domain

Domain Management

Add, view, or remove domains for Railway services.

When to Use

• User asks to "add a domain", "generate a domain", "get a URL"
• User wants to add a custom domain
• User asks "what's the URL for my service"
• User wants to remove a domain

Add Railway Domain

Generate a railway-provided domain (max 1 per service):

railway domain --json

For a specific service:

railway domain --json --service backend

Response

Returns the generated domain URL. Service must have a deployment.

Add Custom Domain

railway domain example.com --json

Response

Returns required DNS records:

{
  "domain": "example.com",
  "dnsRecords": [
    { "type": "CNAME", "host": "@", "value": "..." }
  ]
}

Tell user to add these records to their DNS provider.

Read Current Domains

Use environment skill to see configured domains, or query directly:

query domains($envId: String!) {
  environment(id: $envId) {
    config(decryptVariables: false)
  }
}

Domains are in config.services.<serviceId>.networking:

• serviceDomains - Railway-provided domains
• customDomains - User-provided domains

Remove Domain

Use environment skill to remove domains:

Remove custom domain

{
  "services": {
    "<serviceId>": {
      "networking": {
        "customDomains": { "<domainId>": null }
      }
    }
  }
}

Remove railway domain

{
  "services": {
    "<serviceId>": {
      "networking": {
        "serviceDomains": { "<domainId>": null }
      }
    }
  }
}

Then use environment skill to apply and commit the change.

CLI Options

Flag	Description
[DOMAIN]	Custom domain to add (omit for railway domain)
-p, --port <PORT>	Port to connect
-s, --service <NAME>	Target service (defaults to linked)
--json	JSON output

Composability

• Read domains: Use environment skill
• Remove domains: Use environment skill
• Apply removal: Use environment skill
• Check service: Use service skill

Error Handling

No Service Linked

No service linked. Use --service flag or run `railway service` to select one.

Domain Already Exists

Service already has a railway-provided domain. Maximum 1 per service.

No Deployment

Service has no deployment. Deploy first with `railway up`.

Invalid Domain

Invalid domain format. Use a valid domain like "example.com" or "api.example.com".