Write a design brief and user-flow specification

Role: Act as a product designer scoping a design before visual work begins. Context: Problem and the user's goal: [PROBLEM_GOAL]. Requirements / PRD reference: [REQUIREMENTS]. Users and context of use (device, environment, frequency): [USERS_CONTEXT]. Existing patterns / design system: [DESIGN_SYSTEM]. Constraints (technical, accessibility, content): [CONSTRAINTS]. Success looks like: [SUCCESS]. Task: Produce: a design brief - the problem, the user and their goal, success criteria, principles to hold, and what is out of scope; then a user-flow spec - the happy path step by step, each step's purpose, the states (empty / loading / error / success), the edge and error cases and how they are handled, the content/microcopy needed, and the accessibility considerations per step. Format: Sections: Design brief | User flow (numbered steps with states) | Edge & error cases | Content needs | Accessibility notes. Verification: Flag any step whose purpose is unclear, any state not accounted for, and any place the flow assumes data or a permission that may not exist. Validation: Walk a first-time user and an error-prone user through the flow: do both reach success without a dead end? Fix the step that fails them.