# Agent402 UK Bank Account Modulus Validator

> Agent402 UK Bank Account Modulus Validator is a paid API for AI agents from agent402.co.uk, paid per call via x402, $0.001/call, status down (last checked 2026-09-15).

Validates UK sort code and account number pairs using Vocalink modulus check algorithms (MOD10/11/DBLAL with exceptions) — checksum only, not bank name or account existence

## Facts

- Endpoint: POST https://agent402.co.uk/v1/validate/uk-bank
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent402-uk-bank-account-modulus-validator-b486f42d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_yEgW7OR9WT_8uaxJCzIjp

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability agent402-uk-bank-account-modulus-validator-b486f42d -d '<json body>'
```

Example prompt: Can you run a Vocalink modulus check on UK sort code 20-00-00 and account number 55779911 to see if the combination passes the checksum?

## When to prefer this

Choose this endpoint when you need a fast, cheap ($0.001) structural checksum validation of UK sort code and account number pairs using the official Vocalink modulus algorithm (MOD10/MOD11/DBLAL with exceptions) — ideal as a pre-flight check before initiating payments or onboarding bank details. Prefer over manual regex checks that miss exception tables. Not suitable if you need to verify account existence, retrieve bank name, or validate IBANs — use a bank lookup or IBAN validation service for those needs.

## Known failure modes

- Invalid or missing sort_code format — should be 6 digits (dashes accepted)
- Account number outside 6–10 digit range causes validation rejection
- Sort code not found in Vocalink modulus weight table — returned as invalid
- Network or service error returning non-200 response
- Payment failure (x402) if USDC balance insufficient

## How this service works

Don't burn tokens on deterministic work. Go/no-go jobs first: payout preflight, text firewall (PII/secrets), budget check — then rails, calendars, finmath. x402 USDC on Base. UK + global. agent402.co.uk — not agent402.tools. $0.001–$0.002 USDC on Base. No API keys.

## Output

Returns a JSON object with a boolean 'valid' field indicating whether the sort code and account number pass the Vocalink modulus check, the 'algorithm' used (e.g. 'vocalink-modulus'), the normalised 'sort_code' and 'account_number', and a 'provenance' object with 'depth' set to 'checksum_only' — confirming this is a structural checksum validation, not a live bank lookup.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "sort_code": {
   "type": "string",
   "description": "6-digit sort code (##-##-## ok)"
  },
  "account_number": {
   "type": "string",
   "description": "Account number (6–10 digits)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "valid": true,
  "algorithm": "vocalink-modulus",
  "sort_code": "200000",
  "provenance": {
   "depth": "checksum_only"
  },
  "account_number": "55779911"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent402-uk-bank-account-modulus-validator-b486f42d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent402.co.uk](https://www.zero.xyz/host/agent402.co.uk/llms.txt)