OpenAIFastHigh

GPT-5 Mini

Fast and efficient variant of GPT-5. Delivers strong performance across reasoning, coding, and creative tasks with a 1M token context window and 32K output tokens, at a fraction of the cost of GPT-5.

1 credits

per 1K tokens (avg)

1M token context window

32K max output tokens

Fast inference speed

Native vision (text + image)

Function calling & JSON mode

Structured outputs

Cost-effective GPT-5 performance

Run it right now

Test this model instantly in the Console Playground — no code required

Use with AI Assistant

Copy usage instructions for Claude, ChatGPT, or other AI

llms.txt

Model Specifications

Context Window

1.0M

tokens

Max Output

33K

tokens

Training Cutoff

2025-03

Compatible SDK

OpenAI

Capabilities

Vision

Function Calling

Streaming

JSON Mode

System Prompt

Token Pricing (per 1M tokens)

Token Type	Credits	USD Equivalent
Input Tokens	500	$0.50
Output Tokens	4,000	$4.00
Cached Tokens	125	$0.13

* 1 credit ≈ $0.001 (actual charges may vary based on usage)

Quick Start

curl -X POST "https://api.core.today/llm/openai/v1/chat/completions" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer cdt_your_api_key" \
  -d '{
  "model": "gpt-5-mini",
  "messages": [
    {
      "role": "system",
      "content": "You are a helpful assistant. Be concise and clear."
    },
    {
      "role": "user",
      "content": "Explain the difference between REST and GraphQL APIs, including when to use each."
    }
  ],
  "max_completion_tokens": 2000
}'

Parameters

Parameter	Type	Required	Default	Description
`messages`	array	Yes	-	Array of message objects with role and content
`model`	string	Yes	gpt-5-mini	Model identifier
`max_completion_tokens`	integer	No	4096	Maximum tokens in response (up to 32768). Note: use max_completion_tokens, not max_tokens
`reasoning_effort`	string	No	medium	Reasoning effort level: low, medium, or high
`stream`	boolean	No	false	Enable Server-Sent Events streaming
`response_format`	object	No	-	Format of response: { type: 'json_object' } for JSON mode
`tools`	array	No	-	List of tools (functions) the model can call

Examples

Quick Chat

Efficient general-purpose conversation with GPT-5 Mini

curl -X POST "https://api.core.today/llm/openai/v1/chat/completions" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer cdt_your_api_key" \
  -d '{
  "model": "gpt-5-mini",
  "messages": [
    {
      "role": "system",
      "content": "You are a helpful assistant. Be concise and clear."
    },
    {
      "role": "user",
      "content": "Explain the difference between REST and GraphQL APIs, including when to use each."
    }
  ],
  "max_completion_tokens": 2000
}'

Code Debugging

Debug code efficiently with GPT-5 Mini

curl -X POST "https://api.core.today/llm/openai/v1/chat/completions" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer cdt_your_api_key" \
  -d '{
  "model": "gpt-5-mini",
  "messages": [
    {
      "role": "system",
      "content": "You are an expert debugger. Find and fix bugs in the provided code."
    },
    {
      "role": "user",
      "content": "This Python function should return the nth Fibonacci number but it's running too slowly for large n. Optimize it:\n\ndef fib(n):\n    if n <= 1:\n        return n\n    return fib(n-1) + fib(n-2)"
    }
  ],
  "max_completion_tokens": 2000
}'