refactor: extract runtime response guards into utils runtime module

This commit is contained in:
Xubin Ren
2026-04-02 13:54:40 +00:00
parent 714a4c7bb6
commit e4b335ce81
7 changed files with 449 additions and 44 deletions
+149 -38
View File
@@ -20,6 +20,13 @@ from nanobot.utils.helpers import (
maybe_persist_tool_result,
truncate_text,
)
from nanobot.utils.runtime import (
EMPTY_FINAL_RESPONSE_MESSAGE,
build_finalization_retry_message,
ensure_nonempty_tool_result,
is_blank_text,
repeated_external_lookup_error,
)
_DEFAULT_MAX_ITERATIONS_MESSAGE = (
"I reached the maximum number of tool call iterations ({max_iterations}) "
@@ -77,10 +84,11 @@ class AgentRunner:
messages = list(spec.initial_messages)
final_content: str | None = None
tools_used: list[str] = []
usage: dict[str, int] = {}
usage: dict[str, int] = {"prompt_tokens": 0, "completion_tokens": 0}
error: str | None = None
stop_reason = "completed"
tool_events: list[dict[str, str]] = []
external_lookup_counts: dict[str, int] = {}
for iteration in range(spec.max_iterations):
try:
@@ -96,41 +104,12 @@ class AgentRunner:
messages_for_model = messages
context = AgentHookContext(iteration=iteration, messages=messages)
await hook.before_iteration(context)
kwargs: dict[str, Any] = {
"messages": messages_for_model,
"tools": spec.tools.get_definitions(),
"model": spec.model,
"retry_mode": spec.provider_retry_mode,
"on_retry_wait": spec.progress_callback,
}
if spec.temperature is not None:
kwargs["temperature"] = spec.temperature
if spec.max_tokens is not None:
kwargs["max_tokens"] = spec.max_tokens
if spec.reasoning_effort is not None:
kwargs["reasoning_effort"] = spec.reasoning_effort
if hook.wants_streaming():
async def _stream(delta: str) -> None:
await hook.on_stream(context, delta)
response = await self.provider.chat_stream_with_retry(
**kwargs,
on_content_delta=_stream,
)
else:
response = await self.provider.chat_with_retry(**kwargs)
raw_usage = response.usage or {}
response = await self._request_model(spec, messages_for_model, hook, context)
raw_usage = self._usage_dict(response.usage)
context.response = response
context.usage = raw_usage
context.usage = dict(raw_usage)
context.tool_calls = list(response.tool_calls)
# Accumulate standard fields into result usage.
usage["prompt_tokens"] = usage.get("prompt_tokens", 0) + int(raw_usage.get("prompt_tokens", 0) or 0)
usage["completion_tokens"] = usage.get("completion_tokens", 0) + int(raw_usage.get("completion_tokens", 0) or 0)
cached = raw_usage.get("cached_tokens")
if cached:
usage["cached_tokens"] = usage.get("cached_tokens", 0) + int(cached)
self._accumulate_usage(usage, raw_usage)
if response.has_tool_calls:
if hook.wants_streaming():
@@ -158,13 +137,20 @@ class AgentRunner:
await hook.before_execute_tools(context)
results, new_events, fatal_error = await self._execute_tools(spec, response.tool_calls)
results, new_events, fatal_error = await self._execute_tools(
spec,
response.tool_calls,
external_lookup_counts,
)
tool_events.extend(new_events)
context.tool_results = list(results)
context.tool_events = list(new_events)
if fatal_error is not None:
error = f"Error: {type(fatal_error).__name__}: {fatal_error}"
final_content = error
stop_reason = "tool_error"
self._append_final_message(messages, final_content)
context.final_content = final_content
context.error = error
context.stop_reason = stop_reason
await hook.after_iteration(context)
@@ -178,6 +164,7 @@ class AgentRunner:
"content": self._normalize_tool_result(
spec,
tool_call.id,
tool_call.name,
result,
),
}
@@ -197,10 +184,27 @@ class AgentRunner:
await hook.after_iteration(context)
continue
clean = hook.finalize_content(context, response.content)
if response.finish_reason != "error" and is_blank_text(clean):
logger.warning(
"Empty final response on turn {} for {}; retrying with explicit finalization prompt",
iteration,
spec.session_key or "default",
)
if hook.wants_streaming():
await hook.on_stream_end(context, resuming=False)
response = await self._request_finalization_retry(spec, messages_for_model)
retry_usage = self._usage_dict(response.usage)
self._accumulate_usage(usage, retry_usage)
raw_usage = self._merge_usage(raw_usage, retry_usage)
context.response = response
context.usage = dict(raw_usage)
context.tool_calls = list(response.tool_calls)
clean = hook.finalize_content(context, response.content)
if hook.wants_streaming():
await hook.on_stream_end(context, resuming=False)
clean = hook.finalize_content(context, response.content)
if response.finish_reason == "error":
final_content = clean or spec.error_message or _DEFAULT_ERROR_MESSAGE
stop_reason = "error"
@@ -211,6 +215,16 @@ class AgentRunner:
context.stop_reason = stop_reason
await hook.after_iteration(context)
break
if is_blank_text(clean):
final_content = EMPTY_FINAL_RESPONSE_MESSAGE
stop_reason = "empty_final_response"
error = final_content
self._append_final_message(messages, final_content)
context.final_content = final_content
context.error = error
context.stop_reason = stop_reason
await hook.after_iteration(context)
break
messages.append(build_assistant_message(
clean,
@@ -249,22 +263,101 @@ class AgentRunner:
tool_events=tool_events,
)
def _build_request_kwargs(
self,
spec: AgentRunSpec,
messages: list[dict[str, Any]],
*,
tools: list[dict[str, Any]] | None,
) -> dict[str, Any]:
kwargs: dict[str, Any] = {
"messages": messages,
"tools": tools,
"model": spec.model,
"retry_mode": spec.provider_retry_mode,
"on_retry_wait": spec.progress_callback,
}
if spec.temperature is not None:
kwargs["temperature"] = spec.temperature
if spec.max_tokens is not None:
kwargs["max_tokens"] = spec.max_tokens
if spec.reasoning_effort is not None:
kwargs["reasoning_effort"] = spec.reasoning_effort
return kwargs
async def _request_model(
self,
spec: AgentRunSpec,
messages: list[dict[str, Any]],
hook: AgentHook,
context: AgentHookContext,
):
kwargs = self._build_request_kwargs(
spec,
messages,
tools=spec.tools.get_definitions(),
)
if hook.wants_streaming():
async def _stream(delta: str) -> None:
await hook.on_stream(context, delta)
return await self.provider.chat_stream_with_retry(
**kwargs,
on_content_delta=_stream,
)
return await self.provider.chat_with_retry(**kwargs)
async def _request_finalization_retry(
self,
spec: AgentRunSpec,
messages: list[dict[str, Any]],
):
retry_messages = list(messages)
retry_messages.append(build_finalization_retry_message())
kwargs = self._build_request_kwargs(spec, retry_messages, tools=None)
return await self.provider.chat_with_retry(**kwargs)
@staticmethod
def _usage_dict(usage: dict[str, Any] | None) -> dict[str, int]:
if not usage:
return {}
result: dict[str, int] = {}
for key, value in usage.items():
try:
result[key] = int(value or 0)
except (TypeError, ValueError):
continue
return result
@staticmethod
def _accumulate_usage(target: dict[str, int], addition: dict[str, int]) -> None:
for key, value in addition.items():
target[key] = target.get(key, 0) + value
@staticmethod
def _merge_usage(left: dict[str, int], right: dict[str, int]) -> dict[str, int]:
merged = dict(left)
for key, value in right.items():
merged[key] = merged.get(key, 0) + value
return merged
async def _execute_tools(
self,
spec: AgentRunSpec,
tool_calls: list[ToolCallRequest],
external_lookup_counts: dict[str, int],
) -> tuple[list[Any], list[dict[str, str]], BaseException | None]:
batches = self._partition_tool_batches(spec, tool_calls)
tool_results: list[tuple[Any, dict[str, str], BaseException | None]] = []
for batch in batches:
if spec.concurrent_tools and len(batch) > 1:
tool_results.extend(await asyncio.gather(*(
self._run_tool(spec, tool_call)
self._run_tool(spec, tool_call, external_lookup_counts)
for tool_call in batch
)))
else:
for tool_call in batch:
tool_results.append(await self._run_tool(spec, tool_call))
tool_results.append(await self._run_tool(spec, tool_call, external_lookup_counts))
results: list[Any] = []
events: list[dict[str, str]] = []
@@ -280,8 +373,23 @@ class AgentRunner:
self,
spec: AgentRunSpec,
tool_call: ToolCallRequest,
external_lookup_counts: dict[str, int],
) -> tuple[Any, dict[str, str], BaseException | None]:
_HINT = "\n\n[Analyze the error above and try a different approach.]"
lookup_error = repeated_external_lookup_error(
tool_call.name,
tool_call.arguments,
external_lookup_counts,
)
if lookup_error:
event = {
"name": tool_call.name,
"status": "error",
"detail": "repeated external lookup blocked",
}
if spec.fail_on_tool_error:
return lookup_error + _HINT, event, RuntimeError(lookup_error)
return lookup_error + _HINT, event, None
prepare_call = getattr(spec.tools, "prepare_call", None)
tool, params, prep_error = None, tool_call.arguments, None
if callable(prepare_call):
@@ -361,8 +469,10 @@ class AgentRunner:
self,
spec: AgentRunSpec,
tool_call_id: str,
tool_name: str,
result: Any,
) -> Any:
result = ensure_nonempty_tool_result(tool_name, result)
try:
content = maybe_persist_tool_result(
spec.workspace,
@@ -395,6 +505,7 @@ class AgentRunner:
normalized = self._normalize_tool_result(
spec,
str(message.get("tool_call_id") or f"tool_{idx}"),
str(message.get("name") or "tool"),
message.get("content"),
)
if normalized != message.get("content"):