Chat API (Function Calls)

Short description: Chat API supporting model-generated function (tool) calls. Models can return suggested function calls during a conversation; the platform or caller may execute those functions.

---

Overview

• Method: POST
• Path: /v1/chat/completions
• Content-Type: application/json

Authentication

Supports common header-based authentication:

• OpenAI: Authorization: Bearer sk-xxx
• Anthropic: x-api-key: sk-xxx (may also require anthropic-version)
• Google: x-goog-api-key: sk-xxx

---

Request example

Body parameters

Parameter	Type	Required	Description
model	string	yes	Model name, e.g. gpt-4o
messages	array<object>	yes	Chat message list, typical item `{ role: 'user'
tools	array<object>	yes	List of tools (functions) the model may call; each item is type function，and includes name, description and parameters JSON Schema

Tool item (example structure):

{
  "type": "function",
  "function": {
    "name": "get_weather",
    "description": "Get current temperature for a given location.",
    "parameters": {
      "type": "object",
      "properties": {
        "location": { "type": "string", "description": "City and country e.g. Bogotá, Colombia" }
      },
      "required": ["location"],
      "additionalProperties": false
    },
    "strict": true
  }
}

After receiving the tools list, the model may return tool_calls in its response, indicating a suggested function call with arguments serialized as a JSON string.

---

curl example

curl -X POST "https://api.gpt.ge/v1/chat/completions" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer sk-xxxx" \
  -d '{
    "model": "gpt-4o",
    "messages": [{"role":"user","content":"What is the weather like in Paris today?"}],
    "tools": [
      {
        "type": "function",
        "function": {
          "name": "get_weather",
          "description": "Get current temperature for a given location.",
          "parameters": { "type": "object", "properties": { "location": { "type": "string" } }, "required": ["location"], "additionalProperties": false },
          "strict": true
        }
      }
    ]
  }'

JavaScript (fetch) example

fetch('https://api.gpt.ge/v1/chat/completions', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json', 'Authorization': 'Bearer sk-xxxx' },
  body: JSON.stringify({
    model: 'gpt-4o',
    messages: [{ role: 'user', content: 'What is the weather like in Paris today?' }],
    tools: [
      {
        type: 'function',
        function: {
          name: 'get_weather',
          description: 'Get current temperature for a given location.',
          parameters: { type: 'object', properties: { location: { type: 'string' } }, required: ['location'], additionalProperties: false },
          strict: true
        }
      }
    ]
  })
}).then(r => r.json()).then(console.log)

Python (requests) example

import requests

payload = {
  'model': 'gpt-4o',
  'messages': [{'role': 'user', 'content': 'What is the weather like in Paris today?'}],
  'tools': [
    {
      'type': 'function',
      'function': {
        'name': 'get_weather',
        'description': 'Get current temperature for a given location.',
        'parameters': { 'type': 'object', 'properties': { 'location': { 'type': 'string' } }, 'required': ['location'], 'additionalProperties': False },
        'strict': True
      }
    }
  ]
}

resp = requests.post('https://api.gpt.ge/v1/chat/completions', headers={'Content-Type':'application/json','Authorization':'Bearer sk-xxxx'}, json=payload)
print(resp.json())

---

Response example (200)

{
  "id": "chatcmpl-Ax2bU1RFE8P0Y9uqKcErQNLcx4dDe",
  "object": "chat.completion",
  "created": 1738634724,
  "model": "gpt-4o-2024-08-06",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": null,
        "tool_calls": [
          {
            "id": "call_FezxjoWuDV1CL3dITVFOjUzK",
            "type": "function",
            "function": {
              "name": "get_weather",
              "arguments": "{\"location\":\"Paris, France\"}"
            }
          }
        ],
        "refusal": null
      },
      "logprobs": null,
      "finish_reason": "tool_calls"
    }
  ],
  "usage": {
    "prompt_tokens": 65,
    "completion_tokens": 16,
    "total_tokens": 81,
    "prompt_tokens_details": { "cached_tokens": 0, "audio_tokens": 0 },
    "completion_tokens_details": { "reasoning_tokens": 0, "audio_tokens": 0, "accepted_prediction_tokens": 0, "rejected_prediction_tokens": 0 }
  },
  "system_fingerprint": "fp_f3927aa00d"
}