Anthropic via Spawnpay

Route Claude Opus, Sonnet, and Haiku through Spawnpay with the same billing pipeline as every other paid tool.

Why route through Spawnpay

Building agents that fall back from local Claude Code → hosted Claude API. Multi-tenant tools that bill per token-equivalent in USDC. A unified receipt log so finance can reconcile across providers.

Endpoint

curl

curl -X POST https://spawnpay.ai/api/proxy \
  -H 'Authorization: Bearer spk_live_…' \
  -H 'X-Provider-Key: $ANTHROPIC_KEY' \
  -H 'Content-Type: application/json' \
  -d '{
  "provider": "anthropic",
  "path": "/v1/messages",
  "method": "POST",
  "body": {
    "model": "claude-haiku-4-5-20251001",
    "max_tokens": 256,
    "messages": [
      {
        "role": "user",
        "content": "hello"
      }
    ]
  }
}'

Node (spawnpay-paywall)

import { proxy } from 'spawnpay-paywall';

const out = await proxy({
  "provider": "anthropic",
  "path": "/v1/messages",
  "method": "POST",
  "body": {
    "model": "claude-haiku-4-5-20251001",
    "max_tokens": 256,
    "messages": [
      {
        "role": "user",
        "content": "hello"
      }
    ]
  },
  "providerKey": process.env.ANTHROPIC_KEY
});

console.log(out.status, out.body);
console.log('charged', out.charged); // txHash + $0.001 USDC receipt

What you get back

The full upstream JSON body, the upstream status code, the upstream response headers, plus a charged field with the USDC receipt (tx hash) when the call succeeded.