Tool calling và JSON output với các mô hình open-weight

import json
import os

from openai import OpenAI

client = OpenAI(
    base_url="https://llmwithcrypto.com/api/v1",
    api_key=os.environ["LLMWITHCRYPTO_API_KEY"],
)

tools = [
    {
        "type": "function",
        "function": {
            "name": "get_order_status",
            "description": "Return the delivery status of an order.",
            "parameters": {
                "type": "object",
                "properties": {"order_id": {"type": "string"}},
                "required": ["order_id"],
            },
        },
    }
]


def get_order_status(order_id):
    return {"order_id": order_id, "status": "shipped", "eta": "2026-10-25"}


messages = [{"role": "user", "content": "Where is my order A-1042?"}]
while True:
    resp = client.chat.completions.create(model="gpt-oss-120b", messages=messages, tools=tools, max_tokens=300)
    msg = resp.choices[0].message
    if not msg.tool_calls:
        print(msg.content)
        break
    messages.append(msg)
    for call in msg.tool_calls:
        args = json.loads(call.function.arguments)
        result = get_order_status(**args)
        messages.append({"role": "tool", "tool_call_id": call.id, "content": json.dumps(result)})

{
  "id": "chatcmpl-3c9d27e1",
  "object": "chat.completion",
  "created": 1792742400,
  "model": "gpt-oss-120b",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": null,
        "tool_calls": [
          {
            "id": "call_7f31",
            "type": "function",
            "function": {
              "name": "get_order_status",
              "arguments": "{\"order_id\": \"A-1042\"}"
            }
          }
        ]
      },
      "finish_reason": "tool_calls"
    }
  ],
  "usage": {
    "prompt_tokens": 118,
    "completion_tokens": 22,
    "total_tokens": 140
  }
}

import OpenAI from 'openai';

const client = new OpenAI({
  baseURL: 'https://llmwithcrypto.com/api/v1',
  apiKey: process.env.LLMWITHCRYPTO_API_KEY,
});

const resp = await client.chat.completions.create({
  model: 'gpt-oss-120b',
  messages: [
    { role: 'system', content: 'Reply with a JSON object {"sentiment": "positive" | "negative" | "neutral", "reason": string}.' },
    { role: 'user', content: 'The delivery was late but support fixed it in an hour.' },
  ],
  response_format: { type: 'json_object' },
  temperature: 0.2,
  max_tokens: 150,
});
const result = JSON.parse(resp.choices[0].message.content);
console.log(result.sentiment, '-', result.reason);