Postmark - Nitrosend

Use your Postmark account as the sending provider for Nitrosend campaigns, flows, and transactional email. See Email providers for how BYO sending works, plan requirements, and status semantics.

What you need

Your Postmark server token (from the server's API Tokens tab).
Your Postmark account token (from Account → API Tokens).

Both are required: Nitrosend validates the account token against Postmark's domains API and the server token against the server API when it tests the connection.

Connect from the dashboard

Go to Integrations in Nitrosend.
Choose Postmark.
Enter the server token and account token, then save. Nitrosend tests the connection as part of saving a new integration.

Connect via MCP

The tool's generic credential arguments map to Postmark's two tokens:

{
  "operation": "configure",
  "provider": "postmark",
  "api_key": "<POSTMARK_SERVER_TOKEN>",
  "api_secret": "<POSTMARK_ACCOUNT_TOKEN>"
}

Warning

The MCP call stores the tokens without testing them. {"operation": "status"} reports stored configuration only — to actually test the credentials, run Test connection from the Postmark integration page in the dashboard, or call POST /v1/my/integrations/{id}/test via the REST API.

Making it the active provider

If this is your first BYO provider, it becomes the brand's active email provider automatically. If you already had another provider connected, open the integration's page and choose Set as primary to switch sending to it.

Sending domains

After connecting, add your sending domain from Domains (or nitro_manage_domains). The DNS records returned come from Postmark's domain verification.

Troubleshooting

"Postmark account token is invalid" — the account-level token was rejected; copy it from Account → API Tokens (not a server token).
"Postmark server token is invalid" — the server token was rejected; copy it from the specific server's API Tokens tab.
Rotated a token? Re-entering credentials resets this integration's verified domains to pending — re-verify them from Domains.