Lesson 1044 of 1596
Sanitizing Untrusted Input Before Agents Touch It
Strip and bound user-provided text and files before they reach an agent's planning loop.
Creators · Agentic AI · ~7 min read
The premise
Treat user input as hostile: enforce length, strip control sequences, label provenance, and isolate attachments before the agent reads them.
What AI does well here
- Cap input size before tokenization
- Tag user-vs-system content explicitly
- Quarantine attachments behind a tool, not inline
What AI cannot do
- Detect every prompt injection
- Make the model immune to instruction following
- Replace authorization checks
Key terms in this lesson
Practice this safely
Use a small project example from your own work. The useful move is to compare the AI's draft against your goal, sources, and constraints before you trust it.
- 1Ask AI to explain input sanitization in plain language, then underline anything that sounds uncertain or too broad.
- 2Give it one detail from "Sanitizing Untrusted Input Before Agents Touch It" and ask for two possible next steps plus one reason each step might be wrong.
- 3Check prompt injection against a trusted source, teacher, adult, expert, or original document before you use it.
End-of-lesson quiz
Check what stuck
10 questions · Score saves to your progress.
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