lmstudio-community/Qwen3-Coder-30B-A3B-Instruct-MLX-4bit

curl http://localhost:1234/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "qwen3-coder-30b-a3b-instruct-mlx@4bit",
    "messages": [{"role": "user", "content": "What dell products do you have under $50 in electronics?"}],
    "tools": [
      {
        "type": "function",
        "function": {
          "name": "search_products",
          "description": "Search the product catalog by various criteria. Use this whenever a customer asks about product availability, pricing, or specifications.",
          "parameters": {
            "type": "object",
            "properties": {
              "query": {
                "type": "string",
                "description": "Search terms or product name"
              },
              "category": {
                "type": "string",
                "description": "Product category to filter by",
                "enum": ["electronics", "clothing", "home", "outdoor"]
              },
              "max_price": {
                "type": "number",
                "description": "Maximum price in dollars"
              }
            },
            "required": ["query"],
            "additionalProperties": false
          }
        }
      }
    ]
  }'

Response:

{
  "id": "chatcmpl-bba5dnu05g206j7fnsii2",
  "object": "chat.completion",
  "created": 1754360150,
  "model": "qwen3-coder-30b-a3b-instruct-mlx@6bit",
  "choices": [
    {
      "index": 0,
      "logprobs": null,
      "finish_reason": "tool_calls",
      "message": {
        "role": "assistant",
        "tool_calls": [
          {
            "id": "732918706",
            "type": "function",
            "function": {
              "name": "search_products",
              "arguments": "<parameter=query>dell</parameter><parameter=category>electronics</parameter><parameter=max_price>50</parameter>"
            }
          }
        ]
      }
    }
  ],
  "usage": {
    "prompt_tokens": 396,
    "completion_tokens": 42,
    "total_tokens": 438
  },
  "stats": {},
  "system_fingerprint": "qwen3-coder-30b-a3b-instruct-mlx@6bit"
}

The tool call result is not compatible with openai specs. The expected parameter syntax is

"arguments": "{"query":"dell","category":"electronics","max_price":50}"

but we are getting:
"arguments": "<parameter=query>dell<parameter=category>electronics<parameter=max_price>50"

How can we fix this issue?

lmstudio-community
/

Qwen3-Coder-30B-A3B-Instruct-MLX-4bit

OpenAI compatible API Tool Call