Mailtrap

Send through the Mailtrap Email Sending API with full field support and provider-side message inspection.

Capabilities

Repeated headers	Idempotency	Scheduling	Personalized
No	`none`	No	`expanded`

These values come from the adapter's exported capabilities declaration. The field support matrix covers normalized message fields.

The Mailtrap adapter calls the Mailtrap Email Sending API with plain fetch. It supports every common transactional field, and Mailtrap's inspection tooling makes it a natural pick for staging environments.

Mailtrap@opencoredev/email-sdk/mailtrap

Provider docs

Configure

Create a Mailtrap API token with Email Sending permission and verify your sending domain.

lib/email.ts

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

export const email = createEmailClient({
  adapters: [mailtrap({ apiKey: process.env.MAILTRAP_API_KEY! })],
});

Prop

Type

Send

Mailtrap maps cc, bcc, headers, attachments, metadata, and tags, with two limits: at most one tag (its value becomes the Mailtrap category) and at most one replyTo. metadata is sent as custom_variables with values stringified (null becomes "").

const result = await email.send({
  from: "Acme <hello@acme.com>",
  to: "user@example.com",
  cc: "billing@acme.com",
  replyTo: "support@acme.com",
  subject: "Your receipt for order ord_123",
  html: "<p>Thanks for your order. Receipt attached.</p>",
  tags: [{ name: "type", value: "receipt" }],
  metadata: { orderId: "ord_123" },
  attachments: [
    { filename: "receipt.pdf", path: "./receipts/ord_123.pdf" },
  ],
});

console.log(result.id); // first entry of Mailtrap's message_ids

One tag, one reply-to

A second tag or a second replyTo throws an EmailValidationError before any request. Trim to one of each when Mailtrap sits in a fallback route behind a multi-tag adapter.

Verify from the CLI

MAILTRAP_API_KEY="..." npx email-sdk doctor --adapter mailtrap

MAILTRAP_API_KEY="..." npx email-sdk send \
  --adapter mailtrap \
  --from "Acme <hello@acme.com>" \
  --to user@example.com \
  --subject "Mailtrap smoke test" \
  --text "It works" \
  --dry-run

Drop --dry-run for one real smoke send, and confirm the token targets the intended Mailtrap project before pointing production at it.

Capabilities

Configure

Send

Verify from the CLI

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