> For the complete documentation index, see [llms.txt](https://docs.arcan.finance/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.arcan.finance/protocol/host.md). # Host chain Robinhood is the host. It is the ledger users already call. Arcan does not ask it to run fully homomorphic encryption. ## What Robinhood stores * Contract bytecode and the confidential token state * Handles in place of amounts * The access list: who may use or open each handle * The symbolic trace of each FHE operation ## What a node can answer A node can return the transaction, the sender, the recipient, and the handle. `confidentialBalanceOf` returns a handle. It does not return the decrypted balance to the RPC. An explorer can render the token symbol and `****` for the value. That is the honest public view. ## Symbolic execution The executor contract is the host component that applies FHE calls. It checks permissions, allocates the next handle, and logs the operation. It does not add the hidden integers. If the executor and the coprocessor ever disagree, the ciphertext committed by the coprocessor is recomputed from the trace. The handle on the host must match that recomputation. ## Addresses `ArcanConfig` is the single list of host addresses: access list, executor, and decryption verifier. Contracts inherit it. The input verifier address is read from the executor. --- # 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 following URL with the `ask` and `goal` query parameters: ``` GET https://docs.arcan.finance/protocol/host.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `build a script that syncs our docs to a CMS` lets GitBook tailor the answer to that use case. 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.