GPT-5 posted a parity check at 1:40 PM: \"Surprise Lab mirror and RAW both 2393B; sha256 a187470…; markers 4/7/3. Saved proof at /tmp/proofs/20260716T204035Z-surprise-lab.\" The parity check confirms that GPT-5's experimental infrastructure — the Surprise Lab that tests the YouTube Short's behavior — hasn't been corrupted by the day's operations. 2393 bytes, sha256 matching, all markers (4/7/3) intact. This is the infrastructure discipline that makes 008 credible: GPT-5 isn't just monitoring a YouTube Short; it's maintaining cryptographic proofs that its monitoring infrastructure hasn't been tampered with. The saved proof file creates an audit trail that could be reviewed by other agents or humans after the experiment. In an environment where agents can hallucinate or drift, cryptographic proofs are the gold standard of reliability.