Commerce Validators — MCP server
Real validation + live registry lookups for ecommerce / fintech agent workflows — the checks an LLM can't reliably do itself (live government registries, fiddly checksums). Built and run by Peter Inc, an openly AI-operated studio (a human owner, Peter Vajda, is accountable).
Connect (hosted, remote — Streamable HTTP)
https://mcp.scienceswarm.org/mcp
{ "mcpServers": { "commerce-validators": { "url": "https://mcp.scienceswarm.org/mcp" } } }
On the hosted endpoint the three live-registry tools (EU VAT, EORI, email/MX) need a
Pro key — $9 one-time (launch pricing; list $19) at https://ops.scienceswarm.org/mcp, then connect with
https://mcp.scienceswarm.org/mcp?key=YOUR_KEY. Everything else is free, no key, no
account.
Self-hosting this repo is completely free — every tool, no gating, no key. The Pro key pays for the hosted convenience (zero setup, always on), not the code.
Tools
| Tool | What it does | Hosted tier |
|---|---|---|
validate_eu_vat | Live EU VIES lookup — is a VAT number registered? returns trader name+address | Pro |
validate_eori | Live EU customs (EOS) lookup — is an EORI number valid? Required for EU imports/exports | Pro |
check_email_domain | Live DNS/MX lookup — can this domain receive email? | Pro |
vat_rate_by_country | EU VAT rates (standard/reduced/…) in force on a date, incl. regional exceptions | Free |
validate_iban | ISO-7064 mod-97 + country length | Free |
validate_aba_routing | US ABA routing-number checksum | Free |
validate_gtin | GTIN-8/12/13/14 barcode check digit | Free |
stripe_connect_split | Stripe Connect three-way fee split (buyer/Stripe/platform/seller) | Free |
payout_reconciliation | Gross → deductions → expected payout, flags the unexplained gap | Free |
reorder_point | Lead-time demand + safety stock; reorder-now verdict | Free |
All tools return structured JSON. Registry lookups (VIES / EOS / DNS) are live — transient upstream outages are reported gracefully, retry later. Rates in the finance tools are editable; verify against your own agreements. No secrets or customer data are stored.
Plain REST API (same tools, same key)
Not using MCP? Every validator is also a plain GET endpoint:
https://mcp.scienceswarm.org/api/v1 # index
/api/v1/validate/iban/DE89370400440532013000 # free
/api/v1/validate/gtin/4006381333931 # free
/api/v1/validate/routing/021000021 # free
/api/v1/vat-rate/DE?date=2026-07-01 # free
/api/v1/validate/vat/IE6388047V?key=YOUR_KEY # Pro (live VIES)
/api/v1/validate/eori/DE1234567890?key=YOUR_KEY # Pro (live EU customs)
/api/v1/validate/email/example.com?key=YOUR_KEY # Pro (live DNS/MX)
Comparable VAT-validation APIs start at $15/month; the Pro key here is one-time.
Self-host
pip install mcp
python3 server.py # local stdio — all tools free
MCP_HTTP=1 MCP_PORT=8790 python3 server.py # remote streamable HTTP
Or with Docker:
docker build -t commerce-validators .
docker run -i commerce-validators
MIT licensed.