Custom Domains
Custom Domains let you map your own domain names (e.g., mcp.example.com, webhook.example.com) to your Hot Dev environment. Instead of your customers connecting to api.hot.dev, they connect to your branded domain.
Pro plan required. Custom domains are available on Pro and Scale plans. If you're on the Starter plan, the Domains page shows an upgrade prompt.
Plan limits: Pro allows up to 5 custom domains per organization, Scale up to 25, and Self-Host is unlimited.
Multiple domains can be mapped to the same environment - for example, mcp.example.com and webhook.example.com can both route to the full API surface.
Adding a Domain
Click Add Domain in the Hot App and enter your domain name. Hot Dev will request a TLS certificate from ACM (AWS Certificate Manager) and begin provisioning.
The domain detail page guides you through three steps:
- Request Certificate - Hot Dev requests a TLS certificate from ACM automatically. DNS validation records appear within a few seconds.
- Validate & Issue - Add the ACM validation CNAME record shown on the detail page (e.g.,
_abc123.mcp.example.com -> _xyz789.acm-validations.aws) to prove domain ownership. Once DNS propagates, the certificate is issued. - Domain CNAME - Once the certificate is validated, a CloudFront distribution is created automatically. Add a CNAME pointing your domain to the distribution (e.g.,
mcp.example.com -> d1234abcdef.cloudfront.net). This record appears once provisioning completes.
The detail page updates automatically - you can leave it open and watch each step progress without refreshing.
Verification & Status
Click Check Status on the domain detail page to trigger an immediate recheck. When a CloudFront distribution exists, Check Status also performs a live DNS lookup to verify your domain's CNAME record is pointing to the correct distribution.
You don't have to keep clicking Check Status - pending domains are also checked automatically in the background. Once DNS propagation completes, your domain will be validated and provisioned without any manual action.
| Status | Meaning |
|---|---|
| Pending Validation | ACM validation CNAME not yet detected |
| Validated | ACM certificate issued, CloudFront provisioning in progress |
| Provisioning | CloudFront distribution being created or deployed |
| Active | HTTPS is active - domain CNAME is configured and routing traffic |
| Deleting | Domain removal in progress - AWS resources are being cleaned up |
Using Custom Domains
Once a domain is active, use it anywhere you'd use api.hot.dev:
- MCP endpoints - Point AI agents to
mcp.example.cominstead ofapi.hot.dev - Webhook URLs - Give external services your branded webhook URL
- API calls - Use your domain for all Hot API requests
The domain routes to the same Hot API surface, so all existing API keys, MCP services, and webhooks work automatically.
Removing a Domain
Click Remove Domain on the domain detail page to delete a custom domain. This soft-deletes the domain and queues cleanup of the associated AWS resources (CloudFront distribution and ACM certificate).
While cleanup is in progress, the domain shows a Deleting status. You cannot re-add the same domain name until cleanup completes - attempting to do so will show a message asking you to wait.
When removing a domain, remember to also delete the DNS CNAME records you created for it (both the ACM validation CNAME and the domain CNAME).
API Access
Custom domains can also be managed programmatically via the Custom Domains API.