fischer-agentkit/src/agentkit/core/react.py

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"""ReAct 推理-行动循环引擎
实现 ReAct (Reasoning-Action) 模式,使 Agent 能够自主推理、
选择工具并根据中间结果调整策略。
"""
import asyncio
import json
import logging
import re
import time
from dataclasses import dataclass, field
from datetime import datetime, timezone
from typing import TYPE_CHECKING, Any
from agentkit.core.exceptions import TaskCancelledError, TaskTimeoutError
from agentkit.core.protocol import CancellationToken
from agentkit.llm.gateway import LLMGateway
from agentkit.llm.protocol import LLMResponse
from agentkit.tools.base import Tool
from agentkit.telemetry.tracing import get_tracer, start_span, _OTEL_AVAILABLE
from agentkit.telemetry.metrics import (
agent_request_counter,
agent_duration_histogram,
)
if TYPE_CHECKING:
from agentkit.core.compressor import CompressionStrategy, ContextCompressor
from agentkit.core.trace import TraceRecorder
from agentkit.memory.retriever import MemoryRetriever
logger = logging.getLogger(__name__)
@dataclass
class ReActStep:
"""ReAct 单步记录"""
step: int
action: str # "tool_call" or "final_answer"
tool_name: str | None = None
arguments: dict[str, Any] | None = None
result: Any = None
content: str | None = None
tokens: int = 0
@dataclass
class ReActResult:
"""ReAct 执行结果"""
output: str
trajectory: list[ReActStep]
total_steps: int
total_tokens: int
status: str = "success" # "success" | "timeout" | "cancelled" | "partial"
fallback_strategy: str | None = None # e.g. "simplified_rewoo", "react", "direct"
@dataclass
class ReActEvent:
"""ReAct 执行事件"""
event_type: str # "thinking", "token", "tool_call", "tool_result", "confirmation_request", "final_answer", "error"
step: int
data: dict[str, Any] = field(default_factory=dict)
timestamp: str = field(default_factory=lambda: datetime.now(timezone.utc).isoformat())
class ReActEngine:
"""ReAct 推理-行动循环引擎
通过 Think (LLM 调用) → Act (工具执行) → Observe (结果观察) 的循环,
使 Agent 能够自主推理并选择工具完成任务。
"""
def __init__(self, llm_gateway: LLMGateway, max_steps: int = 10, default_timeout: float = 300.0, parallel_tools: bool | str = False):
if max_steps < 1:
raise ValueError(f"max_steps must be >= 1, got {max_steps}")
if isinstance(parallel_tools, str) and parallel_tools not in ("auto",):
raise ValueError(f"parallel_tools must be True, False, or 'auto', got {parallel_tools!r}")
self._llm_gateway = llm_gateway
self._max_steps = max_steps
self._default_timeout = default_timeout
self._parallel_tools = parallel_tools
def reset(self) -> None:
"""Reset internal state for reuse across conversations.
Call this before each execute/execute_stream to ensure clean state.
The engine itself (LLM gateway, config) is preserved.
"""
# ReActEngine is stateless between calls — conversation history,
# step counts, and trajectory are local to each execute call.
# This method exists for API clarity and future stateful extensions.
pass
async def execute(
self,
messages: list[dict[str, str]],
tools: list[Tool] | None = None,
model: str = "default",
agent_name: str = "",
task_type: str = "",
system_prompt: str | None = None,
trace_recorder: "TraceRecorder | None" = None,
memory_retriever: "MemoryRetriever | None" = None,
task_id: str | None = None,
compressor: "CompressionStrategy | None" = None,
retrieval_config: dict[str, Any] | None = None,
cancellation_token: CancellationToken | None = None,
timeout_seconds: float | None = None,
confirmation_handler: Any | None = None,
) -> ReActResult:
"""执行 ReAct 循环
1. 构建初始消息system_prompt + 任务消息)
2. 循环Think (LLM 调用) → Act (工具执行) → Observe (结果)
3. 停止条件LLM 不返回 tool_calls或达到 max_steps
4. 返回 ReActResult 包含输出和轨迹
Args:
cancellation_token: 协作式取消令牌,每次循环迭代检查是否已取消
timeout_seconds: 超时秒数0 表示无超时None 使用 default_timeout
"""
effective_timeout = timeout_seconds if timeout_seconds is not None else self._default_timeout
try:
if effective_timeout > 0:
result = await asyncio.wait_for(
self._execute_loop(
messages=messages,
tools=tools,
model=model,
agent_name=agent_name,
task_type=task_type,
system_prompt=system_prompt,
trace_recorder=trace_recorder,
memory_retriever=memory_retriever,
task_id=task_id,
compressor=compressor,
retrieval_config=retrieval_config,
cancellation_token=cancellation_token,
confirmation_handler=confirmation_handler,
),
timeout=effective_timeout,
)
else:
result = await self._execute_loop(
messages=messages,
tools=tools,
model=model,
agent_name=agent_name,
task_type=task_type,
system_prompt=system_prompt,
trace_recorder=trace_recorder,
memory_retriever=memory_retriever,
task_id=task_id,
compressor=compressor,
retrieval_config=retrieval_config,
cancellation_token=cancellation_token,
confirmation_handler=confirmation_handler,
)
except asyncio.TimeoutError:
raise TaskTimeoutError(
task_id=task_id or "",
timeout_seconds=int(effective_timeout),
)
except TaskCancelledError:
raise
return result
async def _execute_loop(
self,
messages: list[dict[str, str]],
tools: list[Tool] | None = None,
model: str = "default",
agent_name: str = "",
task_type: str = "",
system_prompt: str | None = None,
trace_recorder: "TraceRecorder | None" = None,
memory_retriever: "MemoryRetriever | None" = None,
task_id: str | None = None,
compressor: "CompressionStrategy | None" = None,
retrieval_config: dict[str, Any] | None = None,
cancellation_token: CancellationToken | None = None,
confirmation_handler: Any | None = None,
) -> ReActResult:
tools = tools or []
tool_schemas = self._build_tool_schemas(tools) if tools else None
if tool_schemas:
tool_names = [s["function"]["name"] for s in tool_schemas]
logger.info(f"ReActEngine executing with {len(tool_schemas)} tools: {tool_names}")
else:
logger.info("ReActEngine executing with NO tools")
# Telemetry: record agent request
agent_request_counter().add(1, {"agent.name": agent_name, "agent.type": task_type or "react"})
# Start telemetry span for the entire agent execution
_span_cm = None
_span = None
_exec_start = time.monotonic()
if _OTEL_AVAILABLE:
_span_cm = start_span(
"agent.execute",
attributes={"agent.name": agent_name, "agent.type": task_type or "react"},
)
_span = _span_cm.__enter__()
# Initialize before try so finally can access them
trajectory: list[ReActStep] = []
total_tokens = 0
trace_outcome = "error"
try:
# 启动轨迹记录
if trace_recorder is not None:
trace_recorder.start_trace(
task_id="",
agent_name=agent_name,
skill_name=task_type or None,
)
# Memory retrieval: 执行前检索相关上下文注入 system_prompt
if memory_retriever:
try:
query = str(messages[-1].get("content", "")) if messages else ""
top_k = (retrieval_config or {}).get("top_k", 5)
token_budget = (retrieval_config or {}).get("token_budget", 2000)
memory_context = await memory_retriever.get_context_string(
query=query,
top_k=top_k,
token_budget=token_budget,
)
if memory_context:
if system_prompt:
system_prompt += f"\n\n## 参考信息\n{memory_context}"
else:
system_prompt = f"## 参考信息\n{memory_context}"
except Exception as e:
logger.warning(f"Memory retrieval failed, continuing without context: {e}", exc_info=True)
# 构建初始消息
conversation: list[dict[str, Any]] = []
if system_prompt:
conversation.append({"role": "system", "content": system_prompt})
conversation.extend(messages)
# Context compression: 压缩超长对话历史
if compressor:
try:
conversation = await compressor.compress(conversation)
except Exception as e:
logger.warning(f"Context compression failed, continuing with original messages: {e}")
trace_outcome = "success"
step = 0
output = ""
while step < self._max_steps:
step += 1
# 协作式取消检查
if cancellation_token is not None:
cancellation_token.check()
# Think: 调用 LLM
llm_start = time.monotonic()
response = await self._llm_gateway.chat(
messages=conversation,
model=model,
agent_name=agent_name,
task_type=task_type,
tools=tool_schemas,
)
llm_duration_ms = int((time.monotonic() - llm_start) * 1000)
step_tokens = response.usage.total_tokens
total_tokens += step_tokens
# 检查是否有 Function Calling 的 tool_calls
if response.has_tool_calls:
# 记录 LLM 调用步骤
if trace_recorder is not None:
trace_recorder.record_step(
step=step,
action="llm_call",
duration_ms=llm_duration_ms,
tokens_used=step_tokens,
)
# Act: 执行工具调用
# 先记录 assistant 消息(含 tool_calls到对话历史
assistant_msg: dict[str, Any] = {
"role": "assistant",
"content": response.content or "",
"tool_calls": [
{
"id": tc.id,
"type": "function",
"function": {
"name": tc.name,
"arguments": json.dumps(tc.arguments),
},
}
for tc in response.tool_calls
],
}
conversation.append(assistant_msg)
# 执行工具调用
if self._parallel_tools == "auto" and len(response.tool_calls) > 1:
# Auto mode: mixed parallel/serial based on _parallelizable flag
parallelizable_set = set(self._get_parallelizable_indices(response.tool_calls))
serial_calls = [(i, tc) for i, tc in enumerate(response.tool_calls) if i not in parallelizable_set]
parallel_calls = [(i, tc) for i, tc in enumerate(response.tool_calls) if i in parallelizable_set]
# Result slots indexed by original position
all_results: list[Any] = [None] * len(response.tool_calls)
# Execute serial tools first (in order)
for i, tc in serial_calls:
tool_start = time.monotonic()
tool_result = await self._execute_tool(tc.name, tc.arguments, tools)
tool_duration_ms = int((time.monotonic() - tool_start) * 1000)
all_results[i] = (tc, tool_result, tool_duration_ms)
# Execute parallelizable tools in parallel
if len(parallel_calls) > 1:
para_results = await asyncio.gather(
*[self._execute_tool(tc.name, tc.arguments, tools) for _, tc in parallel_calls],
return_exceptions=True,
)
for j, (i, tc) in enumerate(parallel_calls):
tool_result = para_results[j]
if isinstance(tool_result, Exception):
tool_result = {"error": str(tool_result)}
all_results[i] = (tc, tool_result, 0)
elif len(parallel_calls) == 1:
i, tc = parallel_calls[0]
tool_result = await self._execute_tool(tc.name, tc.arguments, tools)
all_results[i] = (tc, tool_result, 0)
# Process all results in original order
for i, tc in enumerate(response.tool_calls):
tc_obj, tool_result, tool_duration_ms = all_results[i]
react_step = ReActStep(
step=step,
action="tool_call",
tool_name=tc.name,
arguments=tc.arguments,
result=tool_result,
tokens=step_tokens,
)
trajectory.append(react_step)
if trace_recorder is not None:
tool_error = None
if isinstance(tool_result, dict) and "error" in tool_result:
tool_error = tool_result["error"]
trace_recorder.record_step(
step=step,
action="tool_call",
tool_name=tc.name,
input_data=tc.arguments,
output_data=tool_result,
duration_ms=tool_duration_ms,
tokens_used=0,
error=tool_error,
)
tool_msg = await self._build_tool_result_message(tc.id, tool_result, compressor, tc.name)
conversation.append(tool_msg)
elif self._should_execute_parallel(response.tool_calls):
# 并行执行多个工具调用 (parallel_tools=True)
tool_results = await asyncio.gather(
*[self._execute_tool(tc.name, tc.arguments, tools) for tc in response.tool_calls],
return_exceptions=True,
)
for idx, tc in enumerate(response.tool_calls):
tool_result = tool_results[idx]
if isinstance(tool_result, Exception):
tool_result = {"error": str(tool_result)}
react_step = ReActStep(
step=step,
action="tool_call",
tool_name=tc.name,
arguments=tc.arguments,
result=tool_result,
tokens=step_tokens,
)
trajectory.append(react_step)
if trace_recorder is not None:
tool_error = None
if isinstance(tool_result, dict) and "error" in tool_result:
tool_error = tool_result["error"]
trace_recorder.record_step(
step=step,
action="tool_call",
tool_name=tc.name,
input_data=tc.arguments,
output_data=tool_result,
duration_ms=0,
tokens_used=0,
error=tool_error,
)
tool_msg = await self._build_tool_result_message(tc.id, tool_result, compressor, tc.name)
conversation.append(tool_msg)
else:
# 串行执行(单工具或 parallel_tools=False
for tc in response.tool_calls:
tool_start = time.monotonic()
tool_result = await self._execute_tool(tc.name, tc.arguments, tools)
# Handle confirmation flow
if isinstance(tool_result, dict) and tool_result.get("needs_confirmation"):
confirmation_id = tool_result["confirmation_id"]
command = tool_result.get("command", "")
reason = tool_result.get("reason", "")
approved = False
if confirmation_handler is not None:
try:
approved = await confirmation_handler(confirmation_id, command, reason)
except Exception as e:
logger.warning(f"Confirmation handler error: {e}")
if approved:
tool = self._find_tool(tc.name, tools)
if tool and hasattr(tool, '_is_dangerous'):
clean_args = {k: v for k, v in tc.arguments.items() if not k.startswith("_")}
clean_args["_skip_dangerous_check"] = True
try:
tool_result = await tool.safe_execute(**clean_args)
except Exception as e:
tool_result = {"error": f"Tool '{tc.name}' execution failed: {e}"}
else:
# Non-dangerous tool: confirmation was for the overall action,
# re-execute with skip flag to avoid re-triggering confirmation
clean_args = {k: v for k, v in tc.arguments.items() if not k.startswith("_")}
clean_args["_skip_dangerous_check"] = True
try:
tool_result = await tool.safe_execute(**clean_args) if tool else {"error": f"Tool '{tc.name}' not found"}
except Exception as e:
tool_result = {"error": f"Tool '{tc.name}' execution failed: {e}"}
else:
tool_result = {
"output": "",
"exit_code": 126,
"is_error": True,
"error_type": "permission_denied",
"message": f"用户拒绝执行命令: {command[:100]}",
}
tool_duration_ms = int((time.monotonic() - tool_start) * 1000)
react_step = ReActStep(
step=step,
action="tool_call",
tool_name=tc.name,
arguments=tc.arguments,
result=tool_result,
tokens=step_tokens,
)
trajectory.append(react_step)
# 记录工具调用步骤
if trace_recorder is not None:
tool_error = None
if isinstance(tool_result, dict) and "error" in tool_result:
tool_error = tool_result["error"]
trace_recorder.record_step(
step=step,
action="tool_call",
tool_name=tc.name,
input_data=tc.arguments,
output_data=tool_result,
duration_ms=tool_duration_ms,
tokens_used=0,
error=tool_error,
)
# Observe: 将工具结果添加到对话历史
tool_msg = await self._build_tool_result_message(tc.id, tool_result, compressor, tc.name)
conversation.append(tool_msg)
# Incremental compression: compress conversation if it's getting long
if self._should_compress(conversation, compressor):
try:
conversation = await compressor.compress(conversation)
except Exception as e:
logger.warning(f"Incremental compression failed: {e}")
else:
# 检查文本解析模式
parsed_calls = self._parse_text_tool_calls(response.content or "")
if parsed_calls and tools:
# 记录 LLM 调用步骤
if trace_recorder is not None:
trace_recorder.record_step(
step=step,
action="llm_call",
duration_ms=llm_duration_ms,
tokens_used=step_tokens,
)
# 文本解析模式执行工具
conversation.append({"role": "assistant", "content": response.content})
for pc in parsed_calls:
tool_start = time.monotonic()
tool_result = await self._execute_tool(pc["name"], pc["arguments"], tools)
tool_duration_ms = int((time.monotonic() - tool_start) * 1000)
react_step = ReActStep(
step=step,
action="tool_call",
tool_name=pc["name"],
arguments=pc["arguments"],
result=tool_result,
tokens=step_tokens,
)
trajectory.append(react_step)
# 记录工具调用步骤
if trace_recorder is not None:
tool_error = None
if isinstance(tool_result, dict) and "error" in tool_result:
tool_error = tool_result["error"]
trace_recorder.record_step(
step=step,
action="tool_call",
tool_name=pc["name"],
input_data=pc["arguments"],
output_data=tool_result,
duration_ms=tool_duration_ms,
tokens_used=0,
error=tool_error,
)
# 将工具结果添加到对话历史
tool_msg = await self._build_tool_result_message(pc.get("id", f"text_tc_{step}"), tool_result, compressor, pc["name"])
conversation.append(tool_msg)
# Incremental compression: compress conversation if it's getting long
if self._should_compress(conversation, compressor):
try:
conversation = await compressor.compress(conversation)
except Exception as e:
logger.warning(f"Incremental compression failed: {e}")
else:
# Final answer: LLM 没有调用工具,返回最终答案
react_step = ReActStep(
step=step,
action="final_answer",
content=response.content,
tokens=step_tokens,
)
trajectory.append(react_step)
output = response.content or ""
# 记录最终答案步骤
if trace_recorder is not None:
trace_recorder.record_step(
step=step,
action="final_answer",
output_data={"content": response.content},
duration_ms=llm_duration_ms,
tokens_used=step_tokens,
)
break
# 达到 max_steps 时,返回当前最佳输出
if step >= self._max_steps and not output:
trace_outcome = "partial"
# 使用最后一步的内容作为输出
if trajectory and trajectory[-1].content:
output = trajectory[-1].content
elif trajectory and trajectory[-1].result is not None:
output = str(trajectory[-1].result)
else:
output = response.content or ""
# 结束轨迹记录
if trace_recorder is not None:
trace_recorder.end_trace(outcome=trace_outcome)
# Memory storage: 执行后写入轨迹摘要到 EpisodicMemory
if memory_retriever and hasattr(memory_retriever, "store_episode"):
try:
summary = output[:500] if output else ""
await memory_retriever.store_episode(
key=f"task:{task_id or 'unknown'}",
value={"output_summary": summary, "agent_name": agent_name},
metadata={"task_type": task_type, "outcome": trace_outcome},
)
except Exception as e:
logger.warning(f"Failed to store task result in episodic memory: {e}")
return ReActResult(
output=output,
trajectory=trajectory,
total_steps=len(trajectory),
total_tokens=total_tokens,
)
finally:
# Telemetry: end span and record duration — always runs
_duration_ms = int((time.monotonic() - _exec_start) * 1000)
if _span is not None:
_span.set_attribute("agent.total_steps", len(trajectory))
_span.set_attribute("agent.total_tokens", total_tokens)
_span.set_attribute("agent.outcome", trace_outcome)
_span.set_attribute("agent.duration_ms", _duration_ms)
if _span_cm is not None:
_span_cm.__exit__(None, None, None)
agent_duration_histogram().record(_duration_ms, {"agent.name": agent_name})
async def execute_stream(
self,
messages: list[dict[str, str]],
tools: list[Tool] | None = None,
model: str = "default",
agent_name: str = "",
task_type: str = "",
system_prompt: str | None = None,
trace_recorder: "TraceRecorder | None" = None,
memory_retriever: "MemoryRetriever | None" = None,
task_id: str | None = None,
compressor: "CompressionStrategy | None" = None,
retrieval_config: dict[str, Any] | None = None,
cancellation_token: CancellationToken | None = None,
timeout_seconds: float | None = None,
confirmation_handler: Any | None = None,
):
"""Execute ReAct loop, yielding ReActEvent objects.
Same logic as execute() but yields events at each step instead of
accumulating a result.
"""
tools = tools or []
tool_schemas = self._build_tool_schemas(tools) if tools else None
if tool_schemas:
tool_names = [s["function"]["name"] for s in tool_schemas]
logger.info(f"ReActEngine executing with {len(tool_schemas)} tools: {tool_names}")
else:
logger.info("ReActEngine executing with NO tools")
# Telemetry: record agent request
agent_request_counter().add(1, {"agent.name": agent_name, "agent.type": task_type or "react"})
# Start telemetry span for the entire agent execution
_span_cm = None
_span = None
_exec_start = time.monotonic()
if _OTEL_AVAILABLE:
_span_cm = start_span(
"agent.execute_stream",
attributes={"agent.name": agent_name, "agent.type": task_type or "react"},
)
_span = _span_cm.__enter__()
# 启动轨迹记录
if trace_recorder is not None:
trace_recorder.start_trace(
task_id="",
agent_name=agent_name,
skill_name=task_type or None,
)
# Memory retrieval: 执行前检索相关上下文注入 system_prompt
if memory_retriever:
try:
query = str(messages[-1].get("content", "")) if messages else ""
top_k = (retrieval_config or {}).get("top_k", 5)
token_budget = (retrieval_config or {}).get("token_budget", 2000)
memory_context = await memory_retriever.get_context_string(
query=query,
top_k=top_k,
token_budget=token_budget,
)
if memory_context:
if system_prompt:
system_prompt += f"\n\n## 参考信息\n{memory_context}"
else:
system_prompt = f"## 参考信息\n{memory_context}"
except Exception as e:
logger.warning(f"Memory retrieval failed, continuing without context: {e}")
conversation: list[dict[str, Any]] = []
if system_prompt:
conversation.append({"role": "system", "content": system_prompt})
conversation.extend(messages)
# Context compression: 压缩超长对话历史
if compressor:
try:
conversation = await compressor.compress(conversation)
except Exception as e:
logger.warning(f"Context compression failed, continuing with original messages: {e}")
trajectory: list[ReActStep] = []
total_tokens = 0
step = 0
output = ""
trace_outcome = "success"
_stream_start = time.monotonic()
effective_timeout = timeout_seconds if timeout_seconds is not None else self._default_timeout
try:
while step < self._max_steps:
step += 1
# 协作式取消检查
if cancellation_token is not None:
cancellation_token.check()
# 超时检查
if effective_timeout > 0:
elapsed = time.monotonic() - _stream_start
if elapsed > effective_timeout:
trace_outcome = "timeout"
raise asyncio.TimeoutError(
f"execute_stream exceeded {effective_timeout}s timeout after {elapsed:.1f}s"
)
# Yield thinking event
yield ReActEvent(
event_type="thinking",
step=step,
data={"message": f"Step {step}: Calling LLM..."},
)
# Think: call LLM (with optional token streaming)
llm_start = time.monotonic()
# Use streaming for token-by-token output
stream_content_chunks: list[str] = []
stream_usage = None
stream_tool_calls: list[Any] = []
stream_model = model
async for chunk in self._llm_gateway.chat_stream(
messages=conversation,
model=model,
agent_name=agent_name,
task_type=task_type,
tools=tool_schemas,
):
if chunk.content:
stream_content_chunks.append(chunk.content)
yield ReActEvent(
event_type="token",
step=step,
data={"content": chunk.content},
)
if chunk.usage:
stream_usage = chunk.usage
if chunk.tool_calls:
stream_tool_calls = chunk.tool_calls
if chunk.model:
stream_model = chunk.model
# Build response-like object from stream
stream_content = "".join(stream_content_chunks)
response = self._build_response_from_stream(
content=stream_content,
tool_calls=stream_tool_calls,
usage=stream_usage,
model=stream_model,
)
llm_duration_ms = int((time.monotonic() - llm_start) * 1000)
step_tokens = response.usage.total_tokens
total_tokens += step_tokens
if response.has_tool_calls:
# 记录 LLM 调用步骤
if trace_recorder is not None:
trace_recorder.record_step(
step=step,
action="llm_call",
duration_ms=llm_duration_ms,
tokens_used=step_tokens,
)
# Record assistant message
assistant_msg: dict[str, Any] = {
"role": "assistant",
"content": response.content or "",
"tool_calls": [
{
"id": tc.id,
"type": "function",
"function": {
"name": tc.name,
"arguments": json.dumps(tc.arguments),
},
}
for tc in response.tool_calls
],
}
conversation.append(assistant_msg)
# Execute tool calls with parallel support
if self._parallel_tools and len(response.tool_calls) > 1 and self._should_execute_parallel(response.tool_calls):
# Parallel execution path
parallelizable_set = set(self._get_parallelizable_indices(response.tool_calls)) if self._parallel_tools == "auto" else set(range(len(response.tool_calls)))
serial_calls = [(i, tc) for i, tc in enumerate(response.tool_calls) if i not in parallelizable_set]
parallel_calls = [(i, tc) for i, tc in enumerate(response.tool_calls) if i in parallelizable_set]
all_results: list[Any] = [None] * len(response.tool_calls)
# Execute serial tools first (handles confirmation flow)
for i, tc in serial_calls:
yield ReActEvent(event_type="tool_call", step=step, data={"tool_name": tc.name, "arguments": tc.arguments})
tool_start = time.monotonic()
tool_result, confirm_events = await self._execute_tool_with_confirmation(tc, tools, step, confirmation_handler)
for ev in confirm_events:
yield ev
tool_duration_ms = int((time.monotonic() - tool_start) * 1000)
all_results[i] = (tc, tool_result, tool_duration_ms)
# Execute parallelizable tools concurrently
if len(parallel_calls) > 1:
para_results = await asyncio.gather(
*[self._execute_tool(tc.name, tc.arguments, tools) for _, tc in parallel_calls],
return_exceptions=True,
)
for j, (i, tc) in enumerate(parallel_calls):
tool_result = para_results[j]
if isinstance(tool_result, Exception):
tool_result = {"error": str(tool_result)}
all_results[i] = (tc, tool_result, 0)
elif len(parallel_calls) == 1:
i, tc = parallel_calls[0]
tool_result = await self._execute_tool(tc.name, tc.arguments, tools)
all_results[i] = (tc, tool_result, 0)
# Process all results in original order
for i, tc in enumerate(response.tool_calls):
tc_obj, tool_result, tool_duration_ms = all_results[i]
yield ReActEvent(event_type="tool_call", step=step, data={"tool_name": tc.name, "arguments": tc.arguments})
react_step = ReActStep(step=step, action="tool_call", tool_name=tc.name, arguments=tc.arguments, result=tool_result, tokens=step_tokens)
trajectory.append(react_step)
if trace_recorder is not None:
tool_error = None
if isinstance(tool_result, dict) and "error" in tool_result:
tool_error = tool_result["error"]
trace_recorder.record_step(step=step, action="tool_call", tool_name=tc.name, input_data=tc.arguments, output_data=tool_result, duration_ms=tool_duration_ms, tokens_used=0, error=tool_error)
yield ReActEvent(event_type="tool_result", step=step, data={"tool_name": tc.name, "result": tool_result})
tool_msg = await self._build_tool_result_message(tc.id, tool_result, compressor, tc.name)
conversation.append(tool_msg)
else:
# Serial execution path (with confirmation flow)
for tc in response.tool_calls:
# Yield tool_call event
yield ReActEvent(
event_type="tool_call",
step=step,
data={"tool_name": tc.name, "arguments": tc.arguments},
)
tool_start = time.monotonic()
tool_result = await self._execute_tool(tc.name, tc.arguments, tools)
tool_duration_ms = int((time.monotonic() - tool_start) * 1000)
# 检测工具返回的确认请求
if isinstance(tool_result, dict) and tool_result.get("needs_confirmation"):
confirmation_id = tool_result["confirmation_id"]
command = tool_result.get("command", "")
reason = tool_result.get("reason", "")
# Yield 确认请求事件
yield ReActEvent(
event_type="confirmation_request",
step=step,
data={
"confirmation_id": confirmation_id,
"tool_name": tc.name,
"command": command,
"reason": reason,
},
)
# 等待用户确认
approved = False
if confirmation_handler is not None:
try:
approved = await confirmation_handler(confirmation_id, command, reason)
except Exception as e:
logger.warning(f"Confirmation handler error: {e}")
if approved:
# 用户确认执行:使用 per-call override 绕过安全检查
tool = self._find_tool(tc.name, tools)
if tool and hasattr(tool, '_is_dangerous'):
# Strip internal metadata and pass skip_dangerous_check flag
clean_args = {k: v for k, v in tc.arguments.items() if not k.startswith("_")}
clean_args["_skip_dangerous_check"] = True
try:
tool_result = await tool.safe_execute(**clean_args)
finally:
pass # No shared state mutation needed
else:
# Non-dangerous tool: re-execute with skip flag
clean_args = {k: v for k, v in tc.arguments.items() if not k.startswith("_")}
clean_args["_skip_dangerous_check"] = True
try:
tool_result = await tool.safe_execute(**clean_args) if tool else {"error": f"Tool '{tc.name}' not found"}
except Exception as e:
tool_result = {"error": f"Tool '{tc.name}' execution failed: {e}"}
yield ReActEvent(
event_type="confirmation_result",
step=step,
data={"confirmation_id": confirmation_id, "approved": True},
)
else:
# 用户拒绝执行
tool_result = {
"output": "",
"exit_code": 126,
"is_error": True,
"error_type": "permission_denied",
"message": f"用户拒绝执行命令: {command[:100]}",
}
yield ReActEvent(
event_type="confirmation_result",
step=step,
data={"confirmation_id": confirmation_id, "approved": False},
)
tool_duration_ms = int((time.monotonic() - tool_start) * 1000)
react_step = ReActStep(
step=step,
action="tool_call",
tool_name=tc.name,
arguments=tc.arguments,
result=tool_result,
tokens=step_tokens,
)
trajectory.append(react_step)
if trace_recorder is not None:
tool_error = None
if isinstance(tool_result, dict) and "error" in tool_result:
tool_error = tool_result["error"]
trace_recorder.record_step(
step=step,
action="tool_call",
tool_name=tc.name,
input_data=tc.arguments,
output_data=tool_result,
duration_ms=tool_duration_ms,
tokens_used=0,
error=tool_error,
)
# Yield tool_result event
yield ReActEvent(
event_type="tool_result",
step=step,
data={"tool_name": tc.name, "result": tool_result},
)
tool_msg = await self._build_tool_result_message(tc.id, tool_result, compressor, tc.name)
conversation.append(tool_msg)
# Incremental compression: compress conversation if it's getting long
if self._should_compress(conversation, compressor):
try:
conversation = await compressor.compress(conversation)
except Exception as e:
logger.warning(f"Incremental compression failed: {e}")
else:
# Check text parsing mode
parsed_calls = self._parse_text_tool_calls(response.content or "")
if parsed_calls and tools:
# 记录 LLM 调用步骤
if trace_recorder is not None:
trace_recorder.record_step(
step=step,
action="llm_call",
duration_ms=llm_duration_ms,
tokens_used=step_tokens,
)
conversation.append({"role": "assistant", "content": response.content})
for pc in parsed_calls:
yield ReActEvent(
event_type="tool_call",
step=step,
data={"tool_name": pc["name"], "arguments": pc["arguments"]},
)
tool_start = time.monotonic()
tool_result = await self._execute_tool(pc["name"], pc["arguments"], tools)
tool_duration_ms = int((time.monotonic() - tool_start) * 1000)
trajectory.append(ReActStep(
step=step,
action="tool_call",
tool_name=pc["name"],
arguments=pc["arguments"],
result=tool_result,
tokens=step_tokens,
))
# 记录工具调用步骤
if trace_recorder is not None:
tool_error = None
if isinstance(tool_result, dict) and "error" in tool_result:
tool_error = tool_result["error"]
trace_recorder.record_step(
step=step,
action="tool_call",
tool_name=pc["name"],
input_data=pc["arguments"],
output_data=tool_result,
duration_ms=tool_duration_ms,
tokens_used=0,
error=tool_error,
)
yield ReActEvent(
event_type="tool_result",
step=step,
data={"tool_name": pc["name"], "result": tool_result},
)
tool_msg = await self._build_tool_result_message(
pc.get("id", f"text_tc_{step}"), tool_result, compressor, pc["name"]
)
conversation.append(tool_msg)
# Incremental compression: compress conversation if it's getting long
if self._should_compress(conversation, compressor):
try:
conversation = await compressor.compress(conversation)
except Exception as e:
logger.warning(f"Incremental compression failed: {e}")
else:
# Final answer
react_step = ReActStep(
step=step,
action="final_answer",
content=response.content,
tokens=step_tokens,
)
trajectory.append(react_step)
output = response.content or ""
# 记录最终答案步骤
if trace_recorder is not None:
trace_recorder.record_step(
step=step,
action="final_answer",
output_data={"content": response.content},
duration_ms=llm_duration_ms,
tokens_used=step_tokens,
)
yield ReActEvent(
event_type="final_answer",
step=step,
data={
"output": output,
"total_steps": len(trajectory),
"total_tokens": total_tokens,
},
)
break
if step >= self._max_steps and not output:
trace_outcome = "partial"
if trajectory and trajectory[-1].content:
output = trajectory[-1].content
elif trajectory and trajectory[-1].result is not None:
output = str(trajectory[-1].result)
else:
output = response.content or ""
yield ReActEvent(
event_type="final_answer",
step=step,
data={
"output": output,
"total_steps": len(trajectory),
"total_tokens": total_tokens,
"max_steps_reached": True,
},
)
finally:
# 结束轨迹记录 — always runs even if consumer doesn't fully iterate
if trace_recorder is not None:
trace_recorder.end_trace(outcome=trace_outcome)
# Telemetry: end span and record duration — always runs
_duration_ms = int((time.monotonic() - _exec_start) * 1000)
if _span is not None:
_span.set_attribute("agent.total_steps", len(trajectory))
_span.set_attribute("agent.total_tokens", total_tokens)
_span.set_attribute("agent.outcome", trace_outcome)
_span.set_attribute("agent.duration_ms", _duration_ms)
if _span_cm is not None:
_span_cm.__exit__(None, None, None)
agent_duration_histogram().record(_duration_ms, {"agent.name": agent_name})
# Memory storage: 执行后写入轨迹摘要到 EpisodicMemory
if memory_retriever and hasattr(memory_retriever, "store_episode"):
try:
summary = output[:500] if output else ""
await memory_retriever.store_episode(
key=f"task:{task_id or 'unknown'}",
value={"output_summary": summary, "agent_name": agent_name},
metadata={"task_type": task_type, "outcome": trace_outcome},
)
except Exception as e:
logger.warning(f"Failed to store task result in episodic memory: {e}")
def _build_tool_schemas(self, tools: list[Tool]) -> list[dict]:
"""将 Tool 对象转换为 OpenAI Function Calling schema 格式"""
schemas = []
for tool in tools:
schema = {
"type": "function",
"function": {
"name": tool.name,
"description": tool.description,
"parameters": tool.input_schema or {"type": "object", "properties": {}},
},
}
schemas.append(schema)
return schemas
@staticmethod
def _build_response_from_stream(
content: str,
tool_calls: list[Any],
usage: Any,
model: str,
) -> LLMResponse:
"""Build an LLMResponse from accumulated stream chunks."""
from agentkit.llm.protocol import LLMResponse, TokenUsage
if usage is None:
usage = TokenUsage()
return LLMResponse(
content=content,
tool_calls=tool_calls,
usage=usage,
model=model,
)
def _find_tool(self, name: str, tools: list[Tool]) -> Tool | None:
"""根据名称从可用工具中查找工具"""
for tool in tools:
if tool.name == name:
return tool
return None
# Default token threshold for incremental compression
_DEFAULT_COMPRESS_THRESHOLD = 8000
def _should_compress(self, conversation: list[dict], compressor: "CompressionStrategy | None") -> bool:
"""检查是否需要增量压缩"""
if not compressor:
return False
# Estimate tokens in conversation (rough: 4 chars ≈ 1 token)
total_chars = sum(len(str(m.get("content", ""))) for m in conversation)
estimated_tokens = total_chars // 4
return estimated_tokens > self._DEFAULT_COMPRESS_THRESHOLD
async def _build_tool_result_message(
self,
tool_call_id: str,
result: Any,
compressor: "CompressionStrategy | None" = None,
tool_name: str | None = None,
) -> dict:
"""构建工具结果消息用于对话历史"""
content = str(result)
if compressor and tool_name:
try:
content = await compressor.compress_tool_result(tool_name, result)
except Exception as e:
logger.warning(f"Tool result compression failed for '{tool_name}': {e}")
content = str(result)
return {
"role": "tool",
"tool_call_id": tool_call_id,
"content": content,
}
async def _execute_tool(
self, tool_name: str, arguments: dict[str, Any], tools: list[Tool]
) -> dict:
"""执行工具调用,处理成功和失败情况"""
tool = self._find_tool(tool_name, tools)
if tool is None:
error_msg = f"Tool '{tool_name}' not found"
logger.warning(error_msg)
return {"error": error_msg}
# Strip internal metadata keys before passing to tool
clean_args = {k: v for k, v in arguments.items() if not k.startswith("_")}
try:
result = await tool.safe_execute(**clean_args)
return result
except Exception as e:
error_msg = f"Tool '{tool_name}' execution failed: {e}"
logger.warning(error_msg)
return {"error": error_msg}
async def _execute_tool_with_confirmation(
self,
tc: Any,
tools: list[Tool],
step: int,
confirmation_handler: Any,
) -> tuple[Any, list[ReActEvent]]:
"""Execute a tool call with confirmation flow support.
Used in the parallel execution path for serial (non-parallelizable) tools
that may require user confirmation before execution.
Returns:
Tuple of (tool_result, list of ReActEvents to yield)
"""
events: list[ReActEvent] = []
tool_result = await self._execute_tool(tc.name, tc.arguments, tools)
# Check if tool returned a confirmation request
if isinstance(tool_result, dict) and tool_result.get("needs_confirmation"):
confirmation_id = tool_result["confirmation_id"]
command = tool_result.get("command", "")
reason = tool_result.get("reason", "")
events.append(ReActEvent(
event_type="confirmation_request",
step=step,
data={
"confirmation_id": confirmation_id,
"tool_name": tc.name,
"command": command,
"reason": reason,
},
))
# Wait for user confirmation
approved = False
if confirmation_handler is not None:
try:
approved = await confirmation_handler(confirmation_id, command, reason)
except Exception as e:
logger.warning(f"Confirmation handler error: {e}")
if approved:
# User approved: re-execute with _skip_dangerous_check
tool = self._find_tool(tc.name, tools)
if tool and hasattr(tool, '_is_dangerous'):
clean_args = {k: v for k, v in tc.arguments.items() if not k.startswith("_")}
clean_args["_skip_dangerous_check"] = True
try:
tool_result = await tool.safe_execute(**clean_args)
except Exception as e:
tool_result = {"error": f"Tool '{tc.name}' execution failed: {e}"}
else:
# Non-dangerous tool: re-execute with skip flag
clean_args = {k: v for k, v in tc.arguments.items() if not k.startswith("_")}
clean_args["_skip_dangerous_check"] = True
try:
tool_result = await tool.safe_execute(**clean_args) if tool else {"error": f"Tool '{tc.name}' not found"}
except Exception as e:
tool_result = {"error": f"Tool '{tc.name}' execution failed: {e}"}
events.append(ReActEvent(
event_type="confirmation_result",
step=step,
data={"confirmation_id": confirmation_id, "approved": True},
))
else:
# User rejected
tool_result = {
"output": "",
"exit_code": 126,
"is_error": True,
"error_type": "permission_denied",
"message": f"用户拒绝执行命令: {command[:100]}",
}
events.append(ReActEvent(
event_type="confirmation_result",
step=step,
data={"confirmation_id": confirmation_id, "approved": False},
))
return tool_result, events
def _should_execute_parallel(self, tool_calls: list[Any]) -> bool:
"""Determine if tool calls should be executed in parallel.
- parallel_tools=True: always parallel (if >1 tool)
- parallel_tools=False: never parallel
- parallel_tools="auto": parallel if any tool_call has _parallelizable=true in arguments
"""
if len(tool_calls) <= 1:
return False
if self._parallel_tools is True:
return True
if self._parallel_tools is False:
return False
# "auto" mode: check _parallelizable metadata in tool call arguments
if self._parallel_tools == "auto":
parallelizable_indices = self._get_parallelizable_indices(tool_calls)
return len(parallelizable_indices) > 1
return False
def _get_parallelizable_indices(self, tool_calls: list[Any]) -> list[int]:
"""Get indices of tool_calls that have _parallelizable=true in arguments.
LLM marks parallelizable tools by including _parallelizable: true
in the tool_call arguments.
"""
indices = []
for i, tc in enumerate(tool_calls):
args = tc.arguments if hasattr(tc, 'arguments') else {}
if isinstance(args, dict) and args.get("_parallelizable") is True:
indices.append(i)
return indices
def _parse_text_tool_calls(self, content: str) -> list[dict[str, Any]]:
"""从文本中解析工具调用模式
支持两种格式:
1. Action: tool_name(args)
2. ```tool\\n{"name": "...", "arguments": {...}}\\n```
"""
calls: list[dict[str, Any]] = []
# 格式 1: Action: tool_name(args)
action_pattern = re.compile(
r"Action:\s*(\w+)\((.+?)\)", re.DOTALL
)
for match in action_pattern.finditer(content):
name = match.group(1)
args_str = match.group(2)
try:
arguments = json.loads(args_str)
except (json.JSONDecodeError, TypeError):
arguments = {"raw_input": args_str}
calls.append({"name": name, "arguments": arguments})
if calls:
return calls
# 格式 2: ```tool\n{"name": "...", "arguments": {...}}\n```
code_block_pattern = re.compile(
r"```tool\s*\n(.*?)\n\s*```", re.DOTALL
)
for match in code_block_pattern.finditer(content):
json_str = match.group(1).strip()
try:
parsed = json.loads(json_str)
name = parsed.get("name", "")
arguments = parsed.get("arguments", {})
if name:
calls.append({"name": name, "arguments": arguments})
except (json.JSONDecodeError, TypeError):
logger.warning(f"Failed to parse tool call from text: {json_str}")
return calls