PRD (Product Requirements Document)
A PRD (Product Requirements Document) defines what a product or feature should do and why — the problem, the users, the requirements, scope, and success metrics — so design and engineering can build the right thing.
A PRD is the shared source of truth for a piece of product work. It typically covers the problem and its evidence, target users, prioritized requirements, scope and non-goals, dependencies and risks, and how success will be measured.
A good PRD is decision-oriented, not a wish list: it makes the trade-offs explicit (what is in v1 and what is deferred, and why). It should stay connected to the research it rests on and the prototype it describes, so it does not rot as the product changes.
Instead of "the app should be fast," a PRD states a testable requirement: "Search results return in under 500ms for 95% of queries," with the rationale and how it will be measured.
ArcPM generates a build-ready PRD as the final stage of its flow, and keeps it linked to the requirements and prototype it came from — so when a requirement changes, the affected PRD sections are flagged rather than left stale.
See ArcPM