> For the complete documentation index, see [llms.txt](https://crosschain-alliance.gitbook.io/hashi/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://crosschain-alliance.gitbook.io/hashi/getting-started/quick-start/verifying-foreign-event.md).

# Verifying foreign event

This example demonstrates the validation of a `Transfer` Event from an ERC-20 contract on the Sepolia network using an event proof on the Chiado network. The proof is retrieved via an API call and provided to a custom contract to be deployed on Chiado. The contract utilizes the `HashiProver` helper library to verify the proof against the latest block header recorded in Hashi.

<figure><img src="https://1891280734-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F61xOMwWistUayaApyKG0%2Fuploads%2FqyHu7U4VOTODciIXH8gj%2FStateVerifying.png?alt=media&amp;token=9dee6979-5388-481c-b72f-816459427a6a" alt=""><figcaption></figcaption></figure>


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