fix header

Author: elithrar

src/content/docs/agents/index.mdx

@@ -24,7 +24,7 @@ import {
 
 <Plan type="all" />
 
-Build AI-powered agents that can autonomously perform tasks, persist state, browse the web, and communicate back to users in real-time over any channel.
+**Build AI-powered agents that can autonomously perform tasks, persist state, browse the web, and communicate back to users in real-time over any channel.**
 
 Agents are deployed to Cloudflare's [Workers](/workers/) platform using [Durable Objects](/durable-objects/), [Browser Rendering](/browser-rendering/), [Email Routing](/email-routing/) and [more](/products/?product-group=Developer+platform).