> For the complete documentation index, see [llms.txt](https://zkcross-network-1.gitbook.io/learn.zkcross.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://zkcross-network-1.gitbook.io/learn.zkcross.network/security-and-control/signing-and-permissioning.md). # Signing and Permissioning Deterministic rules define what is allowed. Signing defines what is physically possible. zkCross treats signing as a controlled permission surface rather than as a generic execution key. ### Permissioned signing Only policy-compliant actions can reach the signing path. The signing model is designed so that: * approval is scoped to allowed actions, targets and parameters * keys are never exposed in application logic * signatures cannot authorise arbitrary execution outside approved action sets * privileged operations can require stronger approval conditions Where appropriate, zkCross uses MPC-based signing. In non-EVM contexts such as ICP, decentralised signing primitives can be used while preserving the same high-level security model. The important architectural point is that signing remains downstream of policy validation. Guardian approval without valid signing is insufficient. Signing without policy compliance is impossible. That separation prevents permission escalation through hidden call paths or loosely scoped authorisation. --- # 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://zkcross-network-1.gitbook.io/learn.zkcross.network/security-and-control/signing-and-permissioning.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.