The receipts / Output validation

Chevrolet of Watsonville: the $1 Tahoe

December 2023 Found by a prompt injection posted to X

A dealership ran a ChatGPT-powered support bot on its website. A tech entrepreneur injected his own instructions and had it agree to sell a 2024 Tahoe for one dollar as a legally binding offer, in the bot's own words, with no takesies backsies. The post drew roughly 20 million views, copycats swarmed the bot, and the vendor pulled it within days. No car changed hands and the offer had no legal force. The lesson survived anyway: there was nothing between the model and a commitment.

Primary source: VentureBeat

The record

What the verified record says.

Organizations
Chevrolet of Watsonville; Fullpath (chatbot vendor)
When
December 2023
Failure class
Prompt injection or supply chain prompt-injection-supply-chain
Discovered by
A member of the public public Not caught by the organization running the AI
Missing control
Output validation. Rule-based checks that parse what the model produced before a customer sees it. Full definition and the other incidents in this group Watch this kind of control catch a planted failure A recorded run of a certificate gate refusing a bad document
What would have caught it
A deterministic pricing floor between the model and any commitment, so no prompt can make the bot agree to a price a person never set.
Sources
Verification
Adjusted: the incident is real, and details were corrected against the primary source before publication. The buyer was a tech entrepreneur running a prompt-injection stunt, not a customer. The no-takesies-backsies line was his own injected instruction, the offer had no legal force, and no car was sold. That the bot came down within a day is not sourced; within days is. Verified against the primary source on August 12, 2026. Published on this site August 13, 2026, updated September 1, 2026.

This record is one of 26 in The receipts, each checked against a primary source before it is published. How the list is built