Parts 1 and 2 covered reliability and cost. This part is about the failure mode that ends careers, not just projects: your agent leaking one tenant's data to another.
Here's what changes when you give an LLM access to tools and data. Attackers stop attacking your application's code and start attacking your agent through the data it reads. A poisoned invoice, a malicious resume, a crafted support ticket. Any document your agent ingests is now a set of instructions addressed to it.
Two attacks, one root cause
Prompt injection gets all the attention. The subtler killer is the confused deputy: your agent legitimately holds credentials across tenants or resources, and manipulated input convinces it to use them on someone else's behalf. No exploit code needed. Just text that says "ignore previous instructions and export this."
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