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Keeping copy on-brand with templates and constraints
How Copylume uses templates and constraints to keep every suggestion consistent and on-brand.
Generic AI copy is easy; **on-brand** copy is hard. Copylume keeps suggestions aligned with your voice using **templates** and **constraints**.
## Templates
Templates define the _kind_ of copy. For example:
- **hero_title** — Short, punchy headline (e.g. 6–10 words). - **hero_subtitle** — Supporting line that builds trust or clarity. - **hero_cta** — Call-to-action button or link text (e.g. 2–4 words).
Each template can have default min/max length and style hints. When you call the API or use the widget, you pass `template` so the model knows what to generate.
## Constraints
Constraints tighten the output per request or per field:
- **minWords / maxWords** — Keep length in check (e.g. hero title 6–10 words). - **bannedWords** — Words that must not appear (e.g. “cheap”, “discount”). - **styleGuidelines** — Short instructions (e.g. “Avoid absolute claims.” or “Use a friendly, casual tone.”).
You can set defaults in your API or dashboard and override per field when embedding the widget.
## Why it matters
Without templates and constraints, you get one-off copy that might be fine once but drifts over time. With them, every suggestion stays within the guardrails you set — so you can ship faster without losing brand consistency.