The package is n8n-nodes-email-spam-tester. Its source and releases are on GitHub, and it is published to npm from GitHub Actions with a provenance statement, so anyone can check which commit a version was built from.
Connecting
On a self-hosted n8n, open Settings › Community Nodes, press Install and enter n8n-nodes-email-spam-tester. Then get a key with the form above, create an Email Spam Tester API credential in n8n and paste it in. The key is free and tied to the email address you typed. There is no password and nothing is mailed to you; if you lose the key, ask for another with the same address, and the old ones keep working.
The node
Email Spam Tester has four resources:
- Test Address › Create returns a single-use address that is valid for an hour. Send to it from the node that normally sends your mail (Gmail, SMTP or your ESP's), because half of the checks read what that sender adds. With Check Folder at Email Providers switched on, you also get about 30 test mailboxes at 14 providers and a marker for the subject. The Gmail ones are public test mailboxes: anyone there sees the subject, the sender name and the folder, so confidential email should skip the folder check.
- Report › Get reads the report by its test ID. With Wait for Report on, the node holds until the email has arrived and been checked, for up to 15 minutes, and it can also wait for the AI fix plan, which comes about a minute after the checks. Report › Get Many lists past reports, each with what changed since the previous test of that domain.
- Folder Check › Get gives Inbox, Promotions, Spam or not received for each provider. The table is complete about half an hour after sending.
- Permanent Mailbox creates, lists and closes addresses that do not expire, one per sending domain, and Get Emails reads what has arrived at one of them.
A report comes out as ten fields by default. They are the test ID, the score out of 100 and the classic 0 to 10, subject, sender, a summary, the problems, the warnings, the titles of the fixes and the link. Switch Simplify off to get every check with its evidence. The node also works as a tool for n8n's AI Agent.
The trigger
Email Spam Tester Trigger starts a workflow when a report is ready: either for an email sent to one of your test addresses, or for each email that reaches a permanent mailbox. Subscribe a permanent mailbox to your own newsletter, and every issue arrives in the workflow with its score and problems.
Workflows to start with
- Before a campaign goes out, create a test address, send the template to it with the Send Email node, wait for the report, and if the score is below 70 post the problems to Slack instead of sending.
- A weekly check of a sending domain: a Schedule Trigger, the same three steps, and a row in Google Sheets with the score and the date.
- For each new email in a permanent mailbox that scores below 70, send the fixes to whoever owns the newsletter.
Limits
A key gets 50 tests a day, 3 of them with the folder check, and up to 5 permanent mailboxes taking 300 emails a day each. The limit is per key and shared with Zapier if you use the same key there. Past it, Test Address › Create stops with the reason and when it opens again. Tests on the website do not count.
Data
A test report is public to anyone who has its link, as on the site. Reports on emails to a permanent mailbox open only with your key; the email itself is deleted two days after it arrives and its report after 90 days. The privacy policy covers the keys, and the API reference lists every call the node makes.