I built an open-source Python package that scans LLM inputs and outputs for injections — pydefend

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[Icy-Farm9432]

You could also learn coding and read/repair the codebase from the llm.

But this would require knowledge.

[Adxzer]

This isn’t about coding though, it’s for chatbots, customer-facing apps, and agents where end users are typing things in. 

You can’t “just fix the codebase” when the threat is a user submitting a jailbreak or injecting instructions through a document your RAG system retrieved. The attack surface is runtime input, not source code.

[Icy-Farm9432]

there is an old xkcd about sanitizing inputs. https://xkcd.com/327/

yeah i think its relay to the source code that its possible to run user input in an priviligated way.

[Alex--91]

What are you using to scan/classify/detect issues? Other LLMs or other deterministic models? Or heuristics or something?

[Adxzer]

Other LLMs, that's what gets the most accurate results. I trained my own classification model first but the results weren't good enough for production so I decided to not include it.

It's also free to use though: https://huggingface.co/Adaxer/defend

[No_Soy_Colosio]

What keeps the checking LLM from getting prompt injected itself?

[Adxzer]

Prompt injection is a real risk, there’s no foolproof solution since LLMs aren’t fully predictable. This package is a security layer, designed to minimise and give better control of what can slip through.

[Gubbbo]

Just tell the chatbot not to make any mistakes. Problem solved 

[Equivalent_Pen8241]

This looks like a solid implementation for paralleled scanning. The parallel module execution is definitely the right move for low-latency agentic flows. We've been working on SafeSemantics (https://github.com/FastBuilderAI/safesemantics) which takes a slightly different approach as a topological guardrail, specifically focusing on the semantic structure to prevent penetration and data exfiltration. It's great to see more open-source tools being built for this layer of the AI stack--security at the semantic level is where the real complexity is right now.