Function Call

The function call capability of an LLM, also known as the tool use capability, allows the model to call external tools, thereby extending the application scope of the model. Specifically, it allows a model to directly call external functions or APIs to obtain the capability of executing specific tasks, obtaining real-time data, or enhancing decision-making. This feature not only broadens the application scope of models to tackle more complex and specific problems, but also enhances the practicality and interactivity of models. It establishes an efficient connection between LLMs and external systems, offering users richer and more personalized services.

The following uses tool use to represent the function call feature.

Figure 1 Tool use process

Procedure

The upper-layer application sends system prompts and user inputs to an LLM, and provides the tool set available for model execution.
Based on system prompts and user inputs, the model determines whether to directly return an answer or select one or more functions from the tool set provided by the application. If a tool is selected, return the tool name and tool parameters to the upper-layer application.
The upper-layer application parses the response from the inference engine, extracts the information about the selected tool, and executes the function selected by the model to obtain the tool use result.
The upper-layer application uses the tool use result to construct a prompt for generating an answer, and sends the prompt to the model again to request to generate a final answer.
The model summarizes information based on the tool use result, generates an answer, and returns the answer.

Constraints

The Atlas 800I A2 inference server, Atlas 800I A3 SuperPoD server, and Atlas 300I Duo inference card support this feature.
Currently, the ChatGLM3-6B, Qwen3-32B, Qwen3-235B-A22B, Qwen3-30B-A3B, DeepSeek-R1-0528, Qwen2.5-Instruct, and DeepSeek-V3.1 series models support this feature.
To use the function call feature, parameters listed in Parameter description must be configured for the DeepSeek-V3.1 series models. For other models, these parameters do not need to be configured.
Currently, only the OpenAI chat API is supported.
The function call feature can be used with the quantization, long sequence, multi-server inference, prefill-decode disaggregation, MoE, Multi-LoRA, SplitFuse, parallel decoding, expert parallelism, MTP, prefix cache, reasoning analysis (excluding DeepSeek-V3.1, which does not support enabling both function call and reasoning analysis in a single request), tensor parallelism, and MLA features. However, the SplitFuse, parallel decoding, and MTP features cannot be used with the function call feature in streaming inference.
Currently, the function call feature does not support the postprocessing parameters include_stop_str_in_output, stop, best_of, n, use_beam_search, and logprobs. If the temperature is set to a large value (which will increase sampling randomness), the stability of function call triggering may be affected.
The function call feature supports non-streaming inference. Only the function call feature of the Qwen3-32B, Qwen3-235B-A22B, Qwen3-30B-A3B, and DeepSeek-R1-0528 models supports streaming inference.
When a request packet contains the function call feature, the current version supports a maximum JSON nesting depth of 10 levels.

Parameter Description

Table 1 lists the parameters that can be configured when the function call feature is used.

Table 1 Supplementary parameters for the function call feature: models parameter in ModelConfig

Parameter	Value Type	Value Range	Parameter Description
chat_template	string	Path of the .jinja file	Imports a custom dialog template to replace the default dialog template. Default value: `""` For DeepSeek models, the default `chat_template` in `tokenizer_config.json` cannot be called using tools. You can use this parameter to input the `chat_template` that can be called using tools. This parameter can be used to input a custom template for DeepSeek, Qwen (LLM), ChatGLM, and Llama models.
tool_call_options	-	-	-
tool_call_parser	string	Optional Registered Name in Table 2 Registered ToolsCallProcessor ""	Parsing mode of the tool when the function call feature is enabled. Default value: `""` If this parameter is not set or is set to an incorrect value, the default tool parsing mode corresponding to the current model is used. When DeepSeek-V3.1 uses the function call feature, this parameter must be set to `deepseek_v31`. For other models, use the default value. This parameter is used together with `chat_template`. The corresponding `ToolsCallProcessor` is selected based on the function call format specified in `chat_template`.

Table 2 Registered ToolsCallProcessor

Tool Call Parser	Optional Registered Name	Description
ToolsCallProcessorChatglmV2	chatglm2_6b, chatglm_v2_6b, chatglm_v2, and chatglm2	Return the content directly without performing tool call parsing.
ToolsCallProcessorChatglmV3	chatglm3_6b, chatglm_v3_6b, chatglm_v3, and chatglm3	Tool call parser for ChatGLM3-6B.
ToolsCallProcessorChatglmV4	chatglm4_9b, chatglm_v4_9b, glm_4, and glm_4_9b	Tool call parser for GLM4-9B.
ToolsCallProcessorDeepseekv3	deepseek_v2, deepseek_v3, deepseekv2, and deepseekv3	Tool call parser for DeepSeek-R1-0528 and DeepSeek-V3-0324.
ToolsCallProcessorDeepseekv31	deepseek_v31 and deepseekv31	Tool call parser for DeepSeek-V3.1.
ToolsCallProcessorLlama	llama, llama3, and llama3_1	Tool call parser for Llama3.
ToolsCallProcessorQwen1_5_or_2	qwen1_5, qwen_1_5, qwen2, qwen_2, qwen1_5_or_2, and qwen_1_5_or_2	Tool call parser for Qwen1.5 and Qwen2.
ToolsCallProcessorQwen2_5	qwen2_5 and qwen_2_5	Tool call parser for Qwen2.5.
ToolsCallProcessorQwen3	qwen3, qwen3_moe, and hermes	Hermes tool call parsing for the Qwen3 and Qwen3-MoE series.

Inference

The following uses DeepSeek-V3.1 as an example to describe how to use the function call feature.

Open the config.json file of the server.

Installation using the .whl package:

cd {MindIE_installation_directory}/mindie_llm/
vi conf/config.json

Installation using the .run package:

cd {MindIE_installation_directory}/latest/mindie-service
vi conf/config.json

Set serving parameters.

Add the tool_call_parser and chat_template fields to the config.json file of the server based on Parameter description. For details about the serving parameters, see Service Parameter Configuration (Serving). The following is an example of parameter configuration:
```
 "ModelDeployConfig" :
        {
            "maxSeqLen" : 2560,
            "maxInputTokenLen" : 2048,
            "truncation" : 0,
            "ModelConfig" : [
                {
                    "modelInstanceType" : "Standard",
                    "modelName" : "dsv31",
                    "modelWeightPath" : "/data/weight/DeepSeek-V3.1",
                    "worldSize" : 16,
                    "cpuMemSize" : 0,
                    "npuMemSize" : -1,
                    "backendType" : "atb",
                    "trustRemoteCode" : false,
                    "async_scheduler_wait_time": 120,
                    "kv_trans_timeout": 10,
                    "kv_link_timeout": 1080,
                    "models": {
                            "deepseekv2": {
                                    "tool_call_options": {
                                            "tool_call_parser": "deepseek_v31"
                                    },
                                    "chat_template": "/path/to/tool_chat_template_deepseekv31.jinja"
                            }
                    }
                }
            ]
        },
```
- DeepSeek-V3.1: tool_call_parser must be set to deepseek_v31. Otherwise, deepseek_v3 is used by default, which is incompatible with the DeepSeek-V3.1 model format and may cause incorrect parsing.
- Other models: Steps 1 and 2 are not required. The system automatically matches the tool call parsing mode for the corresponding model. If this parameter is configured, change the value of deepseekv2 to model_type of the corresponding model.
- chat_template: If this parameter is specified, it will override the default chat_template defined in the model's tokenizer_config.json file. For DeepSeek-V3.1, DeepSeek-R1-0528, and DeepSeek-V3-0324, the default chat_template in the model weights' tokenizer_config.json file does not support function call. Therefore, you need to set chat_template to specify a template that supports function call.
- The format of chat_template (such as spaces and line breaks) may affect the accuracy of dataset and function call scoring.
Start the service.
- Installation using the .whl package:
```
mindie_llm_server
```
- Installation using the .run package:
```
./bin/mindieservice_daemon
```

Send a request to the service. For details about the parameters, see "Compatible with OpenAI APIs" > "Inference APIs".

Request example:

curl -H "Accept: application/json" -H "Content-type: application/json" --cacert ca.pem --cert client.pem  --key client.key.pem -X POST -d '{
    "model": "dsv31",
    "messages": [
        {
            "role": "system",
            "content": "You are a helpful customer support assistant. Use the supplied tools to assist the user."
        },
        {
            "role": "user",
            "content": "Hi, can you tell me the delivery date for my order?  my order number is 999888"
        }
    ],
    "tools": [
        {
            "type": "function",
            "function": {
                "name": "get_delivery_date",
                "description": "Get the delivery date for a customer\u0027s order. Call this whenever you need to know the delivery date, for example when a customer asks \u0027Where is my package\u0027",
                "parameters": {
                    "type": "object",
                    "properties": {
                        "order_id": {
                            "type": "string",
                            "description": "The customer\u0027s order ID."
                        }
                    },
                    "required": [
                        "order_id"
                    ],
                    "additionalProperties": false
                }
            }
        }
    ],
    "tool_choice": "auto",
    "stream": false
}'  https://127.0.0.1:1025/v1/chat/completions

Response example:

{
    "id": "chatcmpl-123",
    "object": "chat.completion",
    "created": 1677652288,
    "model": "dsv31",
    "choices": [
        {
            "index": 0,
            "message": {
                "role": "assistant",
                "content": "",
                "tool_calls": [
                    {
                        "function": {
                            "arguments": "{\"order_id\": \"999888\"}",
                            "name": "get_delivery_date"
                        },
                        "id": "call_JwmTNF3O",
                        "type": "function"
                    }
                ]
            },
            "finish_reason": "tool_calls"
        }
    ],
    "usage": {
        "prompt_tokens": 226,
        "completion_tokens": 122,
        "total_tokens": 348
    },
    "prefill_time": 200,
    "decode_time_arr": [56, 28, 28, 28, 28, ..., 28, 32, 28, 28, 41, 28, 25, 28]
}

Call the related local tool based on tool_calls returned by the model, use the assistant role to associate tool_calls with the ID returned by the API in 4, use the tool role to associate the tool execution result with the ID returned by the API in 4, and send a request to the LLM.

curl -H "Accept: application/json" -H "Content-type: application/json" --cacert ca.pem --cert client.pem  --key client.key.pem -X POST -d '{
    "model": "dsv31",
    "messages": [
        {
            "role": "user",
            "content": "Hi, can you tell me the delivery date for my order?  my order number is 999888"
        },
        {
            "role": "assistant",
            "content": "",
            "tool_calls": [
                {
                    "function": {
                        "arguments": "{\"order_id\": \"999888\"}",
                        "name": "get_delivery_date"
                    },
                    "id": "call_JwmTNF3O",
                    "type": "function"
                }
            ]
        },
        {
            "role": "tool",
            "content": "the delivery date is 2024.09.10.",
            "tool_call_id": "call_JwmTNF3O"
        }
    ],
    "stream": false,
    "max_tokens": 4096
}' https://127.0.0.1:1025/v1/chat/completions