> ## Documentation Index > Fetch the complete documentation index at: https://resend.com/docs/llms.txt > Use this file to discover all available pages before exploring further. # Introduction > A collection of answers to frequently asked questions. ## Domains & Verification Add DNS records without conflicting with existing MX records. What to do when your domain isn't verifying. ## DNS Guides Step-by-step instructions for verifying your domain with popular DNS providers. } href="/knowledge-base/cloudflare" /> } href="/knowledge-base/gandi" /> } href="/knowledge-base/godaddy" /> } href="/knowledge-base/dreamhost" /> } href="/knowledge-base/hetzner" /> } href="/knowledge-base/hostinger" /> } href="/knowledge-base/ionos" /> } href="/knowledge-base/namecheap" /> } href="/knowledge-base/porkbun" /> } href="/knowledge-base/route53" /> } href="/knowledge-base/squarespace" /> } href="/knowledge-base/strato" /> } href="/knowledge-base/vercel" /> ## Deliverability Learn how to improve inbox placement in Gmail. Troubleshoot emails landing in spam or getting quarantined. Discover why sending emails from a subdomain can be better than using a root domain. Learn why your emails land on the suppression list, and how to remove them. Learn how to warm up your domain and dedicated IP for optimal deliverability. ## Sending Understand the sending quotas and rate limits for your Resend account. Learn how Dedicated IPs work and how to request them. Find the right Resend feature for your email sending use case. Learn when to add unsubscribe links to your transactional and marketing emails. ## Tutorials Everything you should do before sending authentication emails with Resend and Supabase. Display your brand logo in the Apple Mail inbox. Learn how to show your avatar in the inbox of your recipients. Set up email forwarding using Resend's inbound email processing. Author email templates as React components and upload them to Resend with the CLI. Add the open-source visual email editor to your own application. ## Troubleshooting Recommended options to avoid CORS errors when sending emails. Resolve 403 errors when the sending domain doesn't match your verified domain. Resolve domain ownership conflicts when a domain is already registered. Steps to take when an email is delivered but the recipient hasn't received it. ## AI Tools Everything you need to onboard your AI agent to Resend. Use Resend's Model Context Protocol server to send emails from AI tools. Skills for AI agents to build production-ready email systems with Resend. Skills for AI agents to build HTML emails using React components with Resend. Skills for AI agents to send emails with Resend. ## Account Management Learn more about Resend's pricing plans. Learn how to permanently delete your Resend account and data. Best practices for managing and securing your Resend API keys. ## Testing Set up end-to-end email testing with Playwright and Resend. Use Resend's test email addresses to simulate different delivery scenarios.