Files
LangBot/src/langbot/pkg/provider/runners/localagent.py

498 lines
20 KiB
Python

from __future__ import annotations
import json
import copy
import typing
from .. import runner
from ..modelmgr import requester as modelmgr_requester
import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
import langbot_plugin.api.entities.builtin.provider.message as provider_message
import langbot_plugin.api.entities.builtin.rag.context as rag_context
rag_combined_prompt_template = """
The following are relevant context entries retrieved from the knowledge base.
Please use them to answer the user's message.
Respond in the same language as the user's input.
<context>
{rag_context}
</context>
<user_message>
{user_message}
</user_message>
"""
SANDBOX_EXEC_TOOL_NAME = 'sandbox_exec'
SANDBOX_EXEC_SYSTEM_GUIDANCE = (
'When sandbox_exec is available, use it for exact calculations, statistics, structured data parsing, '
'and code execution instead of estimating mentally. If the user provides numbers, tables, CSV-like text, '
'JSON, or other data and asks for a computed answer, prefer running a short Python script in sandbox_exec '
'and then answer from the tool result. Unless the user explicitly asks for the script, code, or implementation '
'details, do not include the generated script in the final answer; return the result and a brief explanation only.'
)
SANDBOX_EXEC_WORKSPACE_GUIDANCE = (
'A default host workspace is mounted at /workspace for file tasks. When the user asks to read, create, or '
'modify local files in the working directory, use sandbox_exec with /workspace paths directly; do not ask the '
'user for sandbox parameters such as host_path unless they explicitly need a different directory.'
)
@runner.runner_class('local-agent')
class LocalAgentRunner(runner.RequestRunner):
"""Local agent request runner"""
def _build_sandbox_system_guidance(self) -> str:
guidance = SANDBOX_EXEC_SYSTEM_GUIDANCE
default_host_workspace = str(
getattr(getattr(self.ap, 'instance_config', None), 'data', {}).get('box', {}).get('default_host_workspace', '')
).strip()
if default_host_workspace:
guidance = f'{guidance} {SANDBOX_EXEC_WORKSPACE_GUIDANCE}'
return guidance
def _build_request_messages(
self,
query: pipeline_query.Query,
user_message: provider_message.Message,
) -> list[provider_message.Message]:
req_messages = query.prompt.messages.copy() + query.messages.copy()
if any(getattr(tool, 'name', None) == SANDBOX_EXEC_TOOL_NAME for tool in query.use_funcs or []):
req_messages.append(
provider_message.Message(
role='system',
content=self._build_sandbox_system_guidance(),
)
)
req_messages.append(user_message)
return req_messages
async def _get_model_candidates(
self,
query: pipeline_query.Query,
) -> list[modelmgr_requester.RuntimeLLMModel]:
"""Build ordered list of models to try: primary model + fallback models."""
candidates = []
# Primary model
if query.use_llm_model_uuid:
try:
primary = await self.ap.model_mgr.get_model_by_uuid(query.use_llm_model_uuid)
candidates.append(primary)
except ValueError:
self.ap.logger.warning(f'Primary model {query.use_llm_model_uuid} not found')
# Fallback models
fallback_uuids = (query.variables or {}).get('_fallback_model_uuids', [])
for fb_uuid in fallback_uuids:
try:
fb_model = await self.ap.model_mgr.get_model_by_uuid(fb_uuid)
candidates.append(fb_model)
except ValueError:
self.ap.logger.warning(f'Fallback model {fb_uuid} not found, skipping')
return candidates
async def _invoke_with_fallback(
self,
query: pipeline_query.Query,
candidates: list[modelmgr_requester.RuntimeLLMModel],
messages: list,
funcs: list,
remove_think: bool,
) -> tuple[provider_message.Message, modelmgr_requester.RuntimeLLMModel]:
"""Try non-streaming invocation with sequential fallback. Returns (message, model_used)."""
last_error = None
for model in candidates:
try:
msg = await model.provider.invoke_llm(
query,
model,
messages,
funcs if model.model_entity.abilities.__contains__('func_call') else [],
extra_args=model.model_entity.extra_args,
remove_think=remove_think,
)
return msg, model
except Exception as e:
last_error = e
self.ap.logger.warning(f'Model {model.model_entity.name} failed: {e}, trying next fallback...')
raise last_error or RuntimeError('No model candidates available')
async def _invoke_stream_with_fallback(
self,
query: pipeline_query.Query,
candidates: list[modelmgr_requester.RuntimeLLMModel],
messages: list,
funcs: list,
remove_think: bool,
) -> tuple[typing.AsyncGenerator, modelmgr_requester.RuntimeLLMModel]:
"""Try streaming invocation with sequential fallback. Returns (stream_generator, model_used).
Fallback is only possible before any chunks have been yielded to the client.
Once streaming starts, the model is committed.
"""
last_error = None
for model in candidates:
try:
stream = model.provider.invoke_llm_stream(
query,
model,
messages,
funcs if model.model_entity.abilities.__contains__('func_call') else [],
extra_args=model.model_entity.extra_args,
remove_think=remove_think,
)
# Attempt to get the first chunk to verify the stream works
first_chunk = await stream.__anext__()
async def _chain_stream(first, rest):
yield first
async for chunk in rest:
yield chunk
return _chain_stream(first_chunk, stream), model
except StopAsyncIteration:
# Empty stream — treat as success (model returned nothing)
async def _empty_stream():
return
yield # make it a generator
return _empty_stream(), model
except Exception as e:
last_error = e
self.ap.logger.warning(f'Model {model.model_entity.name} stream failed: {e}, trying next fallback...')
raise last_error or RuntimeError('No model candidates available')
async def run(
self, query: pipeline_query.Query
) -> typing.AsyncGenerator[provider_message.Message | provider_message.MessageChunk, None]:
"""Run request"""
pending_tool_calls = []
# Get knowledge bases list from query variables (set by PreProcessor,
# may have been modified by plugins during PromptPreProcessing)
kb_uuids = query.variables.get('_knowledge_base_uuids', [])
user_message = copy.deepcopy(query.user_message)
user_message_text = ''
if isinstance(user_message.content, str):
user_message_text = user_message.content
elif isinstance(user_message.content, list):
for ce in user_message.content:
if ce.type == 'text':
user_message_text += ce.text
break
if kb_uuids and user_message_text:
# only support text for now
all_results: list[rag_context.RetrievalResultEntry] = []
# Retrieve from each knowledge base
for kb_uuid in kb_uuids:
kb = await self.ap.rag_mgr.get_knowledge_base_by_uuid(kb_uuid)
if not kb:
self.ap.logger.warning(f'Knowledge base {kb_uuid} not found, skipping')
continue
result = await kb.retrieve(
user_message_text,
settings={
'bot_uuid': query.bot_uuid or '',
'sender_id': str(query.sender_id),
'session_name': f'{query.session.launcher_type.value}_{query.session.launcher_id}',
},
)
if result:
all_results.extend(result)
# Rerank step: re-score results using a rerank model if configured
local_agent_config = query.pipeline_config.get('ai', {}).get('local-agent', {})
rerank_model_uuid = local_agent_config.get('rerank-model', '')
if rerank_model_uuid == '__none__':
rerank_model_uuid = ''
self.ap.logger.info(
f'Rerank config: model_uuid={rerank_model_uuid!r}, '
f'results={len(all_results)}, '
f'local_agent_keys={list(local_agent_config.keys())}'
)
if all_results and rerank_model_uuid:
try:
rerank_model = await self.ap.model_mgr.get_rerank_model_by_uuid(rerank_model_uuid)
rerank_top_k = int(local_agent_config.get('rerank-top-k', 5))
doc_texts = []
for entry in all_results:
text = ' '.join(c.text for c in entry.content if c.type == 'text' and c.text)
doc_texts.append(text)
doc_texts_capped = doc_texts[:64]
scores = await rerank_model.provider.invoke_rerank(
model=rerank_model,
query=user_message_text,
documents=doc_texts_capped,
)
scored = sorted(scores, key=lambda x: x.get('relevance_score', 0), reverse=True)
top_indices = [s['index'] for s in scored[:rerank_top_k] if s['index'] < len(all_results)]
all_results = [all_results[i] for i in top_indices]
self.ap.logger.info(
f'Rerank complete: {len(doc_texts)} docs reranked -> top {len(all_results)} kept (top_k={rerank_top_k})'
)
except ValueError:
self.ap.logger.warning(f'Rerank model {rerank_model_uuid} not found, skipping rerank')
except Exception as e:
self.ap.logger.warning(f'Rerank failed, using original order: {e}')
final_user_message_text = ''
if all_results:
texts = []
idx = 1
for entry in all_results:
for content in entry.content:
if content.type == 'text' and content.text is not None:
texts.append(f'[{idx}] {content.text}')
idx += 1
rag_context_text = '\n\n'.join(texts)
final_user_message_text = rag_combined_prompt_template.format(
rag_context=rag_context_text, user_message=user_message_text
)
else:
final_user_message_text = user_message_text
self.ap.logger.debug(f'Final user message text: {final_user_message_text}')
for ce in user_message.content:
if ce.type == 'text':
ce.text = final_user_message_text
break
req_messages = self._build_request_messages(query, user_message)
try:
is_stream = await query.adapter.is_stream_output_supported()
except AttributeError:
is_stream = False
remove_think = query.pipeline_config['output'].get('misc', '').get('remove-think')
# Build ordered candidate list (primary + fallbacks)
candidates = await self._get_model_candidates(query)
if not candidates:
raise RuntimeError('No LLM model configured for local-agent runner')
self.ap.logger.debug(
f'localagent req: query={query.query_id} req_messages={req_messages} '
f'candidates={[m.model_entity.name for m in candidates]}'
)
if not is_stream:
# Non-streaming: invoke with fallback
msg, use_llm_model = await self._invoke_with_fallback(
query,
candidates,
req_messages,
query.use_funcs,
remove_think,
)
yield msg
final_msg = msg
else:
# Streaming: invoke with fallback
tool_calls_map: dict[str, provider_message.ToolCall] = {}
msg_idx = 0
accumulated_content = ''
last_role = 'assistant'
msg_sequence = 1
stream_src, use_llm_model = await self._invoke_stream_with_fallback(
query,
candidates,
req_messages,
query.use_funcs,
remove_think,
)
async for msg in stream_src:
msg_idx = msg_idx + 1
if msg.role:
last_role = msg.role
if msg.content:
accumulated_content += msg.content
if msg.tool_calls:
for tool_call in msg.tool_calls:
if tool_call.id not in tool_calls_map:
tool_calls_map[tool_call.id] = provider_message.ToolCall(
id=tool_call.id,
type=tool_call.type,
function=provider_message.FunctionCall(
name=tool_call.function.name if tool_call.function else '', arguments=''
),
)
if tool_call.function and tool_call.function.arguments:
tool_calls_map[tool_call.id].function.arguments += tool_call.function.arguments
if msg_idx % 8 == 0 or msg.is_final:
msg_sequence += 1
yield provider_message.MessageChunk(
role=last_role,
content=accumulated_content,
tool_calls=list(tool_calls_map.values()) if (tool_calls_map and msg.is_final) else None,
is_final=msg.is_final,
msg_sequence=msg_sequence,
)
final_msg = provider_message.MessageChunk(
role=last_role,
content=accumulated_content,
tool_calls=list(tool_calls_map.values()) if tool_calls_map else None,
msg_sequence=msg_sequence,
)
pending_tool_calls = final_msg.tool_calls
first_content = final_msg.content
if isinstance(final_msg, provider_message.MessageChunk):
first_end_sequence = final_msg.msg_sequence
req_messages.append(final_msg)
# Once a model succeeds, commit to it for the tool call loop
# (no fallback mid-conversation — different models may interpret tool results differently)
while pending_tool_calls:
for tool_call in pending_tool_calls:
try:
func = tool_call.function
if func.arguments:
parameters = json.loads(func.arguments)
else:
parameters = {}
func_ret = await self.ap.tool_mgr.execute_func_call(func.name, parameters, query=query)
# Handle return value content
tool_content = None
if (
isinstance(func_ret, list)
and len(func_ret) > 0
and isinstance(func_ret[0], provider_message.ContentElement)
):
tool_content = func_ret
else:
tool_content = json.dumps(func_ret, ensure_ascii=False)
if is_stream:
msg = provider_message.MessageChunk(
role='tool',
content=tool_content,
tool_call_id=tool_call.id,
)
else:
msg = provider_message.Message(
role='tool',
content=tool_content,
tool_call_id=tool_call.id,
)
yield msg
req_messages.append(msg)
except Exception as e:
err_msg = provider_message.Message(role='tool', content=f'err: {e}', tool_call_id=tool_call.id)
yield err_msg
req_messages.append(err_msg)
self.ap.logger.debug(
f'localagent req: query={query.query_id} req_messages={req_messages} '
f'use_llm_model={use_llm_model.model_entity.name}'
)
if is_stream:
tool_calls_map = {}
msg_idx = 0
accumulated_content = ''
last_role = 'assistant'
msg_sequence = first_end_sequence
tool_stream_src = use_llm_model.provider.invoke_llm_stream(
query,
use_llm_model,
req_messages,
query.use_funcs if use_llm_model.model_entity.abilities.__contains__('func_call') else [],
extra_args=use_llm_model.model_entity.extra_args,
remove_think=remove_think,
)
async for msg in tool_stream_src:
msg_idx += 1
if msg.role:
last_role = msg.role
# Prepend first-round content on first chunk of tool-call round
if msg_idx == 1:
accumulated_content = first_content if first_content is not None else accumulated_content
if msg.content:
accumulated_content += msg.content
if msg.tool_calls:
for tool_call in msg.tool_calls:
if tool_call.id not in tool_calls_map:
tool_calls_map[tool_call.id] = provider_message.ToolCall(
id=tool_call.id,
type=tool_call.type,
function=provider_message.FunctionCall(
name=tool_call.function.name if tool_call.function else '', arguments=''
),
)
if tool_call.function and tool_call.function.arguments:
tool_calls_map[tool_call.id].function.arguments += tool_call.function.arguments
if msg_idx % 8 == 0 or msg.is_final:
msg_sequence += 1
yield provider_message.MessageChunk(
role=last_role,
content=accumulated_content,
tool_calls=list(tool_calls_map.values()) if (tool_calls_map and msg.is_final) else None,
is_final=msg.is_final,
msg_sequence=msg_sequence,
)
final_msg = provider_message.MessageChunk(
role=last_role,
content=accumulated_content,
tool_calls=list(tool_calls_map.values()) if tool_calls_map else None,
msg_sequence=msg_sequence,
)
else:
# Non-streaming: use committed model directly (no fallback in tool loop)
msg = await use_llm_model.provider.invoke_llm(
query,
use_llm_model,
req_messages,
query.use_funcs if use_llm_model.model_entity.abilities.__contains__('func_call') else [],
extra_args=use_llm_model.model_entity.extra_args,
remove_think=remove_think,
)
yield msg
final_msg = msg
pending_tool_calls = final_msg.tool_calls
req_messages.append(final_msg)