GitHub
Email Spam TesterCheck a draft
Check my email for spam problems before I send it.
Here is your test address. It takes one email and lasts an hour.
Claude
Test your email before it goes out, from a Claude chat
Claude gets a test address, you send your real draft to it, and a minute later Claude is reading the report and telling you what to change.
42 checks · No key · No account
From prompt to report
This is the order things happen in, whichever client you use.
You
Check my newsletter before I send it.
Claude4 tools connected
Reserve an address
get_test_addressWait for your email to arrive
wait_for_reportRead the message as delivered
get_message_source
Inbox score
0/100
- SPFpass
- DKIMpass
- DMARCpass
- Blocklistspass
- List-Unsubscribewarning
Fix plan
Add a one click List-Unsubscribe header in your sending platform, then test again.
Scripted example.
A draft reads fine to you.
The receiving server reads something else.
Add it to Claude in a minute
The quick way is the button above. To add it by hand, as a custom connector, these are the steps. Connectors are tied to your account, so once covers web and desktop.
https://email-spam-tester.com/mcpIn Claude Code, install the plugin
The plugin brings the connection and a skill that tells Claude how to run a test and read the result.
/plugin marketplace add serg-tanichev/email-spam-tester-mcp
/plugin install email-spam-tester@email-spam-testerWhat to ask
See the folder
Test my newsletter and show which folder it lands in at different providers.
Add these addresses and keep the marker in the subject.
Fix the records
Read this report and write the DNS records I need to publish: [paste the report link]
DMARC needs one TXT record. Here it is, ready to paste.
Where it lives
Four tools arrive with the connection
Claude writes a decent newsletter and has no way of knowing whether it will arrive. I wanted it to find out for itself, so the connector hands it the same report a person gets here: authentication, blocklists, content, the bulk sender rules, and which DNS record to change.
Claude/mcpget_test_addressReserves a one-hour address. With placement switched on, you also get a list of mailboxes at different providers.
wait_for_reportHolds until the checks finish, then returns the scores, the failed and warned checks with their evidence, and the fix plan.
get_reportReads an existing report by its slug, including how far the folder check has got.
get_message_sourceReturns the email as it arrived, headers in wire order, for an hour after delivery.
Questions
Why does it want a real email instead of pasted text?
About half of the checks read what the sending platform adds: the DKIM signature, the path through its servers, the unsubscribe headers. Pasted text has none of those, so the model would be guessing.
What can the server see?
What you send to the test address. The raw message stays for an hour after it arrives and then only the report remains, at a link anyone with the slug can open. Test mail you would be fine showing a colleague, and read the privacy policy for the rest.
Is the score the same as on the website?
Yes. It is the same analysis and the same report page, so a run from a chat can be compared with one from the home page.
Do I need a paid Claude plan?
Claude decides who can add custom connectors, and that can change. If your plan shows Customize, then Connectors, you can add it.
On a Team or Enterprise plan, who adds it?
An owner, under Organization settings, then Connectors.
Can Claude send the email for me?
Only if another connector you use can send mail. Otherwise it gives you the address and you send from your usual platform.