Date: August 13, 2026
The public evidence package is published at cybiont/device-presence-bound-record. It contains a retained signed record of one real AI response, a deliberately tampered copy of that record, the public trust material and the standalone verifier. It needs no account, GPU, network connection or live cybiont service.
From inside the repository, the two controls are:
cd device-presence-bound-v1
python3 standalone_verify.py valid
python3 standalone_verify.py tampered
The valid bundle passes. In the tampered bundle, the response text is changed and the
attacker-controlled receipt and package manifest are updated to agree with that change. It still
refuses at the signed payload binding, exits with status 2 and names
PAYLOAD_DIGEST_MISMATCH.
The verifier also reports the boundary of a pass. The record establishes device presence at authorisation; it does not establish workload execution, physical locality, continuous presence or any performance property. Firmware measurements were not appraised and revocation was not checked.