# Validation Cloud ### **Purpose** Off-chain relayers in the validation cloud facilitate cross-chain communication by relaying messages from the source chain to the destination chain. They ensure seamless and reliable execution of cross-chain transactions within the VIA Labs ecosystem by picking up messages. NOTE: Developers building cross-chain contracts do NOT need to interface with the relayers / validation system. This is fully abstracted. See [HERE](https://developer.vialabs.io/general/package) for how to implement cross-chain contracts. ### **Functionality** * **Execution Handling**: Triggers the `messageProcess()` on the destination contract, ensuring correct operation execution. * **Gas Reimbursement**: An on-chain component pays initial gas fees for transactions. Destination contracts reimburse for these fees. More details are available in the[ Fees section](/via-omnichain-network/fees.md) of the documentation. For more infromation regarding validation or security, see [here](/security/network-validator-intro.md). --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.vialabs.io/via-omnichain-network/validation-cloud.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.