gpt-5.6-terra — API, Pricing & Context Window | Vivgrid

gpt-5.6-terra is the balanced model in OpenAI's gpt-5.6 family and the successor to gpt-5.4, delivering most of gpt-5.6-sol's coding and reasoning quality at half the price. Its 1.05M-token context window makes it a strong default for production agents.

On Vivgrid, gpt-5.6-terra is served through a single OpenAI-compatible endpoint with geo-distributed acceleration across AMER and EMEA, reachable with the same unified key as the rest of the catalog.

Specifications

Pricing

Pricing in USD per 1M tokens, matching the provider's rates.

Quick start

Call gpt-5.6-terra through Vivgrid's unified, OpenAI-compatible endpoint. Get an API key from the Vivgrid Console.

curl https://api.vivgrid.com/v1/chat/completions \
  -H "Authorization: Bearer $VIVGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.6-terra",
    "messages": [
      { "role": "user", "content": "Say hello in English, Chinese and Spanish." }
    ],
    "stream": true
  }'

Requests beyond 272K input tokens are billed at the long-context rate: $5.00 input / $0.50 cached input / $22.50 output per 1M tokens.

Ideal use cases

• Production coding agents balancing quality, speed, and cost
• Whole-repository analysis within a 1.05M-token context
• High-volume tool-calling workflows on Chat Completions
• Teams standardizing on one model across coding and agent tasks

Related models

• gpt-5.6-sol — the flagship gpt-5.6 model
• gpt-5.6-luna — the fast, low-cost gpt-5.6 model
• gpt-5.4 — the prior-generation model at this tier