Inside our approach to the Model Spec

2026-03-19 · Source: OpenAI News · Field: Technology & Digital — Artificial Intelligence & Machine Learning, AI Governance and Safety · Depth: Intermediate, long

Summary

OpenAI has introduced its Model Spec, a formal public framework defining how its AI models should behave, including instruction following, conflict resolution, user freedom, and safety across diverse queries. Launched in 2024 and continuously evolving, the Model Spec serves as an internal "north star" for training and evaluation, and an external reference for users, developers, researchers, and policymakers to understand and critique model behavior. It comprises high-level intent, public commitments, and a "Chain of Command" that prioritizes instructions based on authority levels, distinguishing between non-overridable "hard rules" for safety and legal compliance, and overridable "defaults" for steerability. The framework also includes interpretive aids like decision rubrics and concrete examples to ensure consistent application, aiming for transparency, accountability, and coordination in AI development.

Key takeaway

For AI Architects and Directors of AI/ML evaluating or deploying OpenAI models, understanding the Model Spec is crucial. It clarifies the hierarchy of model instructions, from immutable safety rules to steerable defaults, enabling you to design applications that effectively leverage model capabilities while adhering to defined behavioral boundaries. Your team should review the Model Spec to anticipate model responses, inform custom instruction design, and contribute to its evolution through feedback, ensuring alignment with your project's ethical and functional requirements.

Key insights

OpenAI's Model Spec provides a public, evolving framework for AI model behavior, balancing safety with user freedom.

Principles

• AI behavior must be explicit, inspectable, and debatable.
• Prioritize higher-authority instructions to resolve conflicts.
• Iterative deployment allows for continuous learning and adaptation.

Method

The Model Spec uses a "Chain of Command" to prioritize instructions from OpenAI, developers, and users, categorizing them into non-overridable "hard rules" and overridable "defaults," supplemented by decision rubrics and concrete examples.

In practice

• Consult the Model Spec for expected model behavior.
• Provide explicit instructions to override model defaults.
• Utilize public feedback mechanisms to influence AI behavior.

Topics

• AI Model Specification
• AI Governance
• Model Behavior
• AI Alignment
• Instruction Following

Code references

• openai/model_spec

Best for: CTO, Director of AI/ML, AI Architect, AI Engineer, AI Researcher, Policy Maker

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Editorial summary, takeaway, and curation by AIssential. Original article published by OpenAI News.