GPT-5 nano - Generate Image (AI Model · By )

API Documentation

API Reference

Images

Generate Image

Supported Model Code

Loading models...

GPT-5 nano (gpt-5-nano)

gpt-5-nano0 models support this endpoint

GPT-5 nano is the fastest and most cost-efficient version of GPT-5 from OpenAI, designed for speed-sensitive and cost-sensitive workloads such as summarization, classification, extraction, tagging, and high-volume lightweight automation. It supports text and image inputs with text output, a 400,000-token context window, and up to 128,000 output tokens. With reasoning token support, streaming, function calling, and structured outputs, GPT-5 nano is well suited for large-scale AI products that need low latency, low cost, reliable instruction following, and efficient processing of simple to moderately complex tasks.

Generate image

https://api.modelstream.ai

POST/v1/images/generations

Authentication

BearerAuth

AuthenticationBearer <token>

All API requests must be authenticated using a Bearer token in the Authorization header. Please ensure your API key is active.Authorization: Bearer sk-xxxxxx

Parameter Location: Header Param

Request Body

application/json

These parameters come from the selected model form_schema. Switching models updates this list and the request example.

system_prompt?string

Global instructions or persona for the model.

Example Value: You are a helpful and expert assistant.Placeholder: e.g., You are a senior software architect...

prompt*string

RequiredExample Value: Hello! What can you do?Placeholder: Enter your question or instructions...

image_urls?array

Supports multi-image understanding (optional).

Value Range: 0 ≤ value ≤ 10

image_detail?string

Example Value: auto

Enum/Options:

Auto: autoLow: lowHigh: high

reasoning_effort?string

Controls how much reasoning effort the model spends before answering.

Example Value: medium

Enum/Options:

Minimal: minimalLow: lowMedium: mediumHigh: high

verbosity?string

Controls how verbose the response is.

Example Value: medium

Enum/Options:

Low: lowMedium: mediumHigh: high

max_completion_tokens?number

Example Value: 8192Value Range: 1 ≤ value ≤ 128000

response_format?string

Example Value: text

Enum/Options:

Text: textJSON Object: json_object

stream?boolean

Example Value: true

Response Parameters

application/json

200apiDocs.responses.successGenerateImage

created?integer

Parameter description for Created

data?array

Parameter description for Data

curl -X POST "https://api.modelstream.ai/v1/images/generations" \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "gpt-5-nano",
  "messages": [
    {
      "role": "developer",
      "content": "You are a senior software architect."
    },
    {
      "role": "user",
      "content": [
        {
          "type": "text",
          "text": "Analyze this diagram and suggest improvements for scalability."
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "https://example.com/arch.png",
            "detail": "high"
          }
        }
      ]
    }
  ],
  "reasoning_effort": "high",
  "verbosity": "medium",
  "max_completion_tokens": 4096,
  "stream": true
}'

{
  "created": 0,
  "data": [
    {
      "url": "string",
      "b64_json": "string",
      "revised_prompt": "string"
    }
  ]
}

API Documentation

API Reference

Images

Generate Image

Supported Model Code

Loading models...

GPT-5 nano (gpt-5-nano)

gpt-5-nano0 models support this endpoint

Generate image

https://api.modelstream.ai

POST/v1/images/generations

Authentication

BearerAuth

AuthenticationBearer <token>

All API requests must be authenticated using a Bearer token in the Authorization header. Please ensure your API key is active.Authorization: Bearer sk-xxxxxx

Parameter Location: Header Param

Request Body

application/json

These parameters come from the selected model form_schema. Switching models updates this list and the request example.

system_prompt?string

Global instructions or persona for the model.

Example Value: You are a helpful and expert assistant.Placeholder: e.g., You are a senior software architect...

prompt*string

RequiredExample Value: Hello! What can you do?Placeholder: Enter your question or instructions...

image_urls?array

Supports multi-image understanding (optional).

Value Range: 0 ≤ value ≤ 10

image_detail?string

Example Value: auto

Enum/Options:

Auto: autoLow: lowHigh: high

reasoning_effort?string

Controls how much reasoning effort the model spends before answering.

Example Value: medium

Enum/Options:

Minimal: minimalLow: lowMedium: mediumHigh: high

verbosity?string

Controls how verbose the response is.

Example Value: medium

Enum/Options:

Low: lowMedium: mediumHigh: high

max_completion_tokens?number

Example Value: 8192Value Range: 1 ≤ value ≤ 128000

response_format?string

Example Value: text

Enum/Options:

Text: textJSON Object: json_object

stream?boolean

Example Value: true

Response Parameters

application/json

200apiDocs.responses.successGenerateImage

created?integer

Parameter description for Created

data?array

Parameter description for Data

curl -X POST "https://api.modelstream.ai/v1/images/generations" \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "gpt-5-nano",
  "messages": [
    {
      "role": "developer",
      "content": "You are a senior software architect."
    },
    {
      "role": "user",
      "content": [
        {
          "type": "text",
          "text": "Analyze this diagram and suggest improvements for scalability."
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "https://example.com/arch.png",
            "detail": "high"
          }
        }
      ]
    }
  ],
  "reasoning_effort": "high",
  "verbosity": "medium",
  "max_completion_tokens": 4096,
  "stream": true
}'

{
  "created": 0,
  "data": [
    {
      "url": "string",
      "b64_json": "string",
      "revised_prompt": "string"
    }
  ]
}

GPT-5 nano - Generate Image (AI Model · By ) | ModelStream