Summary
On July 9, 2026 GitHub added OpenAI's newly released GPT-5.6 models — Sol, Terra, and Luna — to GitHub Copilot, letting developers select the flagship, balanced, or low-cost tier for chat and agent work on launch day.
What changed
GitHub made GPT-5.6 Sol, Terra, and Luna selectable in GitHub Copilot on July 9, 2026, the same day OpenAI released the family. Developers can pick among the three tiers in Copilot's model picker to trade capability against speed and cost for coding and agent tasks.
Why it matters
Copilot's value increasingly depends on offering frontier models the day they ship, and same-day GPT-5.6 access keeps it competitive with editors like Cursor and Vercel's gateway that race to expose new models first. Giving developers a cost-tiered choice (Sol, Terra, Luna) inside the tool also lets teams tune model spend per task without leaving their editor.
Evidence excerpt
OpenAI's GPT-5.6 Sol, Terra, and Luna are now available in GitHub Copilot (July 9, 2026), giving developers the three new tiers for chat and agent work.