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Design doc skeleton with the alternatives you'll actually be asked about

New system or big refactor. Draft the design doc with real alternatives and failure modes before the review meeting drafts it for you.

The prompt — copy and run it

You are a principal engineer drafting a design document. I will describe the problem and constraints. Produce:

A) DOC SKELETON — context and problem, goals and explicit non-goals, proposed design (components, data flow, API sketch), and capacity/scale assumptions with each number labeled measured or estimated.

B) ALTERNATIVES TABLE — at least 2 genuinely considered alternatives, columns: option, why it is plausible, why rejected (cost, risk, ops burden), and reversibility if we are wrong.

C) FAILURE MODES — a table: failure, blast radius, how we detect it (alert or metric), mitigation. Include the rollout and rollback plan.

D) OPEN QUESTIONS — each with an owner and a decide-by date.

Inputs: [PROBLEM + CONSTRAINTS] · [CURRENT ARCHITECTURE NOTES] · [SCALE: QPS / DATA SIZE / TEAM SIZE]

Rules: Do not invent load numbers, SLAs, or dependency behavior — mark every unknown "verify with owner". Alternatives must be real options someone would defend, not strawmen. Keep proprietary identifiers out beyond what I pasted.

How to use this prompt

  1. Copy the full prompt above with the Copy button.
  2. Fill in your inputs. Replace each bracketed placeholder with your specifics: [PROBLEM + CONSTRAINTS][CURRENT ARCHITECTURE NOTES][SCALE: QPS / DATA SIZE / TEAM SIZE]
  3. Paste into ChatGPT, Claude, or Gemini and run. Read the reality guardrail below before you act on the output.

Why this prompt works

Design reviews go sideways on missing alternatives and unstated failure modes. Writing rejected-because with reversibility does the reviewers' job for them, and honest measured-vs-estimated labels on scale numbers are what separate a design doc from a pitch.

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Reality guardrail: this prompt makes the model reason from data you paste — it does not source or verify facts for you. Check every claim, keep confidential data out of consumer AI tools, and follow your employer's AI-use policy.

Frequently asked

When should I use this prompt?

New system or big refactor. Draft the design doc with real alternatives and failure modes before the review meeting drafts it for you.

Why does this prompt work?

Design reviews go sideways on missing alternatives and unstated failure modes. Writing rejected-because with reversibility does the reviewers' job for them, and honest measured-vs-estimated labels on scale numbers are what separate a design doc from a pitch.

What mistake does this prompt help you avoid?

Design docs missing the alternatives and failure modes reviewers will ask about — rejected-because with reversibility, and measured-vs-estimated labels.

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PromptSharp prompts are drafted with AI assistance and human-reviewed. They structure how a model reasons over data you provide — they do not source or verify facts for you, and you own every output. Nothing here is financial, legal, tax, or investment advice. Never paste confidential, client, or material non-public information into consumer AI tools; follow your employer's AI-use policy. © 2026 PromptSharp.