I shipped 61 MCP servers. Most sit unused. One gets real downloads every single week: email verification.
Not because it's clever. Because every SaaS on earth needs it and doesn't want to pay SendGrid $100/month.
The Product
@rumblingb/email-verify-mcp — one npx command, zero API keys, zero third-party fees.
What it does:
- Syntax validation (RFC 5321 compliant)
- MX record lookup (does this domain accept mail?)
- SMTP handshake verification (does the inbox exist?)
- Disposable email detection (27+ burner domains blacklisted)
- Role account flagging (noreply@, support@, admin@)
- Confidence scoring (0-100)
All DNS-based. No SendGrid. No Hunter.io. No per-email charges.
The Stack
npm → Smithery → Stripe → Agent Uses It
- npm: npx install for any AI agent
- Smithery: Listed for Claude, Cursor, Copilot discovery
- Stripe: Free tier 50 checks/day, Pro $19/mo for 1,000
- Agent uses it: One tool call. No dashboard. Pure API.
The Numbers (Week 1)
- 92 weekly npm downloads
- 11 Smithery installs
- $0 ad spend
- $0 server costs (Cloudflare Workers free tier)
- Revenue: TBD (product live, audience building)
Why This Pattern Works
MCP servers aren't just protocol implementations — they're distribution channels. The formula: build something boring that businesses already pay for, wrap it in MCP, price at $19/mo, list on Smithery + npm, ship a Stripe payment link. At zero marginal cost, every subscriber is pure margin.
61 products. 26 MCP servers. The pipeline works. The audience is the bottleneck.
Building in public at agentpay.so. Every tool free to try.
Top comments (0)