Prd Writing

Write PRDs that are evidence-first, concise, and scannable. A PRD is a thinking tool — if it's longer than 1200 words, the author hasn't thought hard enough. Brief specs are more likely to be read, more likely to be followed, and more likely to ship on time.

Structure

Follow this structure. Every section is mandatory unless marked optional.

1. Problem

Lead with customer evidence. Quotes, data, support tickets, observed behavior. If you have no evidence, say so explicitly — that's an opinion-driven PRD and should be flagged.

Example: > "3 of 5 interviewed customers abandon onboarding at the team invite step. Average time spent: 47 seconds before closing the tab."

NOT: "Users find onboarding confusing."

2. Goals

Measurable outcomes, not outputs. Each goal has a number attached.

• "Reduce onboarding drop-off from 60% to under 30%"
• NOT "Improve the onboarding experience"

3. Target Users

Who specifically benefits. Be narrow. "Series A startup founders doing PM work before their first PM hire" — not "product managers."

4. Requirements

Use P0/P1/P2 with clear definitions:

• P0 — Does not ship without it. The feature is broken or useless without this.
• P1 — Ships without it, but significantly degraded. Do in same cycle if possible.
• P2 — Nice to have. Candidate for fast follow.

Each requirement is one sentence. If a requirement needs a paragraph to explain, it's too big — break it down.

5. Success Metrics

Numbers. Always numbers. "Reduce X from Y to Z within W weeks."

ALWAYS pair each metric with a counter-metric to prevent gaming:

• Metric: "Increase activation rate to 70%"
• Counter-metric: "Without decreasing 30-day retention below 45%"

6. Out of Scope

What you are deliberately NOT building and why. This section prevents scope creep and signals that you've thought about boundaries.

7. Open Questions (optional)

Unresolved decisions that need input. Each question names who should answer it and by when.

Guidelines

• CRITICAL: 800-1200 words maximum. Longer PRDs mean the thinking isn't done.
• NEVER start from a solution. Start from a problem with evidence.
• NEVER include implementation details — architecture, APIs, database schemas. That's spec territory, not PRD territory.
• ALWAYS include Out of Scope. A PRD without boundaries invites scope creep.
• ALWAYS trace requirements to customer evidence. No evidence = opinion.
• NEVER use weasel metrics: "improve performance," "enhance experience," "increase engagement." Put a number on it or don't include it.
• P0 requirements should number 3-5. If you have more than 5 P0s, you haven't prioritized.

Example: Good vs Bad

Bad P0 requirement: > "The system should handle authentication in a secure and user-friendly manner, supporting multiple providers and edge cases."

Good P0 requirement: > "P0: User can sign up and log in with email + password. Google OAuth is P1."

One sentence. Clear scope. Priority forces a decision.

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Built on Linear's "short specs > exhaustive docs" philosophy. Skills from productskills.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: assimovt
• Source: assimovt/productskills
• License: MIT

Install and usage instructions live in the source repository linked above.