Text generation / OpenAI

gpt-5.6-terra

StreamFunction callingStructured outputs

Overview

GPT-5.6 Terra is a balanced model in OpenAI's GPT-5.6 series, positioned between the flagship Sol tier and the cost-efficient Luna tier. It is suited for everyday coding, reasoning, and agentic tasks where capability and cost need to be balanced, offering strong performance at roughly half the cost of Sol.

Model type: Text generation
Input: Text / Image
Output: Text
Endpoints: chat / chat_completion

Tiered billing details

Tier	Input	Output	Cache hit	Cache write
≤272K input tokens	$0.0020/1K	$0.0120/1K	$0.0002/1K	$0.0025/1K
>272K input tokens	$0.0040/1K	$0.0180/1K	$0.0004/1K	$0.0050/1K

Billed bylen (input context token count). Coefficient is the $ / 1M tokens price. Default group price (other groups converted by discount).

Code example

Call with gpt-5.6-terra :

curl https://www.starunion.net/v1/chat/completions \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.6-terra",
    "messages": [{ "role": "user", "content": "Hello" }]
  }'