> For the complete documentation index, see [llms.txt](https://surf-2.gitbook.io/surfliquid-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://surf-2.gitbook.io/surfliquid-docs/security-control-layer.md).

# 🔒 Security Control Layer

- [Guardian Layer Overview](https://surf-2.gitbook.io/surfliquid-docs/security-control-layer/guardian-layer-overview.md): Deterministic control for how Surf interacts with real capital
- [Deterministic Rules and Invariants](https://surf-2.gitbook.io/surfliquid-docs/security-control-layer/deterministic-rules-and-invariants.md)
- [Invariant Definitions](https://surf-2.gitbook.io/surfliquid-docs/security-control-layer/invariant-definitions.md)
- [Protocol Allowlist Criteria](https://surf-2.gitbook.io/surfliquid-docs/security-control-layer/protocol-allowlist-criteria.md)