128k OpenAI Context Window
Process massive documents with OpenAI GPT 5 mini. The 128,000 token window allows for deep RAG applications and long-form content analysis without losing track of details.

image
text
Image To Text (Response)
curl --request POST "https://gptproto.com/v1/responses" \
--header "Authorization: Bearer $GPTPROTO_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"model": "gpt-5-mini",
"input": [
{
"role": "user",
"content": [
{
"type": "input_text",
"text": "What is in this image?"
},
{
"type": "input_image",
"image_url": "https://tos.gptproto.com/resource/cat.png"
}
]
}
]
}'Image To Text (Chat)
curl --request POST "https://gptproto.com/v1/chat/completions" \
--header "Authorization: Bearer $GPTPROTO_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"model": "gpt-5-mini",
"messages": [
{
"role": "user",
"content": [
{
"type": "text",
"text": "What is in this image?"
},
{
"type": "image_url",
"image_url": {
"url": "https://tos.gptproto.com/resource/cat.png"
}
}
]
}
],
"max_tokens": 300
}'Discover the technical strengths that make OpenAI GPT 5 mini a leader in cost-efficient AI.
Process massive documents with OpenAI GPT 5 mini. The 128,000 token window allows for deep RAG applications and long-form content analysis without losing track of details.

Achieve 100% reliability in structured outputs. OpenAI GPT 5 mini uses constrained decoding to match your schemas perfectly, which is essential for automated data pipelines.

Reduce overhead with $0.15 per million tokens. OpenAI GPT 5 mini provides frontier-level intelligence at a fraction of the cost of larger models, maximizing your ROI.

Experience Time To First Token under 200ms. OpenAI GPT 5 mini is built for real-time chat and interactive apps where every millisecond counts for the user experience.

Follow these simple steps to set up your account, get credits, and start sending API requests to gpt 5 mini via GPT Proto.

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