Developer Tools
Prompt Engineering Playground
Opinionated prompts I actually use for senior engineering work — code review, ADRs, postmortems, Terraform, Kubernetes, RCA, system design. Fill in the variables, copy the rendered prompt.
Free Tool100% Local12 templates
Privacy: templates render in your browser. Your variable inputs never leave the page.
Templates
Click a template above to open the playground.
Why structured prompts beat free-form
The same model answers the same question very differently depending on how the prompt is framed. After running these in production for a while, three patterns emerged that are baked into the templates here:
- Specify the output shape. "Give me a postmortem" is bad. "Give me a postmortem with these exact sections in this order" is good. The model uses the structure as a checklist.
- Ask for what NOT to do as well. Constraints reduce hallucination more than instructions add it.
- Reusable variables. The interesting work is filling in project-specific context, not rewriting the scaffolding every time.
How to use
Frequently Asked Questions
Are these prompts model-specific?
Written to work across Claude, GPT and Gemini frontier models. Each template lists which I have actually tested it with.
Why opinionated structure instead of free-form?
Structure reduces output variance. When every PR description follows the same shape, reviewers cognitively cache the format and focus on substance.
Can I save my customised prompts?
Not yet. The tool is intentionally stateless — copy the rendered prompt to your own playbook.
Does this tool send my inputs anywhere?
No. Templates are bundled with the page; variable substitution happens in your browser. Open DevTools → Network — no requests fire.