A Practical Guide to Dynamic Variables in Prompts

A static prompt answers one question. A templated prompt answers a hundred. The trick is variables — placeholders you fill in at send time. Here are the five types and when to reach for each.

1. Free text — {{Recipient}}

The everyday workhorse. Use it for names, topics, short phrases.

2. Multi-line text — {{...Context}}

When the input is a paragraph — background, a snippet of an article, meeting notes — give yourself room to type.

3. Number — {{#Count}}

For quantities and limits: "Give me {{#Count}} ideas." Keeps the model from guessing how many you want.

4. Single select — {{formal|casual|neutral}}

When there's a fixed set of choices, a dropdown beats free text. No typos, no ambiguity.

5. Multi select — {{+Python|Java|TypeScript}}

Pick several at once. Perfect for "Review this code in {{+Python|Java}}."

The payoff

Write the prompt once, fill the form, send. The same Code Review prompt now works for every language and every file — no rewriting, no hunting through history.