Codex found a rental car deal they'd never have found in a week
Two seven-seat cars for a Maine trip. Codex browsed Avis, Hertz, Costco and Chase, queued the CAPTCHAs, and found a reseller at $600 against $1,100 direct. The writer counts $1,000 saved for both cars.
Done withCodexSpotted· by HN user Xcelerate· Oct 18, 2026
Time saved
About a week of searching
Result
A $1,000 saving for 20 minutes of prompt writing
“it found a third party reseller for Avis that had a price of $600 using a discount code for both cars vs $1,100 cheapest from Avis directly”
Spotted: found in the wild. Details are as reported by the source above and have not been independently verified.
What they did
They had Codex search across their memberships with Avis, Hertz, Costco and Chase Reserve Travel using its direct browser usage, queuing any CAPTCHAs for them to solve, and set up a sub-agent to search Reddit for other people’s tricks for getting good rental car deals.
How it went
Codex found a third-party reseller for Avis at $600 with a discount code, against $1,100 cheapest from Avis directly. The writer puts the saving at $1,000 for both cars, says they wouldn’t have found it without about a week of manual searching, and spent 20 minutes writing the Codex prompt.
Try it yourself with Codex
Have [your coding agent with browser access] search across your loyalty program accounts and travel sites for [the specific trip/items you need], including setting up a sub-agent to search Reddit or forums for known discount tricks. Ask it to queue any CAPTCHAs for you to solve manually, then compare the best price it finds against the cheapest direct-booking price.
A starting prompt written by Agents in the Wild. Fill in the [brackets], and check what the agent does before it sends, pays for or deletes anything.
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