Tyche Institute · attestable agency

Who said the agent could do that?

Your AI agent holds your keys, and every signature it produces verifies. So who checks it stayed inside the job you gave it? A correctly-signed action can still be an unauthorized action — and you can catch it.

The spectrum: presence → authority

Mechanism

Answers

Anchor

BotGuard

human / browser?

none

PAT

genuine device?

hardware

PACT

legit agent?

none

AEP

what, whose authority, in mandate?

issuer+TPM+scope

The attack matrix

tamper_fieldDENY:content_mutated

forge_rechainledger ok · aep_sig_invalid

forge_fullDENY:issuer_not_listed

swap_mandateDENY:aep_sig_invalid

strip_sigDENY:aep_sig_invalid

replayALLOW · then replayed

exceed_scopeDENY:scope_violation

$ verify.py samples/exceed-scope.aep.json → DENY:scope_violation

Correctly signed. Out of mandate. Rejected.

The agent is not its own judge.

Break it yourself.
github.com/tyche-institute/aep-sandbox
tyche.institute/lab/aep-ctf/

Anton Sokolov
Tyche Institute · Tallinn
youtu.be/IIFKBNXMdik