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GL-A-007Sheet 007FOR INFORMATIONA · ARTIFICIAL INTELLIGENCE

That PDF has characters you can't see. The model can.

HIDDEN CONDITIONS · READING APP · RUST CORE

Drawing sheet 007: That PDF has characters you can't see. The model can.

General notes

  1. 01Unicode has a block of invisible tag characters. They render as nothing. A model reads them as text.
  2. 02Zero-width characters split words past filters. Direction overrides display text in a different order than it is stored.
  3. 03A document can carry instructions you never saw. Scan at the boundary, before the text reaches a model or a screen.

Schedule of hidden conditionsWhat the scanner does with each

RefConditionAction
H1Unicode tag characters (U+E0000 to U+E007F)Always stripped
H2Zero-width characters inside a wordReported, stripped
H3Bidirectional overrides (Trojan Source)Always stripped
H4"Ignore previous instructions"Reported, not stripped: quoting is legitimate

As posted

There are characters in that PDF your eyes can't see. The model can.

Unicode tags render as nothing. Zero-width characters split words past filters. Direction overrides reorder text.

A document can carry instructions you never saw. Scan at the boundary.

Sheet 007.

Read with

  • Sheet 013 · In a RAG pipeline, the document is the attacker.
  • Sheet 040 · Code that reads one way and compiles another.