# httpay.xyz API Gateway: Anthropic Claude API

> httpay.xyz API Gateway: Anthropic Claude API is a paid API for AI agents from httpay.xyz, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-13).

Proxies requests to the Anthropic Claude messages API, billing per call via x402 micropayments instead of requiring an Anthropic API key

## Facts

- Endpoint: POST https://httpay.xyz/api/gateway/anthropic/v1/messages
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/httpay-xyz-c3324bbc
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_aayfI1vkjASe9Dc29cyCv

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 httpay-xyz-c3324bbc -d '<json body>'
```

Example prompt: Send a message to Claude claude-3-5-sonnet-20241022 asking it to summarize the following paragraph in three bullet points: 'Artificial intelligence has rapidly transformed industries ranging from healthcare to finance, enabling automation of complex tasks and generating insights from massive datasets that would be impossible for humans to process manually.'

## When to prefer this

Choose this endpoint when you need to call Anthropic Claude without provisioning your own Anthropic API key, want pay-per-call billing via x402 USDC micropayments (e.g. $0.005/call), or are building an agent pipeline that needs Claude access with minimal setup. Prefer this over direct Anthropic API when you want to avoid subscription commitments or when x402 payment rails are already in use.

## Known failure modes

- Payment not provided or insufficient — 402 Payment Required with x402 challenge
- Invalid or malformed messages array — 400 Bad Request
- Unsupported model name — 400 or 404 from upstream Anthropic
- Anthropic upstream outage or rate limit — 502 or 503 from gateway
- Request body missing required fields like 'model' or 'messages' — 422 Unprocessable Entity

## How this service works

API Gateway: Anthropic Claude API

## Output

Returns the standard Anthropic Messages API response object, including the assistant's generated content blocks, model name used, stop reason, and token usage counts for input and output — identical to calling Anthropic directly but billed via x402 USDC micropayment.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/httpay-xyz-c3324bbc/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from httpay.xyz](https://www.zero.xyz/host/httpay.xyz/llms.txt)