Inbox Check — Email Deliverability Test MCP Server

Email inbox placement tests across Gmail, Outlook, Yahoo, Mail.ru, Yandex (SPF/DKIM/DMARC). The inbox check — email deliverability test mcp server wraps that behind the Model Context Protocol, so an assistant can use it through 2 defined tools rather than through you.

What it actually does

Plug real inbox-placement testing into Claude Desktop, Cursor, Windsurf, Cline, or any other MCP-compatible AI client. The server wraps the Inbox Check REST API and exposes 5 tools your agent can call directly — create a test, send your email to the returned seed addresses, and read back per-provider placement (Inbox / Spam / Promotions / Updates), authentication results (SPF, DKIM, DMARC), headers, and screenshots.

• 9 real provider mailboxes — — Gmail, Outlook, Yahoo, iCloud, AOL, GMX,
• Authentication verification — — SPF, DKIM, DMARC alignment reported
• Folder detection — — Inbox, Spam, Promotions, Updates, Social,
• Screenshots — — rendered inbox/spam list view for Gmail, Outlook
• No flaky scraping — — the service runs its own seed mailboxes; your
• Built for AI agents — — strict JSON schema via Zod, deterministic

Adding it to your client

Being a remote server, there is no local install. You register the endpoint with your client, authorise it once, and the tools appear.

Its toolset

Everything the assistant can do here goes through one of these:

• Cursor — The Cursor tool exposed by this server
• Windsurf — The Windsurf tool exposed by this server

Configuration

You will need 2 environment variables: INBOX_CHECK_API_KEY, INBOX_CHECK_BASE_URL. The server will not start without them, which is usually why the tools fail to appear on a first run. Keep credentials in your client's env block or a secrets manager rather than in a file you might commit.

Caveats

• Your data travels to the provider's service, so the usual questions apply about what you send and what they retain.
• Missing credentials fail quietly in some clients — if no tools show up, check the environment block first.
• MCP clients confirm each tool call by default. Leave that on until you have watched what the inbox check — email deliverability test mcp server does with a few real requests.

When to reach for it

This sits in the team communication group, where several servers overlap in what they claim to do but differ sharply once you actually set them up. Inbox Check — Email Deliverability Test's toolset — Cursor, Windsurf — is a fair guide to whether it matches your workflow. It is maintained by live-direct-marketing; worth a glance at recent repository activity before you build anything load-bearing on it.

We check each listing at SyncDev against the project's documentation before it goes live — if something here drifts out of date, it is a bug worth reporting.