Factory's Droid Now Runs GPT-5.6 Sol Beating Claude by 13 Points

OpenAI's GPT-5.6 model family , Sol, Terra, and Luna , just landed inside Factory's Droid platform. For teams already using Droid as their autonomous engineering agent, this means access to OpenAI's newest generation of models on day one, routed automatically to the task at hand. No config changes, no model-switching, no tradeoffs.

The timing matters. GPT-5.6 hit general availability as a three-model family: Luna, Terra, and Sol, from smallest to largest. In OpenAI's new naming system, the number identifies a model's generation, while Sol, Terra, and Luna identify durable capability tiers that can advance on their own cadence. Factory is one of the first platforms to surface all three in a single, unified agent harness.

Three models, three jobs

The GPT-5.6 family is not just a single model with different price tags. Each tier has a distinct performance profile, and Factory has mapped each one to a specific engineering role inside Droid:

• Sol is the broad engineering generalist. It handles multi-step terminal work across code, data, security, and environment setup, and tends to inspect surrounding code before changing behavior. Sol is the flagship model, built for complex reasoning, coding, scientific work, cybersecurity, and long-running agentic tasks.
• Terra is the high-reasoning implementation model. It shines inside the edit-test-iterate loop, holds up well on long sessions, and supports cache reuse for efficiency. Terra has competitive performance to GPT-5.5 while being 2x cheaper.
• Luna is the standout for codebase research and document synthesis. It starts with the right moves: reading relevant files, fetching source material, and searching the repo with focused patterns. Luna is the smallest and most cost-efficient model in the series, aimed at faster, lower-cost workloads.