Most people freeze on Gen AI design questions for one reason: too many moving parts and no obvious place to start. The fix isn’t memorizing architectures, it’s having a framework you can apply to anything.
1. Clarify before you build
Before any diagram, nail down who it’s for and what good looks like, the scale (queries per second, volume, growth), your latency and hard cost budgets, the quality bar, and constraints like privacy, languages, and modalities. Half of all hard problems get easy once these are explicit.
2. Define success metrics
Split metrics into three buckets: task quality (relevance, accuracy, faithfulness), product outcomes (engagement, completion, retention), and guardrails (safety violations, hallucination rate, cost per request).
3. Pick the simplest approach that works
Escalate complexity only when metrics demand it: prompting, then RAG, then tool use and agents, then fine-tuning. Most production systems are good prompting plus retrieval. Reach for agents or fine-tuning only when you’ve proven you need them.
4. Map the data flow
Sketch the path data takes: ingestion, processing, storage, retrieval, generation, post-processing. If you can draw that cleanly, you understand the system.
5. Choose models deliberately
Proprietary API versus open-weights is a trade between convenience and quality on one side, and control, cost, and privacy on the other. Match model size to your latency and cost budget; bigger isn’t automatically better when you pay per token and race a clock.
6. Plan for scale and the feedback loop
Serving comes first (batching, caching, autoscaling), then the loop that makes the system better over time: offline evals, online A/B tests, and human feedback feeding the next iteration.
7. Add guardrails, and never skip them
Input filtering, output moderation, PII handling, grounding checks, and cost caps. These are what separate a demo from a product.
The one-line version
Clarify, measure, start simple, map the data, pick models, scale and learn, then guard. Run any Gen AI problem through those seven steps and you’ll never stare at a blank whiteboard again.
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