Provider credentials

Credentials belong in the server process that constructs the adapter. Email SDK does not read a universal configuration file or expose credentials to browser code.

Required environment variables

Run the adapter catalog to see the names required by the bundled CLI.

npx email-sdk adapters

Common adapters use these values:

The adapter pages list every credential and adapter-specific option.

Pass credentials to application code

Adapter factories accept credentials explicitly. Environment variable names are a deployment convention rather than a hidden SDK lookup.

import { resend } from "@opencoredev/email-sdk/resend";

export const resendAdapter = resend({
  apiKey: process.env.RESEND_API_KEY!,
});

Check configuration

doctor checks whether the CLI has enough values to construct the adapter. It does not prove that a credential is accepted by the provider.

RESEND_API_KEY=re_xxx npx email-sdk doctor --adapter resend

Use send --dry-run to validate a full message without network delivery. Use a real send only with an approved test recipient.

SMTP transport security

SMTP auth on a non-secure port requires TLS. The transport upgrades with STARTTLS by default. Set allowInsecureAuth only for a trusted local test server.