# Invariants * Custody separation: Borrower controls BTC. Lender controls funds. * Atomic alignment: EVM withdrawal and BTC unlock are coupled through `x` for the main path and `y` for the fallback path. `T` defines the default path. * Oracle minimization: No price feeds are required for liquidation. The Cosigner is liveness only. * Auditability: SPV proofs, EVM events, and disclosure of `x` or `y` are publicly verifiable. This time sequence avoids overlap with System Architecture. Architecture explains what components exist and how they are bounded. Lifecycle explains when and how they interact. --- # 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.on.nexus/hodifi/invariants.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.