Lesson 1467 of 2116
Sanitizing Untrusted Input Before Agents Touch It
Strip and bound user-provided text and files before they reach an agent's planning loop.
Lesson map
What this lesson covers
Learning path
The main moves in order
- 1The premise
- 2input sanitization
- 3prompt injection
- 4size limits
Concept cluster
Terms to connect while reading
Section 1
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
End-of-lesson quiz
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