Web Skills

Overview of all Horizon skills for website creation and management — create, update, retrieve, and list sites through natural conversation.

Horizon provides four skills for creating and managing websites. These skills let agents build complete websites from HTML/CSS/JS, update existing sites, fetch external page content, and list all sites owned by a user — all through natural conversation.

Prerequisites

Web skills are available to all workspaces by default and do not require an external connection. Sites are hosted on Horizon’s infrastructure using Supabase storage. Agents must have the web skill category enabled in their configuration to invoke these skills.

Key concepts

Web skills share several common patterns:

  • Site ownership — every site is associated with the user who created it. Only the owning user (or their agents) can update or manage the site.
  • Storage-backed hosting — HTML, CSS, and JS files are uploaded to Supabase storage and served via a public URL. Sites are statically hosted and do not support server-side rendering.
  • SSRF protection — the Retrieve Site skill enforces strict protections against server-side request forgery, including blocking private IP ranges and internal hostnames.
  • Sanitization — retrieved HTML content is sanitized to remove potentially dangerous elements before being returned to the agent.

Available skills

Common workflows

Agents frequently chain Web skills together. A typical workflow might look like:

  1. Retrieve Site to fetch an external page the user references as inspiration.
  2. Create Site to build a new site based on that reference.
  3. List Sites so the user can review all their sites.
  4. Update Site (fetch mode) to pull back the source code, then Update Site (update mode) to push changes.

Related: Creating Agents