Research - Paper

The Instruction Hierarchy - Training Models to Prioritize Privileged Instructions

An OpenAI paper proposing that models should rank instructions by privilege and a data generation method that trains a model to ignore conflicting lower-privilege instructions; experiments apply it to GPT-3.5.

By Norbert HofmannPublished: 2026-09-26Last reviewed: 2026-09-26
Type
Paper
First published
2024-04-19
Authors
Eric Wallace et al.
Artifact
No
Table of contents

Overview

This paper addresses prompt injection from the model side. It argues that a core weakness is that models often treat developer instructions with the same priority as text from users or third parties, and proposes training models to respect an explicit hierarchy.

Bibliographic metadata
FieldValue
Resource typePaper
Original titleThe Instruction Hierarchy: Training LLMs to Prioritize Privileged Instructions
AuthorsEric Wallace, Kai Xiao, Reimar Leike, Lilian Weng, Johannes Heidecke, Alex Beutel
First public version2024-04-19
Publication statusOpenAI research publication, also available on arXiv (arXiv:2404.13208).
Focus areasModel training, Defenses, Direct injection, Indirect injection
ArtifactsNo code or data artifact listed
Last reviewed2026-09-26

Research question

Can a model be trained to follow higher-privilege instructions (for example from the system message) and selectively ignore conflicting lower-privilege instructions (for example in tool output), without losing general capability?

Method and artifact

The authors define how a model should behave when instructions of different privilege conflict, and propose a synthetic data generation method that demonstrates this behavior for training. They apply the method to GPT-3.5 and evaluate robustness against several attack types, including some not seen during training, as well as standard capability benchmarks. No public code or dataset artifact is listed here.

Key findings reported by the authors

Source statements: the points below summarize what the cited publication reports for the models and configurations it tested.

  • The authors identify equal treatment of instructions from different sources as a primary vulnerability underlying prompt injections and jailbreaks.
  • Training with the proposed data reportedly increases robustness drastically for the tested model, including against attack types not seen during training.
  • They report minimal degradation on standard capabilities.

Security interpretation

Site interpretation: this section is Prompt-Injection.net's explanation of why the work matters, not a claim made by the authors.

Instruction hierarchy is a model-facing robustness measure: it can make injection less likely to succeed, but the result is still a learned tendency, not an enforced rule. That is why this site pairs it with application-side controls such as authorization, least privilege and information flow restrictions, which hold even when the model is persuaded.

Limits and caveats

  • Published experiments apply the method to GPT-3.5; results do not automatically carry over to other models or later versions.
  • Robustness is measured on specific evaluations; adaptive attackers may find gaps.
  • The method does not give applications a verifiable guarantee about which instructions were followed.

How to use this work

Use it to understand why message roles matter and why putting untrusted content in the highest-privilege position is harmful. When designing systems, treat model-side hierarchy as one layer and keep authority decisions in application code.

  • Instructions and Instruction Hierarchies - How models prioritize competing instructions, why provider schemes differ, and why precedence is behavior rather than authorization or enforcement.
  • System Prompts - What system prompts can and cannot do, why hidden is not secret, how to compose dynamic prompts safely, and which controls belong outside the model.
  • Direct Prompt Injection - How attacker-controlled input competes with application instructions.
  • Indirect Prompt Injection - How external content can carry instructions into an AI system.
  • Agent Authorization - How to authorize AI agent actions outside the model: initiating principal, agent identity, resource, action, parameters, destination, scope and policy version, with exact-action binding and downstream revalidation.
  • Least Privilege - How to reduce the size, reach and lifetime of agent authority before any action is evaluated: identities, scopes, tool exposure, data access, JIT elevation, review and revocation readiness.

References

  1. The Instruction Hierarchy: Training LLMs to Prioritize Privileged Instructions (arXiv:2404.13208)arXiv · Research paper · 2024-04-19Reviewed 2026-09-26
  2. The Instruction HierarchyOpenAI · Research publicationReviewed 2026-09-26