OpenAI has released GPT-5.6, and with it comes a new set of guidelines for how to prompt effectively[reference:147]. The model is available in three tiers, each designed for different use cases[reference:148]. For builders who want to push further, there is a lot to understand.
The three tiers
GPT-5.6 comes in three levels[reference:149]:
- Sol: Designed for the most difficult tasks, including complex reasoning, coding, and multi-step problem solving[reference:150]
- Terra: The mid-tier option for general-purpose tasks[reference:151]
- A third tier for lighter workloads
The Sol tier is where the real power lies. It is available in Cursor's agent mode and can be accessed by purchasing a Cursor Pro plan or higher[reference:152]. For developers building production-ready applications, Sol is the tier to focus on[reference:153].
Prompting guidelines
OpenAI's new guidelines for GPT-5.6 emphasize quality over quantity[reference:154]. The old approach of over-prompting, throwing as much context as possible at the model, is no longer the best strategy. The new guidelines focus on structure and clarity.
Each high-quality GPT-5.6 prompt has four components[reference:155]:
- Result: What the actual completion should look like
- Context: The background information the model needs
- Instructions: Clear, step-by-step directions
- Constraints: Any limitations or requirements
If you want to push further or do not want to memorize all the guidelines, you can build your own custom GPT and feed it the full guide as its knowledge base[reference:156]. Configure it to analyze any prompt you throw at it, understand the underlying logic, and rewrite it in GPT-5.6 style[reference:157].
Building with GPT-5.6
For developers, the GPT-5.6 Sol Projects Handbook offers a practical, project-based guide to creating production-ready AI applications, tool-using agents, multi-agent systems, and enterprise automation with the Responses API[reference:158]. The handbook covers building secure Sol applications with Python and TypeScript[reference:159].
In practice, using GPT-5.6 Sol in Cursor's agent mode is straightforward. Open the agent panel with Cmd+L (Mac) or Ctrl+L (Windows/Linux). Click the Model button at the bottom of the input area and select GPT-5.6 Sol from the list[reference:160].
Why this matters
GPT-5.6 represents a significant step forward in model capability. The new prompting guidelines reflect a shift in how OpenAI expects developers to interact with the model. Quality and structure matter more than volume. The three tiers give developers flexibility to choose the right tool for the job.
For builders, the opportunity is clear: learn the new guidelines, experiment with the Sol tier, and start building. The tools are there. The documentation is available. The rest is up to you.