> For the complete documentation index, see [llms.txt](https://futaba.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://futaba.gitbook.io/docs/protocol/relayer.md). # Relayer Relayers act as intermediaries between the source chain and the destination chain. Their main functions are as follows: * Monitor and receive query requests emitted from the [Gateway Contract](/docs/protocol/gateway.md) on the source chain * Obtain proof based on the query requests * Use `eth_getProof` to obtain account proof and a storage proof * Send the proof as a transaction to the [Gateway Contract](/docs/protocol/gateway.md) on the source chain Today, Futaba operates its own Relayer. In the future, we will provide a module to customize Relayer more easily to support Proof of Block Hash when using [Konoha](/docs/protocol/konoha.md), and aim to build a Permissionless Relayer. The current Fee for Relayer can be found in [Estimate fee](/docs/protocol/light-client/estimate-fee.md). --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## 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, and the optional `goal` query parameter: ``` GET https://futaba.gitbook.io/docs/protocol/relayer.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. 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.