# Absurd Chainlink prices, weekend FX hours, and the breakers meant to catch both

Mentorship Series #8 · 17 December 2025 · [@0xfirefist](https://x.com/0xFireFist) · Mento V3 · Cantina

Mentorship Series · [The Contest Academy](https://0xsimao.com/the-contest-academy) · 0xSimao

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We continued the Mento V3 [contest](https://cantina.xyz/competitions/fe8e03b1-f8db-4698-8a21-44b3a862e434) on Cantina.

**Lesson Summary:**

- Can Chainlink return an absurd price? If so, it is recorded as `lastValidPrice`, which is a problem;
- What happens on weekends? It's a FX, so, will the protocol be shut down on weekends or what? - No valid price will be available, but the system will be \`live\`;
- Audit the whole adapter (as it's in-scope) and then get back to see if it makes any problem in the Bold part;
- Check market hours breaker - understand how it decides if the market should be closed or not;
- What is the trading mode?
- Study `BreakerBox`.

https://youtu.be/GlkrYG3Kcr8

Session video: https://youtu.be/GlkrYG3Kcr8

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Newer: [Keeping a bad price out of storage: expired reports and permissionless cleanup](https://0xsimao.com/the-contest-academy/mentorship-series-9) · Older: [Know the collateral: which price feed it needs, and manual versus automatic shutdown](https://0xsimao.com/the-contest-academy/mentorship-series-7)