start
give your agents a bank
Nostro gives every AI agent its own EUR account access and virtual card, in your company's name, with a spending mandate you set. Agents drive it over MCP; humans stay in control.
what nostro is
Agents increasingly need to pay for things: an API plan, a dataset, a domain, a flight, a supplier invoice. Today that means pasting a human's corporate card into a prompt, with no limits, no separation between agents and no audit trail.
Nostro replaces that with four primitives:
- One agent, one card, one key. Each agent gets its own virtual card in the company's name and its own API key. Nothing is shared.
- A mandate checked before the money moves. Per-payment cap, daily and monthly limits, allowed merchant categories (MCC), blocked merchants.
- Human approval above a threshold. Larger spends wait for a person in your company to approve or reject them.
- A complete audit log. Every decision, allowed or not, is recorded with its reason.
how a payment flows
pay over MCP or REST with its nst_ key.The monthly budget is enforced twice: by the mandate engine, and as a spending limit set on the card itself. Even a bug on our side cannot let a card spend beyond its month.
two profiles, one endpoint
Everything goes through https://mcp.nostro.ag/mcp (MCP, Streamable HTTP) or the REST API on https://mcp.nostro.ag. The key you send decides what you can do:
| key | who holds it | what it can do |
|---|---|---|
nst_… | one agent | Read its own wallet, pay, send transfers if allowed, read its own activity and requests. 5 tools. |
nsa_… | a human admin of the workspace | Create agents, set mandates, freeze or revoke, approve requests, fund the sandbox, read the audit log. 12 tools. |
what works today
| capability | sandbox (now) | live (later) |
|---|---|---|
| EUR balance | 10 000 EUR of fake money per workspace | Real EUR account via a licensed EU partner |
| Virtual cards | Simulated, masked numbers, monthly limit enforced | Real cards in the company's name |
| Card payments | Simulated authorization and debit on the virtual ledger | Real merchant payments |
| SEPA transfers | Simulated | Real SEPA |
| Mandates, approvals, audit | Real, same engine as live | Same |
| Company onboarding (KYB) | None needed | Required |