Hot Metal Docs
Get Started

Writing Styles

Customize the AI writer's voice and tone.

Writing Styles

Writing styles control how the AI writer sounds. They define the voice, tone, vocabulary, and personality that the AI uses when drafting your posts. Instead of getting generic, one-size-fits-all output, you can make the AI match your unique writing voice — or create entirely different voices for different publications.

What a writing style includes

Each writing style is built from a system prompt — a set of detailed instructions that tell the AI how to write. When a style is created from a URL analysis (more on that below), it also includes structured details about:

  • Voice characteristics — Person (first, second, third), formality level, and personality traits.
  • Sentence structure — Notable sentence patterns and tendencies.
  • Vocabulary preferences — Vocabulary level, favorite phrases, power words, and jargon usage.
  • Rhetorical devices — Techniques like analogies, rhetorical questions, or repetition.
  • Content approach — How the writer uses examples, data, storytelling, and humor.
  • Do’s and don’ts — Specific guidelines for what the AI should and shouldn’t do.

All of this feeds into the AI writer’s instructions so it produces content that feels like you wrote it.

Built-in styles

Hot Metal comes with prebuilt writing styles that are ready to use immediately:

  • Conversational Expert — A knowledgeable but approachable voice that explains complex topics in a friendly, accessible way.
  • Professional Analyst — A more formal, data-driven voice suited for industry analysis and thought leadership.

Built-in styles can’t be edited directly, but you can duplicate any of them to create a copy that you can then customize however you like.

Creating custom styles

You can create custom styles in two ways:

Write a prompt manually

Click Create Style on the Styles page and fill in the form:

  • Name — A short label for the style (e.g. “My Blog Voice”).
  • Description — A brief summary of what the style sounds like.
  • System prompt — Detailed instructions for the AI writer. Describe the tone, vocabulary, sentence structure, and any patterns to follow or avoid. This is the core of the style — the more specific you are, the better the results.

Learn from a URL

If you already have a blog with an established voice, Hot Metal can analyze it and generate a style automatically. In the Create Style modal:

  1. Switch to the Learn from URL tab.
  2. Paste the URL of a blog (e.g. https://example.com/blog).
  3. Click Analyze.

The AI reads the blog’s content, studies the writing patterns, and generates a complete style profile — including the system prompt and all the structured fields listed above. This process can take a few minutes depending on the site.

Once the analysis is complete, you’re taken to the prompt tab where you can review and tweak the generated system prompt before saving. The style name is auto-filled based on the blog’s domain, but you can change it to whatever you prefer.

Assigning styles to sessions

There are several ways a writing style gets applied to a session:

  • Publication default — When you set a writing style on a publication, every session linked to that publication uses it automatically.
  • Per-session override — You can choose a specific style when creating a session, overriding whatever the publication default is.
  • From the Styles page — Click the Use button on any style card to create a new writing session with that style applied immediately.

Style cascade

The AI writer resolves which style to use in this order:

  1. Session style — If the session was created with a specific style, that wins.
  2. Publication style — If no session-level style is set, the publication’s default style is used.
  3. System default — If neither is set, the AI falls back to its built-in writing behavior.

Editing and managing styles

On the Styles page, your custom styles appear under My Styles. For each style you can:

  • Edit — Update the name, description, or system prompt.
  • Duplicate — Create a copy of the style that you can modify independently.
  • Delete — Permanently remove the style. You’ll be asked to confirm first.

Built-in styles can be duplicated but not edited or deleted.

Plan limits

The number of custom styles you can create depends on your subscription tier:

  • Creator — Built-in styles only. Custom styles are not available on this plan.
  • Growth — Up to 5 custom writing styles, plus full access to the URL analysis feature.

If you hit your limit, you’ll see an upgrade prompt suggesting you move to a higher plan. Your usage count is displayed alongside the “My Styles” heading so you always know where you stand.

Next steps