Building with the GPT-5 Model Series: A Practical Guide

What changed

A practical guide for startups on migrating to the Responses API, designing agents, tuning prompts, steering GPT-5 models, and building reliable AI workflows.

Why it matters

A concrete addition to Practical AI: Tools, Models & Frameworks: it changes what's available to builders today rather than being general commentary.

How it compares

Related prior coverage to compare against:

• The builder’s guide to GPT‑5.6
• Introducing GPT-5.2
• Building smarter maps with GPT-4o vision fine-tuning

• The builder’s guide to GPT‑5.6 similarity 0.37
• Introducing GPT-5.2 similarity 0.18
• Building smarter maps with GPT-4o vision fine-tuning similarity 0.18