> ## Documentation Index
> Fetch the complete documentation index at: https://docs.corsair.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Postmark plugin

> Transactional email API for sending single and batch messages, managing templates and streams, and reading delivery statistics.

Use **Postmark** through Corsair: one client, typed API calls.

Postmark sends transactional email. Create a server token under the API Tokens tab of a server and paste it in; it travels in the `X-Postmark-Server-Token` header. The account token covers a different set of account-level routes, which this plugin does not wrap, so one server token is all it needs.

What to know before you send:

* **A send cannot be recalled.** `email.send` and `email.sendBatch` deliver real mail. A server in Sandbox mode accepts sends without delivering them, but that is a server setting rather than a request flag.
* **A 200 batch is not a success.** `email.sendBatch` answers HTTP 200 with one result per message, and each carries its own `ErrorCode`. `0` means sent, and anything else means that message failed while the others may have gone out.
* **The sender must be verified.** `From` needs a confirmed Sender Signature or a verified domain, or the send is rejected with code 300.
* **A body is required.** Supply `TextBody`, `HtmlBody`, or both; the plugin rejects a message with neither before it is sent.
* **Attachments are base64.** Give each one a `Name`, a `Content` and a `ContentType`, and set `ContentID` to reference it as `cid:` from the HTML.
* **Paging is by offset.** List routes take `Count` and `Offset` (100 and 0 when left out) and return `TotalCount`; page while the offset is below it. Note that the bounces route spells its parameters in lowercase, which this plugin maps for you.
* **Stats are limited.** The overview accepts a window no older than a year, and the stats API needs the plan that includes it.
* **Retries.** A 429 is retried three times by Corsair's request layer, which waits for a `Retry-After` when Postmark sends one. A 5xx or a dropped connection is retried only on reads; a send is never replayed.
* **Webhooks.** Postmark posts delivery, bounce and inbound events to a URL you register, but this plugin does not handle inbound deliveries.

**What you get:**

* 19 typed API operations

## Setup

**1. Install**

```bash npm theme={null}
npm install corsair @corsair-dev/postmark better-sqlite3
npm install --save-dev @types/better-sqlite3
```

```bash yarn theme={null}
yarn add corsair @corsair-dev/postmark better-sqlite3
yarn add --dev @types/better-sqlite3
```

```bash pnpm theme={null}
pnpm install corsair @corsair-dev/postmark better-sqlite3
pnpm install --save-dev @types/better-sqlite3
```

```bash bun theme={null}
bun add corsair @corsair-dev/postmark better-sqlite3
bun add --dev @types/better-sqlite3
```

**2. Add the plugin**

```ts corsair.ts theme={null}
import Database from 'better-sqlite3';
import { createCorsair } from 'corsair';
import { postmark } from '@corsair-dev/postmark';

export const corsair = createCorsair({
	plugins: [
		postmark(),
	],
	database: new Database('corsair.db'),
	kek: process.env.CORSAIR_KEK!,
	multiTenancy: true,
	hub: {
		projectApiKey: process.env.CORSAIR_API_KEY!,
		signingSecret: process.env.CORSAIR_SIGNING_SECRET!,
	},
});
```

With `multiTenancy: true`, scope calls with `corsair.withTenant(id)`. See [Quick start](https://docs.corsair.dev/quick-start.md) for KEK + Hub keys, and [Multi-tenancy](https://docs.corsair.dev/concepts/multi-tenancy.md) for account isolation.

**3. Choose authentication**

> [tab] API Key (Recommended)
>
> Store the Postmark API key before the first call: `pnpm corsair setup --plugin=postmark --tenant=acme api_key=<your-key>` (leave out `--tenant` without `multiTenancy`), or pass it as `key` in the plugin options. With Hub, each tenant enters their own key on the connect page. See [API key auth](https://docs.corsair.dev/concepts/api-key).
>
> ```ts theme={null}
> postmark()
> ```
>
> More: [API Key](https://docs.corsair.dev/concepts/api-key)

**4. Connect a tenant**

Mint a connect link and send the tenant to it. Hub hosts the page and delivers the result to your app — see [Connect / OAuth](https://docs.corsair.dev/management/connect).

```ts theme={null}
const { connectUrl } = await corsair.manage.connect.createLink({
	plugin: 'postmark',
	tenantId: 'acme',
});
// redirect the user's browser to connectUrl
```

## Example API calls

**Read this server's settings**

```ts theme={null}
const tenant = corsair.withTenant('acme');
await tenant.postmark.api.server.get({});
```

**Create a welcome template**

```ts theme={null}
const tenant = corsair.withTenant('acme');
await tenant.postmark.api.templates.create({
	Name: 'Welcome Email',
	Alias: 'onboarding-v1',
	Subject: 'Hello, from {{company.name}}',
	HtmlBody: '<html><body>Hello {{name}}</body></html>',
});
```

See the full list on the [API](https://docs.corsair.dev/plugins/postmark/api.md) page.

## What's next

> [card] [API reference](https://docs.corsair.dev/plugins/postmark/api.md)
>
> Every `postmark.api.*` operation with input and output types.

> [card] [Connect / OAuth](https://docs.corsair.dev/management/connect)
>
> createLink, Hub delivery, and tenant connect flows.

> [card] [Use with agents](https://docs.corsair.dev/mcp-adapters/mcp-adapters)
>
> Expose this plugin's operations as MCP tools.


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