gpt-5.5-pro (Text to Text (Chat))
POST
/
v1
/
chat
/
completions
gpt-5.5-pro (Text to Text (Chat))
curl --request POST \
--url https://gptproto.com/v1/chat/completionsimport requests
url = "https://gptproto.com/v1/chat/completions"
response = requests.post(url)
print(response.text)const options = {method: 'POST'};
fetch('https://gptproto.com/v1/chat/completions', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://gptproto.com/v1/chat/completions",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"net/http"
"io"
)
func main() {
url := "https://gptproto.com/v1/chat/completions"
req, _ := http.NewRequest("POST", url, nil)
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://gptproto.com/v1/chat/completions")
.asString();require 'uri'
require 'net/http'
url = URI("https://gptproto.com/v1/chat/completions")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
response = http.request(request)
puts response.read_bodyAuthentication
- Sign up for a GPTProto account at https://gptproto.com
- Navigate to the API Keys section in your dashboard
- Generate a new API key (sk-xxxxx)
- Copy and securely store your API key For authentication details, please refer to the Authentication section.
Initiate Request
curl --location 'https://gptproto.com/v1/chat/completions' \
--header 'Authorization: GPTPROTO_API_KEY' \
--header 'Content-Type: application/json' \
--data '{
"model": "gpt-5.5-pro",
"messages": [
{
"role": "user",
"content": "Who are you?"
}
],
"stream": false
}'
const axios = require('axios');
let data = JSON.stringify({
"model": "gpt-5.5-pro",
"messages": [
{
"role": "user",
"content": "Who are you?"
}
],
"stream": false
});
let config = {
method: 'post',
maxBodyLength: Infinity,
url: 'https://gptproto.com/v1/chat/completions',
headers: {
'Authorization': 'GPTPROTO_API_KEY',
'Content-Type': 'application/json'
},
data : data
};
axios.request(config)
.then((response) => {
console.log(JSON.stringify(response.data));
})
.catch((error) => {
console.log(error);
});
import requests
import json
url = "https://gptproto.com/v1/chat/completions"
payload = json.dumps({
"model": "gpt-5.5-pro",
"messages": [
{
"role": "user",
"content": "Who are you?"
}
],
"stream": False
})
headers = {
'Authorization': 'GPTPROTO_API_KEY',
'Content-Type': 'application/json'
}
response = requests.request("POST", url, headers=headers, data=payload)
print(response.text)
package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://gptproto.com/v1/chat/completions"
method := "POST"
payload := strings.NewReader(`{
"model": "gpt-5.5-pro",
"messages": [
{
"role": "user",
"content": "Who are you?"
}
],
"stream": false
}`)
client := &http.Client {
}
req, err := http.NewRequest(method, url, payload)
if err != nil {
fmt.Println(err)
return
}
req.Header.Add("Authorization", "GPTPROTO_API_KEY")
req.Header.Add("Content-Type", "application/json")
res, err := client.Do(req)
if err != nil {
fmt.Println(err)
return
}
defer res.Body.Close()
body, err := io.ReadAll(res.Body)
if err != nil {
fmt.Println(err)
return
}
fmt.Println(string(body))
}
Parameters
Core Parameters
| Parameter | Type | Required | Default | Range | Description |
|---|---|---|---|---|---|
model | string | ✅ Yes | - | - | Model ID used to generate the response, like gpt-4o or o3. OpenAI offers a wide range of models with different capabilities, performance characteristics, and price points. Refer to the model guide to browse and compare available models. |
messages | array | ✅ Yes | - | - | A list of messages comprising the conversation so far. Depending on the model you use, different message types (modalities) are supported, like text, images, and audio. |
>messages.role | string | ✅ Yes | - | developerusersystem | The role of the messages author. |
>messages.name | string | ❌ No | - | - | An optional name for the participant. Provides the model information to differentiate between participants of the same role. |
>messages.content | string / array | ✅ Yes | - | - | The contents of the developer message. |
>>messages.content.type | string | ✅ Yes | - | textimage_url | The type of the content part |
>>messages.content.text | string | ❌ No | - | - | The text content |
>>messages.content.image_url | object | ❌ No | - | - | The image URL content |
>>messages.content.image_url.url | string | ❌ No | - | - | The URL of the image |
Advanced Parameters
| Parameter | Type | Required | Default | Range | Description |
|---|---|---|---|---|---|
max_completion_tokens | integer / null | ❌ No | - | - | An upper bound for the number of tokens that can be generated for a completion, including visible output tokens and reasoning tokens. |
stream | boolean | ❌ No | false | truefalse | Whether to stream the response back incrementally. Defaults to false. |
Response Example
{
"id": "chatcmpl-abc123",
"object": "chat.completion",
"created": 1699896916,
"model": "gpt-5-chat",
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "The image shows a wooden boardwalk path extending through a lush green grassland."
},
"finish_reason": "stop"
}
],
"usage": {
"prompt_tokens": 1250,
"completion_tokens": 89,
"total_tokens": 1339
}
}
Error Codes
Common Error Codes
| Error Code | Error Name | Description |
|---|---|---|
| 401 | Unauthorized | API key is missing or invalid |
| 403 | Forbidden | Your API key doesn’t have permission to access this resource, or insufficient balance for the requested operation |
| 429 | Too Many Requests | You’ve exceeded your rate limit |
| 500 | Internal server error | An internal server error occurred |
| 503 | Content policy violation | Content blocked due to safety concerns (actual status code is 400) |
⌘I

