OpenAI: GPT-5.6 Terra API

GPT-5.6 Terra is designed for workloads that balance intelligence and cost. It roughly corresponds to the mini model tier used in earlier GPT-5 families.

Frequently Asked Questions

What is the context window of GPT-5.6 Terra?

GPT-5.6 Terra supports a context window of up to 1,050,000 tokens.

Does GPT-5.6 Terra support function calling?

Yes. GPT-5.6 Terra supports tool / function calling.

Does GPT-5.6 Terra support reasoning?

Yes. GPT-5.6 Terra is a reasoning-capable model.

What is the knowledge cutoff of GPT-5.6 Terra?

The knowledge cutoff of GPT-5.6 Terra is 2026-02-15.