
|
|
workspace: Path,
|
|
model: str | None = None,
|
|
max_iterations: int = 40,
|
|
temperature: float = 0.1,
|
|
max_tokens: int = 4096,
|
|
memory_window: int = 100,
|
|
brave_api_key: str | None = None,
|
|
exec_config: ExecToolConfig | None = None,
|
|
cron_service: CronService | None = None,
|
|
restrict_to_workspace: bool = False,
|
|
session_manager: SessionManager | None = None,
|
|
mcp_servers: dict | None = None,
|
|
channels_config: ChannelsConfig | None = None,
|
|
):
|
|
from nanobot.config.schema import ExecToolConfig
|
|
self.bus = bus
|
|
self.channels_config = channels_config
|
|
self.provider = provider
|
|
self.workspace = workspace
|
|
self.model = model or provider.get_default_model()
|
|
self.max_iterations = max_iterations
|
|
self.temperature = temperature
|
|
self.max_tokens = max_tokens
|
|
self.memory_window = memory_window
|
|
self.brave_api_key = brave_api_key
|
|
self.exec_config = exec_config or ExecToolConfig()
|
|
self.cron_service = cron_service
|
|
self.restrict_to_workspace = restrict_to_workspace
|
|
|
|
self.context = ContextBuilder(workspace)
|
|
self.sessions = session_manager or SessionManager(workspace)
|
|
self.tools = ToolRegistry()
|
|
self.subagents = SubagentManager(
|
|
provider=provider,
|
|
workspace=workspace,
|
|
bus=bus,
|
|
model=self.model,
|
|
temperature=self.temperature,
|
|
max_tokens=self.max_tokens,
|
|
brave_api_key=brave_api_key,
|
|
exec_config=self.exec_config,
|
|
restrict_to_workspace=restrict_to_workspace,
|
|
)
|
|
|
|
self._running = False
|
|
self._mcp_servers = mcp_servers or {}
|
|
self._mcp_stack: AsyncExitStack | None = None
|
|
self._mcp_connected = False
|
|
self._mcp_connecting = False
|
|
self._consolidating: set[str] = set() # Session keys with consolidation in progress
|
|
self._consolidation_tasks: set[asyncio.Task] = set() # Strong refs to in-flight tasks
|
|
self._consolidation_locks: dict[str, asyncio.Lock] = {}
|
|
self._active_tasks: dict[str, list[asyncio.Task]] = {} # session_key -> tasks
|
|
self._processing_lock = asyncio.Lock()
|
|
self._register_default_tools()
|
|
|
|
def _register_default_tools(self) -> None:
|
|
"""Register the default set of tools."""
|
|
allowed_dir = self.workspace if self.restrict_to_workspace else None
|
|
for cls in (ReadFileTool, WriteFileTool, EditFileTool, ListDirTool):
|
|
self.tools.register(cls(workspace=self.workspace, allowed_dir=allowed_dir))
|
|
self.tools.register(ExecTool(
|
|
working_dir=str(self.workspace),
|
|
timeout=self.exec_config.timeout,
|
|
restrict_to_workspace=self.restrict_to_workspace,
|
|
path_append=self.exec_config.path_append,
|
|
))
|
|
self.tools.register(WebSearchTool(api_key=self.brave_api_key))
|
|
self.tools.register(WebFetchTool())
|
|
self.tools.register(MessageTool(send_callback=self.bus.publish_outbound))
|
|
self.tools.register(SpawnTool(manager=self.subagents))
|
|
if self.cron_service:
|
|
self.tools.register(CronTool(self.cron_service))
|
|
|
|
async def _connect_mcp(self) -> None:
|
|
"""Connect to configured MCP servers (one-time, lazy)."""
|
|
if self._mcp_connected or self._mcp_connecting or not self._mcp_servers:
|
|
return
|
|
self._mcp_connecting = True
|
|
from nanobot.agent.tools.mcp import connect_mcp_servers
|
|
try:
|
|
self._mcp_stack = AsyncExitStack()
|
|
await self._mcp_stack.__aenter__()
|
|
await connect_mcp_servers(self._mcp_servers, self.tools, self._mcp_stack)
|
|
self._mcp_connected = True
|
|
except Exception as e:
|
|
logger.error("Failed to connect MCP servers (will retry next message): {}", e)
|
|
if self._mcp_stack:
|
|
try:
|
|
await self._mcp_stack.aclose()
|
|
except Exception:
|
|
pass
|
|
self._mcp_stack = None
|
|
finally:
|
|
self._mcp_connecting = False
|
|
|
|
def _set_tool_context(self, channel: str, chat_id: str, message_id: str | None = None) -> None:
|
|
"""Update context for all tools that need routing info."""
|
|
for name in ("message", "spawn", "cron"):
|
|
if tool := self.tools.get(name):
|
|
if hasattr(tool, "set_context"):
|
|
tool.set_context(channel, chat_id, *([message_id] if name == "message" else []))
|
|
|
|
@staticmethod
|
|
def _strip_think(text: str | None) -> str | None:
|
|
"""Remove <think>…</think> blocks that some models embed in content."""
|
|
if not text:
|
|
return None
|
|
return re.sub(r"<think>[\s\S]*?</think>", "", text).strip() or None
|
|
|
|
@staticmethod
|
|
def _tool_hint(tool_calls: list) -> str:
|
|
"""Format tool calls as concise hint, e.g. 'web_search("query")'."""
|
|
def _fmt(tc):
|
|
val = next(iter(tc.arguments.values()), None) if tc.arguments else None
|
|
if not isinstance(val, str):
|
|
return tc.name
|
|
return f'{tc.name}("{val[:40]}…")' if len(val) > 40 else f'{tc.name}("{val}")'
|
|
return ", ".join(_fmt(tc) for tc in tool_calls)
|
|
|
|
async def _run_agent_loop(
|
|
self,
|
|
initial_messages: list[dict],
|
|
on_progress: Callable[..., Awaitable[None]] | None = None,
|
|
) -> tuple[str | None, list[str], list[dict]]:
|
|
"""Run the agent iteration loop. Returns (final_content, tools_used, messages)."""
|
|
messages = initial_messages
|
|
iteration = 0
|
|
final_content = None
|
|
tools_used: list[str] = []
|
|
|
|
while iteration < self.max_iterations:
|
|
iteration += 1
|
|
|
|
response = await self.provider.chat(
|
|
messages=messages,
|
|
tools=self.tools.get_definitions(),
|
|
model=self.model,
|
|
temperature=self.temperature,
|
|
max_tokens=self.max_tokens,
|
|
)
|
|
|
|
if response.has_tool_calls:
|
|
if on_progress:
|
|
clean = self._strip_think(response.content)
|
|
if clean:
|
|
await on_progress(clean)
|
|
await on_progress(self._tool_hint(response.tool_calls), tool_hint=True)
|
|
|
|
tool_call_dicts = [
|
|
{
|
|
"id": tc.id,
|
|
"type": "function",
|
|
"function": {
|
|
"name": tc.name,
|
|
"arguments": json.dumps(tc.arguments, ensure_ascii=False)
|
|
}
|
|
}
|
|
for tc in response.tool_calls
|
|
]
|
|
messages = self.context.add_assistant_message(
|
|
messages, response.content, tool_call_dicts,
|
|
reasoning_content=response.reasoning_content,
|
|
)
|
|
|
|
for tool_call in response.tool_calls:
|
|
tools_used.append(tool_call.name)
|
|
args_str = json.dumps(tool_call.arguments, ensure_ascii=False)
|
|
logger.info("Tool call: {}({})", tool_call.name, args_str[:200])
|
|
result = await self.tools.execute(tool_call.name, tool_call.arguments)
|
|
messages = self.context.add_tool_result(
|
|
messages, tool_call.id, tool_call.name, result
|
|
)
|
|
else:
|
|
clean = self._strip_think(response.content)
|
|
messages = self.context.add_assistant_message(
|
|
messages, clean, reasoning_content=response.reasoning_content,
|
|
)
|
|
final_content = clean
|
|
break
|
|
|
|
if final_content is None and iteration >= self.max_iterations:
|
|
logger.warning("Max iterations ({}) reached", self.max_iterations)
|
|
final_content = (
|
|
f"I reached the maximum number of tool call iterations ({self.max_iterations}) "
|
|
"without completing the task. You can try breaking the task into smaller steps."
|
|
)
|
|
|
|
return final_content, tools_used, messages
|
|
|
|
async def run(self) -> None:
|
|
"""Run the agent loop, dispatching messages as tasks to stay responsive to /stop."""
|
|
self._running = True
|
|
await self._connect_mcp()
|
|
logger.info("Agent loop started")
|
|
|
|
while self._running:
|
|
try:
|
|
msg = await asyncio.wait_for(self.bus.consume_inbound(), timeout=1.0)
|
|
except asyncio.TimeoutError:
|
|
continue
|
|
|
|
if msg.content.strip().lower() == "/stop":
|
|
await self._handle_stop(msg)
|
|
else:
|
|
task = asyncio.create_task(self._dispatch(msg))
|
|
self._active_tasks.setdefault(msg.session_key, []).append(task)
|
|
task.add_done_callback(lambda t, k=msg.session_key: self._active_tasks.get(k, []) and self._active_tasks[k].remove(t) if t in self._active_tasks.get(k, []) else None)
|
|
|
|
async def _handle_stop(self, msg: InboundMessage) -> None:
|
|
"""Cancel all active tasks and subagents for the session."""
|
|
tasks = self._active_tasks.pop(msg.session_key, [])
|
|
cancelled = sum(1 for t in tasks if not t.done() and t.cancel())
|
|
for t in tasks:
|
|
try:
|
|
await t
|
|
except (asyncio.CancelledError, Exception):
|
|
pass
|
|
sub_cancelled = await self.subagents.cancel_by_session(msg.session_key)
|
|
total = cancelled + sub_cancelled
|
|
content = f"⏹ Stopped {total} task(s)." if total else "No active task to stop."
|
|
await self.bus.publish_outbound(OutboundMessage(
|
|
channel=msg.channel, chat_id=msg.chat_id, content=content,
|
|
))
|
|
|
|
async def _dispatch(self, msg: InboundMessage) -> None:
|
|
"""Process a message under the global lock."""
|
|
async with self._processing_lock:
|
|
try:
|
|
response = await self._process_message(msg)
|
|
if response is not None:
|
|
await self.bus.publish_outbound(response)
|
|
elif msg.channel == "cli":
|
|
await self.bus.publish_outbound(OutboundMessage(
|
|
channel=msg.channel, chat_id=msg.chat_id,
|
|
content="", metadata=msg.metadata or {},
|
|
))
|
|
except asyncio.CancelledError:
|
|
logger.info("Task cancelled for session {}", msg.session_key)
|
|
raise
|
|
except Exception:
|
|
logger.exception("Error processing message for session {}", msg.session_key)
|
|
await self.bus.publish_outbound(OutboundMessage(
|
|
channel=msg.channel, chat_id=msg.chat_id,
|
|
content="Sorry, I encountered an error.",
|
|
))
|
|
|
|
async def close_mcp(self) -> None:
|
|
"""Close MCP connections."""
|
|
if self._mcp_stack:
|
|
try:
|
|
await self._mcp_stack.aclose()
|
|
except (RuntimeError, BaseExceptionGroup):
|
|
pass # MCP SDK cancel scope cleanup is noisy but harmless
|
|
self._mcp_stack = None
|
|
|
|
def stop(self) -> None:
|
|
"""Stop the agent loop."""
|
|
self._running = False
|
|
logger.info("Agent loop stopping")
|
|
|
|
async def _process_message(
|
|
self,
|
|
msg: InboundMessage,
|
|
session_key: str | None = None,
|
|
on_progress: Callable[[str], Awaitable[None]] | None = None,
|
|
) -> OutboundMessage | None:
|
|
"""Process a single inbound message and return the response."""
|
|
# System messages: parse origin from chat_id ("channel:chat_id")
|
|
if msg.channel == "system":
|
|
channel, chat_id = (msg.chat_id.split(":", 1) if ":" in msg.chat_id
|
|
else ("cli", msg.chat_id))
|
|
logger.info("Processing system message from {}", msg.sender_id)
|
|
key = f"{channel}:{chat_id}"
|
|
session = self.sessions.get_or_create(key)
|
|
self._set_tool_context(channel, chat_id, msg.metadata.get("message_id"))
|
|
history = session.get_history(max_messages=self.memory_window)
|
|
messages = self.context.build_messages(
|
|
history=history,
|
|
current_message=msg.content, channel=channel, chat_id=chat_id,
|
|
)
|
|
final_content, _, all_msgs = await self._run_agent_loop(messages)
|
|
self._save_turn(session, all_msgs, 1 + len(history))
|
|
self.sessions.save(session)
|
|
return OutboundMessage(channel=channel, chat_id=chat_id,
|
|
content=final_content or "Background task completed.")
|
|
|
|
preview = msg.content[:80] + "..." if len(msg.content) > 80 else msg.content
|
|
logger.info("Processing message from {}:{}: {}", msg.channel, msg.sender_id, preview)
|
|
|
|
key = session_key or msg.session_key
|
|
session = self.sessions.get_or_create(key)
|
|
|
|
# Slash commands
|
|
cmd = msg.content.strip().lower()
|
|
if cmd == "/new":
|
|
lock = self._consolidation_locks.setdefault(session.key, asyncio.Lock())
|
|
self._consolidating.add(session.key)
|
|
try:
|
|
async with lock:
|
|
snapshot = session.messages[session.last_consolidated:]
|
|
if snapshot:
|
|
temp = Session(key=session.key)
|
|
temp.messages = list(snapshot)
|
|
if not await self._consolidate_memory(temp, archive_all=True):
|
|
return OutboundMessage(
|
|
channel=msg.channel, chat_id=msg.chat_id,
|
|
content="Memory archival failed, session not cleared. Please try again.",
|
|
)
|
|
except Exception:
|
|
logger.exception("/new archival failed for {}", session.key)
|
|
return OutboundMessage(
|
|
channel=msg.channel, chat_id=msg.chat_id,
|
|
content="Memory archival failed, session not cleared. Please try again.",
|
|
)
|
|
finally:
|
|
self._consolidating.discard(session.key)
|
|
if not lock.locked():
|
|
self._consolidation_locks.pop(session.key, None)
|
|
|
|
session.clear()
|
|
self.sessions.save(session)
|
|
self.sessions.invalidate(session.key)
|
|
return OutboundMessage(channel=msg.channel, chat_id=msg.chat_id,
|
|
content="New session started.")
|
|
if cmd == "/help":
|
|
return OutboundMessage(channel=msg.channel, chat_id=msg.chat_id,
|
|
content="🐈 nanobot commands:\n/new — Start a new conversation\n/stop — Stop the current task\n/help — Show available commands")
|
|
|
|
unconsolidated = len(session.messages) - session.last_consolidated
|
|
if (unconsolidated >= self.memory_window and session.key not in self._consolidating):
|
|
self._consolidating.add(session.key)
|
|
lock = self._consolidation_locks.setdefault(session.key, asyncio.Lock())
|
|
|
|
async def _consolidate_and_unlock():
|
|
try:
|
|
async with lock:
|
|
await self._consolidate_memory(session)
|
|
finally:
|
|
self._consolidating.discard(session.key)
|
|
if not lock.locked():
|
|
self._consolidation_locks.pop(session.key, None)
|
|
_task = asyncio.current_task()
|
|
if _task is not None:
|
|
self._consolidation_tasks.discard(_task)
|
|
|
|
_task = asyncio.create_task(_consolidate_and_unlock())
|
|
self._consolidation_tasks.add(_task)
|
|
|
|
self._set_tool_context(msg.channel, msg.chat_id, msg.metadata.get("message_id"))
|
|
if message_tool := self.tools.get("message"):
|
|
if isinstance(message_tool, MessageTool):
|
|
message_tool.start_turn()
|
|
|
|
history = session.get_history(max_messages=self.memory_window)
|
|
initial_messages = self.context.build_messages(
|
|
history=history,
|
|
current_message=msg.content,
|
|
media=msg.media if msg.media else None,
|
|
channel=msg.channel, chat_id=msg.chat_id,
|
|
)
|
|
|
|
async def _bus_progress(content: str, *, tool_hint: bool = False) -> None:
|
|
meta = dict(msg.metadata or {})
|
|
meta["_progress"] = True
|
|
meta["_tool_hint"] = tool_hint
|
|
await self.bus.publish_outbound(OutboundMessage(
|
|
channel=msg.channel, chat_id=msg.chat_id, content=content, metadata=meta,
|
|
))
|
|
|
|
final_content, _, all_msgs = await self._run_agent_loop(
|
|
initial_messages, on_progress=on_progress or _bus_progress,
|
|
)
|
|
|
|
if final_content is None:
|
|
final_content = "I've completed processing but have no response to give."
|
|
|
|
self._save_turn(session, all_msgs, 1 + len(history))
|
|
self.sessions.save(session)
|
|
|
|
if (mt := self.tools.get("message")) and isinstance(mt, MessageTool) and mt._sent_in_turn:
|
|
return None
|
|
|
|
preview = final_content[:120] + "..." if len(final_content) > 120 else final_content
|
|
logger.info("Response to {}:{}: {}", msg.channel, msg.sender_id, preview)
|
|
return OutboundMessage(
|
|
channel=msg.channel, chat_id=msg.chat_id, content=final_content,
|
|
metadata=msg.metadata or {},
|
|
)
|
|
|
|
def _save_turn(self, session: Session, messages: list[dict], skip: int) -> None:
|
|
"""Save new-turn messages into session, truncating large tool results."""
|
|
from datetime import datetime
|
|
for m in messages[skip:]:
|
|
entry = {k: v for k, v in m.items() if k != "reasoning_content"}
|
|
if entry.get("role") == "tool" and isinstance(entry.get("content"), str):
|
|
content = entry["content"]
|
|
if len(content) > self._TOOL_RESULT_MAX_CHARS:
|
|
entry["content"] = content[:self._TOOL_RESULT_MAX_CHARS] + "\n... (truncated)"
|
|
if entry.get("role") == "user" and isinstance(entry.get("content"), list):
|
|
entry["content"] = [
|
|
{"type": "text", "text": "[image]"} if (
|
|
c.get("type") == "image_url"
|
|
and c.get("image_url", {}).get("url", "").startswith("data:image/")
|
|
) else c
|
|
for c in entry["content"]
|
|
]
|
|
entry.setdefault("timestamp", datetime.now().isoformat())
|
|
session.messages.append(entry)
|
|
session.updated_at = datetime.now()
|
|
|
|
async def _consolidate_memory(self, session, archive_all: bool = False) -> bool:
|
|
"""Delegate to MemoryStore.consolidate(). Returns True on success."""
|
|
return await MemoryStore(self.workspace).consolidate(
|
|
session, self.provider, self.model,
|
|
archive_all=archive_all, memory_window=self.memory_window,
|
|
)
|
|
|
|
async def process_direct(
|
|
self,
|
|
content: str,
|
|
session_key: str = "cli:direct",
|
|
channel: str = "cli",
|
|
chat_id: str = "direct",
|
|
on_progress: Callable[[str], Awaitable[None]] | None = None,
|
|
) -> str:
|
|
"""Process a message directly (for CLI or cron usage)."""
|
|
await self._connect_mcp()
|
|
msg = InboundMessage(channel=channel, sender_id="user", chat_id=chat_id, content=content)
|
|
response = await self._process_message(msg, session_key=session_key, on_progress=on_progress)
|
|
return response.content if response else ""
|