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.