CLI

The CLI is intentionally small. Use it to inspect adapters, check environment variables, validate a message with --dry-run, and send a smoke-test email from your terminal.

The npm package is @opencoredev/email-sdk; the CLI command it installs is email-sdk.

Install or run

Run the CLI once with the scoped package:

npx --yes --package @opencoredev/email-sdk email-sdk adapters

Install the SDK in a project:

npm install @opencoredev/email-sdk

Then run the installed binary:

npx email-sdk adapters

Check the installed version before comparing behavior against the docs:

npx email-sdk version

The CLI supports Node 20+ and Bun 1.1+. The examples use npx because it is the broadest copy-paste path; Bun users can run the one-off CLI with bunx --bun --package @opencoredev/email-sdk email-sdk adapters.

Send

RESEND_API_KEY="re_..." npx --yes --package @opencoredev/email-sdk email-sdk send \
  --adapter resend \
  --from "Acme <hello@acme.com>" \
  --to "user@example.com" \
  --subject "Hello" \
  --text "It works"

Adapters

npx --yes --package @opencoredev/email-sdk email-sdk adapters

Adapter	Required environment
`resend`	`RESEND_API_KEY`
`postmark`	`POSTMARK_SERVER_TOKEN`
`sendgrid`	`SENDGRID_API_KEY`
`cloudflare`	`CLOUDFLARE_API_TOKEN`, `CLOUDFLARE_ACCOUNT_ID`
`ses`	`AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`, `AWS_REGION`
`mailgun`	`MAILGUN_API_KEY`, `MAILGUN_DOMAIN`
`mailersend`	`MAILERSEND_API_KEY`
`brevo`	`BREVO_API_KEY`
`mailchimp`	`MAILCHIMP_API_KEY`
`sparkpost`	`SPARKPOST_API_KEY`
`loops`	`LOOPS_API_KEY`, `LOOPS_TRANSACTIONAL_ID`
`plunk`	`PLUNK_API_KEY`
`mailtrap`	`MAILTRAP_API_KEY`
`scaleway`	`SCALEWAY_SECRET_KEY`, `SCALEWAY_PROJECT_ID`
`zeptomail`	`ZEPTOMAIL_TOKEN`
`mailpace`	`MAILPACE_API_KEY`
`smtp`	`SMTP_HOST`, plus SMTP auth variables when needed

If --adapter is omitted, the CLI selects the first adapter with all required environment variables set.

Doctor

RESEND_API_KEY="re_..." npx --yes --package @opencoredev/email-sdk email-sdk doctor --adapter resend

doctor checks whether the selected adapter has the required environment variables or matching CLI credential flags.

Version

npx email-sdk version
npx email-sdk --version
npx email-sdk -v
npx email-sdk version --json

version reads the installed @opencoredev/email-sdk package metadata, so it reports the SDK and CLI version from the package currently on your machine. The docs version picker uses the same package version from this repository.

Flags

Flag	Adapter	Notes
`--adapter`	all	Adapter routing name.
`--provider`	all	Alias for `--adapter`.
`--from`	all	Sender address.
`--to`	all	Recipient address. Comma-separated values are allowed.
`--subject`	all	Message subject.
`--text`	all	Plain text body.
`--html`	all	HTML body.
`--cc`	send	Comma-separated CC addresses.
`--bcc`	send	Comma-separated BCC addresses.
`--reply-to`	send	Comma-separated reply-to addresses.
`--header`	send	Header in `Name: value` format. Repeatable.
`--tag`	send	Tag in `name=value` format. Repeatable.
`--metadata`	send	Metadata in `key=value` format. Repeatable.
`--attachment`	send	Local file path, optionally `path:content/type`.
`--message`	send	Read an `EmailMessage` JSON payload from a file.
`--dry-run`	all	Validate the message and adapter field support without sending.
`--json`	version, adapters	Print output as JSON.
`--api-key`	many	Overrides the adapter API key variable.
`--api-token`	Cloudflare	Overrides `CLOUDFLARE_API_TOKEN`.
`--account-id`	Cloudflare	Overrides `CLOUDFLARE_ACCOUNT_ID`.
`--base-url`	Cloudflare	Overrides `CLOUDFLARE_BASE_URL`.
`--server-token`	Postmark	Overrides `POSTMARK_SERVER_TOKEN`.
`--message-stream`	Postmark	Optional message stream.
`--access-key-id`	AWS SES	Overrides `AWS_ACCESS_KEY_ID`.
`--secret-access-key`	AWS SES	Overrides `AWS_SECRET_ACCESS_KEY`.
`--region`	AWS SES	Overrides `AWS_REGION`.
`--session-token`	AWS SES	Overrides `AWS_SESSION_TOKEN`.
`--configuration-set`	AWS SES	Overrides `AWS_SES_CONFIGURATION_SET`.
`--domain`	Mailgun	Overrides `MAILGUN_DOMAIN`.
`--transactional-id`	Loops	Overrides `LOOPS_TRANSACTIONAL_ID`.
`--project-id`	Scaleway	Overrides `SCALEWAY_PROJECT_ID`.
`--secret-key`	Scaleway	Overrides `SCALEWAY_SECRET_KEY`.
`--token`	ZeptoMail	Overrides `ZEPTOMAIL_TOKEN`.
`--host`	SMTP	Overrides `SMTP_HOST`.
`--port`	SMTP	Overrides `SMTP_PORT`.
`--secure`	SMTP	Set to `true` for secure SMTP.
`--require-tls`	SMTP	Require STARTTLS.
`--allow-insecure-auth`	SMTP	Allow SMTP AUTH without TLS.
`--user`	SMTP	Overrides `SMTP_USER`.
`--pass`	SMTP	Overrides `SMTP_PASS`.

The CLI prints the normalized adapter response as JSON.