Resend Schemas

Public Guardian schemas, exported from @tundraconnect/resend/schemas.

import {
  EmailSchemaObject,
  SendEmailRequestSchemaObject,
  WebhookEventSchemaObject,
} from '@tundraconnect/resend/schemas';

Export	Type	Used for
SendEmailRequestSchemaObject	SendEmailRequestSchema	One email's request body, in wire shape.
TemplateSchemaObject	TemplateSchema	A request's template — id and variables.
AttachmentSchemaObject	AttachmentSchema	One entry of attachments.
TagSchemaObject	TagSchema	One { name, value } tag.
EmailRefSchemaObject	EmailRefSchema	{ id, object? } from send / reschedule / cancel.
SendBatchResponseSchemaObject	SendBatchResponseSchema	{ data: EmailRefSchema[] } from a batch send.
EmailSchemaObject	EmailSchema	A retrieved email with its last_event.
WebhookEventSchemaObject	WebhookEventSchema	A verified webhook event { type, created_at, data }.
ErrorResponseSchemaObject	ErrorResponseSchema	Resend's { statusCode, name, message } error body.
MAX_RECIPIENTS	50	The to ceiling.
SENDER_PATTERN	RegExp	Accepted from shapes.
TAG_PATTERN	RegExp	Accepted tag name/value characters.

SendEmailRequestSchema

The wire shape: to, cc, bcc and reply_to are always arrays. The schema accepts a bare string for any of them and normalizes it first — as a single top-level Guardian.preprocess, since a per-field preprocess is silently skipped inside Guardian.object().

from is checked against SENDER_PATTERN rather than .email() so the display-name form Acme <[email protected]> — the one most senders use — is accepted.

The cross-field rule "one of html / text / template" is not expressible in an object schema; Resend.send and Resend.sendBatch enforce it.

TemplateSchema

Variable values must be strings of at most 2,000 characters or finite numbers within ±2^53−1, and names 1–50 ASCII letters, digits or underscores. Values are checked with an explicit typeof, because Guardian's string guard coerces — a boolean would otherwise go out as "true" instead of failing.

AttachmentSchema

Exactly one of content (base64, not a data: URI) or path (a URL Resend fetches) is required — Resend's invalid_attachment rule, checked locally.

EmailSchema

Mirrors GET /emails/{id}. Fields Resend documents as null when unset (html, text, cc, bcc, reply_to, scheduled_at, message_id, tags) are nullable. last_event is an open string and unknown keys pass through, so additive vendor changes never break retrieval.

WebhookEventSchema

data is an open record: its shape depends on type (email.* events carry email_id, to, subject, ...; domain.* and contact.* events carry their resource), and Resend adds event types over time.