What problem does it solve? Security reviews often produce generic threat lists or stale documents because teams skip drawing trust boundaries, assigning dispositions, or closing the loop with tests. This Skill provides a rigorous, repeatable methodology for identifying, prioritizing, and mitigating security threats at design time. ## Core Features & Use Cases - Four-Question Framework: Walks through what you are building, what can go wrong, what you will do about it, and whether you did a good job. - DFD and Trust Boundary Analysis: Maps external entities, processes, data stores, and flows with explicit trust boundaries including tenant, vendor, and CI/CD edges. - STRIDE Per Element: Applies the correct STRIDE categories to each diagram element using the standard element-to-category mapping, with worked threat tables. - Use Case: When designing a multi-tenant SaaS API, use this Skill to produce a data flow diagram, enumerate sixteen concrete threats with dispositions and owners, prioritize them on a likelihood-by-impact grid, and link each mitigation to a ticket and a regression test. ## Quick Start Ask the assistant to threat model your system architecture using STRIDE and data flow diagrams with trust boundaries.
