security.password-exposure

Check whether a password has appeared in known data breaches, using Have I Been Pwned's Pwned Passwords k-anonymity model — only the first 5 characters of the password's SHA-1 hash are ever sent upstream, so the service never sees the password or the full hash. POST { password } (hashed server-side) OR { sha1 } (the 40-hex SHA-1, for true zero-knowledge — hash it client-side and send only that). Returns breached (boolean), count (how many times it appears in breach corpora), and the sha1Prefix used. Backed by a 900M+ breached-credential corpus an LLM cannot know. For signup/password-policy enforcement and credential-hygiene checks. Absence is not a guarantee of strength.

price

$0.0010 USDC per call

method

POST/api/security/password-exposure

payment

x402 v2 · USDC on Base (EIP-3009) or Solana (SPL transfer)

auth

None. Sign the payment, retry with PAYMENT-SIGNATURE.

tier

Tier 0 — no paid upstream

Parameters

Name	Type	Description
`password`	string	min 1 chars · max 512 chars
`sha1`	string	min 40 chars · max 40 chars

Code samples

cURLbash

# 1. Probe the endpoint with no auth — receive 402 with PaymentRequirements
curl -sS -X POST 'https://2s.io/api/security/password-exposure' \
  -H 'Content-Type: application/json' \
  -d '{"password":"example","sha1":"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"}'

# 2. Sign the EIP-3009 transferWithAuthorization for the advertised price +
#    payTo from the 402 envelope, then retry with PAYMENT-SIGNATURE:
curl -sS -X POST 'https://2s.io/api/security/password-exposure' \
  -H 'Content-Type: application/json' \
  -H 'PAYMENT-SIGNATURE: <base64-json-payload>' \
  -d '{"password":"example","sha1":"xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"}'

# Or just use the canonical runner — it handles the whole loop:
#   EVM_PRIVATE_KEY=0x... node --env-file=.env.local \
#     --experimental-strip-types scripts/x402-pay.ts \
#     'https://2s.io/api/security/password-exposure'

TypeScript / Node — @2sio/sdktypescript

import { TwoS } from '@2sio/sdk'

const client = new TwoS({
  privateKey: process.env.EVM_PRIVATE_KEY as `0x${string}`,
})

const result = await client.security.passwordExposure({
  "password": "example",
  "sha1": "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
})

console.log('endpoint:', result.endpoint)
console.log('cost:', result.costUsd, 'USDC')
console.log('tx:', result.settlement?.txHash)
console.log('data:', result.data)

Python — 2siopython

import os
from twosio import TwoS

client = TwoS(private_key=os.environ["EVM_PRIVATE_KEY"])

result = client.security.password_exposure(password="example", sha1="xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx")

print("endpoint:", result.endpoint)
print("cost:", result.cost_usd, "USDC")
print("tx:", (result.settlement or {}).get("tx_hash"))
print("data:", result.data)

MCP — Claude Desktop / AgentKit / any MCP hostjson

// 1. Add @2sio/mcp to your MCP host config (Claude Desktop example below).
//    EVM_PRIVATE_KEY funds x402 payments per call.

// claude_desktop_config.json
{
  "mcpServers": {
    "2sio": {
      "command": "npx",
      "args": ["-y", "@2sio/mcp"],
      "env": { "EVM_PRIVATE_KEY": "0x..." }
    }
  }
}

// 2. Once the server is running, agents call this tool via standard MCP:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "security.password-exposure",
    "arguments": {
      "password": "example",
      "sha1": "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
    }
  }
}

Response

Field	Type	Description
`ok`	boolean	one of: true
`items`	array
`total`	integer	Total matching rows upstream; null when unknown.
`source`	object

Example response datajson

{
  "ok": true,
  "items": [
    {
      "breached": false,
      "count": 1,
      "sha1Prefix": "example",
      "inputMode": "example",
      "note": "example"
    }
  ],
  "total": 1,
  "source": {
    "provider": "example",
    "url": "example",
    "license": "example"
  }
}

Discovery

/api/directory — full catalog of every endpoint
/openapi.json — OpenAPI 3.1 spec (per-op x-payment-info, x402Payment security)
/.well-known/x402 — machine-readable service descriptor for x402-aware crawlers
/.well-known/mcp/server-card.json — MCP SEP-1649 server card
/llms.txt — plain-text manifest for LLM ingestion

2s.io is x402-native. Every call is paid per-request from a USDC-funded EVM wallet on Base — no signup, no API keys, no monthly fees. Source code: github.com/2s-io/sdk.