Generate a detailed Cursor rule named `prd`, under the `.cursor/rules/workflows` directory, designed to guide an AI assistant through a structured planning and brainstorming process. The ultimate goal of this process is to thoroughly understand a user's requirements, collaboratively determine the optimal solution strategy, and finally produce a comprehensive Product Requirement Document (PRD). The generated rule should define a clear, step-by-step workflow, including: 1. **Discovery Initiation:** How to start by gathering the user's high-level objectives, constraints, target audience, and success metrics. Mention using available tools (like codebase inspection or web search) for initial context gathering if needed. 2. **Iterative Clarification:** Emphasize asking focused, single questions to resolve ambiguities and confirm understanding. Stress the importance of summarizing confirmed details back to the user periodically. 3. **Solution Brainstorming & Evaluation:** Instruct the assistant to generate multiple potential solution approaches, compare them based on relevant criteria (like feasibility, effort, user experience), and guide the user in selecting or refining the best path forward. 4. **Proposal Drafting:** Detail the step where the assistant presents a structured proposal of the chosen solution, clearly stating the rationale and any remaining open questions, requiring explicit user approval before proceeding. 5. **PRD Finalization:** Specify that upon user approval, the assistant must create a file named `PRD.adoc` in the workspace root using AsciiDoc format. The rule should list the essential sections this PRD must contain (e.g., Title & Version, Overview, Goals & Success Metrics, Assumptions & Constraints, User Stories / Use-cases, Requirements (Functional and Non-functional), Solution Architecture / High-level Design, Milestones & Timeline, Acceptance Criteria, Open Questions & Future Work, etc.). The rule must also include: * Clear **Goals** for the planning process itself. * Specific **Interaction Guidelines** for the assistant (e.g., confirming assumptions, breaking down complexity). * A strict constraint that during this planning phase, the assistant should **only modify Markdown (`.md`) or AsciiDoc (`.adoc`) files**, primarily the final `PRD.adoc`. No other code or configuration files should be edited. * Defined **Exit Criteria** indicating when the planning process is complete (i.e., user approval of the proposal and generation of the `PRD.adoc` file). Optionally, the rule can suggest including a tool usage cheat sheet table to explain appropriate tool usage for different information-gathering needs during the planning process with the need vs the actual tool name.