openai.BadRequestError: Error code: 400 - {'error': {'message': 'deepseek-reasoner does not support this tool_choice', 'type': 'invalid_request_error', 'param': None, 'code': 'invalid_request_error'}}

[hjing100]

Description of the bug:

Actual vs expected behavior:

No response

Any other information you'd like to share?

No response

[hjing100]

import argparse
from langchain_core.messages import HumanMessage
from agent.graph import graph

def main() -> None:
"""Run the research agent from the command line."""
parser = argparse.ArgumentParser(description="Run the LangGraph research agent")
parser.add_argument("question",default="大模型是什么？", help="Research question")
parser.add_argument(
"--initial-queries",
type=int,
default=3,
help="Number of initial search queries",
)
parser.add_argument(
"--max-loops",
type=int,
default=2,
help="Maximum number of research loops",
)
parser.add_argument(
"--reasoning-model",
default="deepseek-r1-0528", # default="gemini-2.5-pro-preview-05-06",
help="Model for the final answer",
)
args = parser.parse_args()

state = {
    "messages": [HumanMessage(content=args.question)],
    "initial_search_query_count": args.initial_queries,
    "max_research_loops": args.max_loops,
    "reasoning_model": args.reasoning_model,
}
print("line35")
print(state)

result = graph.invoke(state)
messages = result.get("messages", [])
if messages:
    print(messages[-1].content)

if name == "main":
main()