fix(qwen): support reasoning-model params (max_completion_tokens, omit temperature) (#128)

The qwen_chat backend (the generic OpenAI-compatible client) hardcoded
max_tokens and always sent temperature, so reasoning models behind
OpenAI-compatible gateways (GPT-5.x, Claude Opus 4.8 via Azure/LiteLLM)
would 400.

- Add opt-in QWEN_CHAT_USE_MAX_COMPLETION_TOKENS (+ role variants) that
  swaps the payload key max_tokens -> max_completion_tokens.
- Treat an explicit empty / none / off temperature as "omit" instead of
  collapsing to the 0.7 default (via _resolve_temperature).
- Thread both through configure_qwen_chat / _update_config.
- Defaults unchanged; fully backward compatible. Adds 6 tests.

Fixes #127

Co-authored-by: Chirag Singhal <chirag127@users.noreply.github.com>
This commit is contained in:
Chirag Singhal
2026-07-12 21:54:40 +05:30
committed by GitHub
parent b309723baa
commit 46e8e800bc
3 changed files with 144 additions and 39 deletions
+9 -3
View File
@@ -13,13 +13,13 @@ from skillopt.model.backend_config import ( # noqa: F401
configure_codex_exec,
get_claude_code_exec_config,
get_codex_exec_config,
get_target_backend,
get_optimizer_backend,
get_target_backend,
is_optimizer_chat_backend,
is_target_chat_backend,
is_target_exec_backend,
is_optimizer_chat_backend,
set_target_backend,
set_optimizer_backend,
set_target_backend,
)
@@ -440,18 +440,21 @@ def configure_qwen_chat(
timeout_seconds: float | str | None = None,
max_tokens: int | str | None = None,
enable_thinking: bool | str | None = None,
use_max_completion_tokens: bool | str | None = None,
optimizer_base_url: str | None = None,
optimizer_api_key: str | None = None,
optimizer_temperature: float | str | None = None,
optimizer_timeout_seconds: float | str | None = None,
optimizer_max_tokens: int | str | None = None,
optimizer_enable_thinking: bool | str | None = None,
optimizer_use_max_completion_tokens: bool | str | None = None,
target_base_url: str | None = None,
target_api_key: str | None = None,
target_temperature: float | str | None = None,
target_timeout_seconds: float | str | None = None,
target_max_tokens: int | str | None = None,
target_enable_thinking: bool | str | None = None,
target_use_max_completion_tokens: bool | str | None = None,
) -> None:
_qwen.configure_qwen_chat(
base_url=base_url,
@@ -460,18 +463,21 @@ def configure_qwen_chat(
timeout_seconds=timeout_seconds,
max_tokens=max_tokens,
enable_thinking=enable_thinking,
use_max_completion_tokens=use_max_completion_tokens,
optimizer_base_url=optimizer_base_url,
optimizer_api_key=optimizer_api_key,
optimizer_temperature=optimizer_temperature,
optimizer_timeout_seconds=optimizer_timeout_seconds,
optimizer_max_tokens=optimizer_max_tokens,
optimizer_enable_thinking=optimizer_enable_thinking,
optimizer_use_max_completion_tokens=optimizer_use_max_completion_tokens,
target_base_url=target_base_url,
target_api_key=target_api_key,
target_temperature=target_temperature,
target_timeout_seconds=target_timeout_seconds,
target_max_tokens=target_max_tokens,
target_enable_thinking=target_enable_thinking,
target_use_max_completion_tokens=target_use_max_completion_tokens,
)
+60 -32
View File
@@ -1,13 +1,14 @@
"""OpenAI-compatible Qwen chat backend for optimizer and target paths."""
from __future__ import annotations
from dataclasses import dataclass
import json
import os
import threading
import time
import urllib.error
import urllib.request
from dataclasses import dataclass
from typing import Any
from skillopt.model.common import (
@@ -28,6 +29,7 @@ class QwenChatConfig:
temperature: float | None
enable_thinking: bool
deployment: str
use_max_completion_tokens: bool = False
def _parse_bool(value: Any, default: bool = False) -> bool:
@@ -56,6 +58,28 @@ def _role_env(role: str, key: str, default: str) -> str:
return os.environ.get(role_key) or os.environ.get(generic_key) or default
# Sentinels that mean "omit this optional parameter from the request payload".
# Reasoning models (e.g. GPT-5.x, Claude Opus 4.8) reject an explicit
# `temperature`, so allow it to be turned off via an empty string / none / off.
_OMIT_SENTINELS = {"", "none", "off", "null"}
def _resolve_temperature(role: str) -> float | None:
"""Return the temperature, or None to omit it entirely.
Unlike ``_role_env`` an *explicitly set* empty (or ``none``/``off``) value is
honored as "omit" instead of collapsing to the default. Precedence:
role-specific env -> generic env -> 0.7 default.
"""
for key in (f"{role.upper()}_QWEN_CHAT_TEMPERATURE", "QWEN_CHAT_TEMPERATURE"):
if key in os.environ:
raw = os.environ[key].strip()
if raw.lower() in _OMIT_SENTINELS:
return None
return float(raw)
return 0.7
def _initial_config(role: str) -> QwenChatConfig:
role_upper = role.upper()
deployment_env = "OPTIMIZER_DEPLOYMENT" if role == "optimizer" else "TARGET_DEPLOYMENT"
@@ -64,8 +88,9 @@ def _initial_config(role: str) -> QwenChatConfig:
api_key=_role_env(role, "API_KEY", ""),
timeout_seconds=float(_role_env(role, "TIMEOUT_SECONDS", "300") or 300),
max_tokens=_parse_int(_role_env(role, "MAX_TOKENS", "8000"), 8000),
temperature=_parse_optional_float(_role_env(role, "TEMPERATURE", "0.7")),
temperature=_resolve_temperature(role),
enable_thinking=_parse_bool(_role_env(role, "ENABLE_THINKING", "false")),
use_max_completion_tokens=_parse_bool(_role_env(role, "USE_MAX_COMPLETION_TOKENS", "false")),
deployment=(
os.environ.get(f"{role_upper}_QWEN_CHAT_MODEL")
or os.environ.get("QWEN_CHAT_MODEL")
@@ -186,10 +211,14 @@ def _chat_messages_impl(
timeout: float | None = None,
) -> tuple[Any, dict[str, int]]:
config = OPTIMIZER_CONFIG if role == "optimizer" else TARGET_CONFIG
token_limit = min(max_completion_tokens, config.max_tokens)
# Reasoning models on some gateways (GPT-5.x, o-series) require
# `max_completion_tokens` and reject the legacy `max_tokens`.
token_key = "max_completion_tokens" if config.use_max_completion_tokens else "max_tokens"
payload: dict[str, Any] = {
"model": deployment or config.deployment,
"messages": _json_safe(messages),
"max_tokens": min(max_completion_tokens, config.max_tokens),
token_key: token_limit,
}
if config.enable_thinking:
payload["chat_template_kwargs"] = {"enable_thinking": True}
@@ -219,7 +248,7 @@ def _chat_messages_impl(
return text, usage_info
except Exception as e: # noqa: BLE001
last_err = e
time.sleep(min(2 ** attempt, 30))
time.sleep(min(2**attempt, 30))
raise RuntimeError(f"Qwen chat call failed after {retries} retries: {last_err}")
@@ -231,18 +260,21 @@ def configure_qwen_chat(
timeout_seconds: float | str | None = None,
max_tokens: int | str | None = None,
enable_thinking: bool | str | None = None,
use_max_completion_tokens: bool | str | None = None,
optimizer_base_url: str | None = None,
optimizer_api_key: str | None = None,
optimizer_temperature: float | str | None = None,
optimizer_timeout_seconds: float | str | None = None,
optimizer_max_tokens: int | str | None = None,
optimizer_enable_thinking: bool | str | None = None,
optimizer_use_max_completion_tokens: bool | str | None = None,
target_base_url: str | None = None,
target_api_key: str | None = None,
target_temperature: float | str | None = None,
target_timeout_seconds: float | str | None = None,
target_max_tokens: int | str | None = None,
target_enable_thinking: bool | str | None = None,
target_use_max_completion_tokens: bool | str | None = None,
) -> None:
with _config_lock:
if base_url is not None:
@@ -256,29 +288,24 @@ def configure_qwen_chat(
if max_tokens is not None:
os.environ["QWEN_CHAT_MAX_TOKENS"] = str(max_tokens)
if enable_thinking is not None:
os.environ["QWEN_CHAT_ENABLE_THINKING"] = (
"true" if _parse_bool(enable_thinking) else "false"
os.environ["QWEN_CHAT_ENABLE_THINKING"] = "true" if _parse_bool(enable_thinking) else "false"
if use_max_completion_tokens is not None:
os.environ["QWEN_CHAT_USE_MAX_COMPLETION_TOKENS"] = (
"true" if _parse_bool(use_max_completion_tokens) else "false"
)
_update_config(
OPTIMIZER_CONFIG,
"optimizer",
base_url=optimizer_base_url if optimizer_base_url is not None else base_url,
api_key=optimizer_api_key if optimizer_api_key is not None else api_key,
temperature=(
optimizer_temperature
if optimizer_temperature is not None
else temperature
),
timeout_seconds=(
optimizer_timeout_seconds
if optimizer_timeout_seconds is not None
else timeout_seconds
),
temperature=(optimizer_temperature if optimizer_temperature is not None else temperature),
timeout_seconds=(optimizer_timeout_seconds if optimizer_timeout_seconds is not None else timeout_seconds),
max_tokens=optimizer_max_tokens if optimizer_max_tokens is not None else max_tokens,
enable_thinking=(
optimizer_enable_thinking
if optimizer_enable_thinking is not None
else enable_thinking
enable_thinking=(optimizer_enable_thinking if optimizer_enable_thinking is not None else enable_thinking),
use_max_completion_tokens=(
optimizer_use_max_completion_tokens
if optimizer_use_max_completion_tokens is not None
else use_max_completion_tokens
),
)
_update_config(
@@ -287,16 +314,13 @@ def configure_qwen_chat(
base_url=target_base_url if target_base_url is not None else base_url,
api_key=target_api_key if target_api_key is not None else api_key,
temperature=target_temperature if target_temperature is not None else temperature,
timeout_seconds=(
target_timeout_seconds
if target_timeout_seconds is not None
else timeout_seconds
),
timeout_seconds=(target_timeout_seconds if target_timeout_seconds is not None else timeout_seconds),
max_tokens=target_max_tokens if target_max_tokens is not None else max_tokens,
enable_thinking=(
target_enable_thinking
if target_enable_thinking is not None
else enable_thinking
enable_thinking=(target_enable_thinking if target_enable_thinking is not None else enable_thinking),
use_max_completion_tokens=(
target_use_max_completion_tokens
if target_use_max_completion_tokens is not None
else use_max_completion_tokens
),
)
@@ -311,6 +335,7 @@ def _update_config(
timeout_seconds: float | str | None = None,
max_tokens: int | str | None = None,
enable_thinking: bool | str | None = None,
use_max_completion_tokens: bool | str | None = None,
) -> None:
env_prefix = role.upper()
if base_url is not None:
@@ -321,7 +346,7 @@ def _update_config(
os.environ[f"{env_prefix}_QWEN_CHAT_API_KEY"] = config.api_key
if temperature is not None:
raw = str(temperature).strip()
config.temperature = float(raw) if raw else None
config.temperature = None if raw.lower() in _OMIT_SENTINELS else float(raw)
os.environ[f"{env_prefix}_QWEN_CHAT_TEMPERATURE"] = raw
if timeout_seconds is not None:
config.timeout_seconds = float(timeout_seconds)
@@ -331,8 +356,11 @@ def _update_config(
os.environ[f"{env_prefix}_QWEN_CHAT_MAX_TOKENS"] = str(max_tokens)
if enable_thinking is not None:
config.enable_thinking = _parse_bool(enable_thinking)
os.environ[f"{env_prefix}_QWEN_CHAT_ENABLE_THINKING"] = (
"true" if config.enable_thinking else "false"
os.environ[f"{env_prefix}_QWEN_CHAT_ENABLE_THINKING"] = "true" if config.enable_thinking else "false"
if use_max_completion_tokens is not None:
config.use_max_completion_tokens = _parse_bool(use_max_completion_tokens)
os.environ[f"{env_prefix}_QWEN_CHAT_USE_MAX_COMPLETION_TOKENS"] = (
"true" if config.use_max_completion_tokens else "false"
)