---
id: "willison-prompt-injection-design-patterns"
title: "Design Patterns for Securing LLM Agents against Prompt Injections"
creator: "Simon Willison"
url: "https://simonwillison.net/2025/Jun/13/prompt-injection-design-patterns/"
level: "advanced"
category: "agents"
models: ["any"]
source_date: "2025-06-13"
date_added: "2026-10-18"
---

[Agents and harnesses](/agents/index.md)

# Design Patterns for Securing LLM Agents against Prompt Injections

by Simon Willison

[Read the original →](https://simonwillison.net/2025/Jun/13/prompt-injection-design-patterns/)

Summary of a paper's defensive agent architectures.

Willison reviews published work on architectural defenses against prompt injection. The entry credits his commentary rather than presenting it as the underlying paper, and includes no operational attack examples.

Level: [Advanced](/levels/index.md#advanced)
Models: any
Category: [Agents and harnesses](/agents/index.md)
Tags: [security](/tags/security/index.md), [prompt-injection](/tags/prompt-injection/index.md)
Source date: 2025-06-13
Added: 2026-10-18
Last verified: 2026-10-18
Status: ok

Summary in our own words. All rights with the original creator. Correction or removal: DM on X.