# x402donghang Claude Sonnet 4.6 Chat API

> x402donghang Claude Sonnet 4.6 Chat API is a paid API for AI agents from x402donghang.duckdns.org, paid per call via x402, $0.02/call, status down (last checked 2026-09-15).

Pay-per-call OpenAI-compatible chat completions endpoint powered by Claude Sonnet 4.6, accessible via x402 micropayment protocol at $0.02 USDC per call.

## Facts

- Endpoint: POST https://x402donghang.duckdns.org/x402/v1/models/claude-sonnet-4.6/chat/completions
- Price: $0.02/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402donghang-claude-sonnet-4-6-chat-api-23c04e41
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_eOuOJGkFUMMjyCTOfZUsP

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 x402donghang-claude-sonnet-4-6-chat-api-23c04e41 -d '<json body>'
```

Example prompt: Ask Claude Sonnet 4.6 via x402 to explain the difference between proof-of-work and proof-of-stake in 3 sentences — pay $0.02 USDC from my Base wallet.

## When to prefer this

Choose this endpoint when you need Claude Sonnet 4.6 chat completions on a pay-per-call basis without an Anthropic subscription, especially in crypto-native or x402-enabled agent pipelines where USDC micropayments on Base or Solana are the preferred payment mechanism. Prefer it over the direct Anthropic API when minimizing upfront commitment or when building agents that self-fund via crypto wallets. Avoid it for high-volume workloads where per-call cost accumulates significantly vs. a subscription plan.

## Known failure modes

- Payment not received or insufficient USDC balance — HTTP 402 returned requiring payment
- Invalid model name (must be exactly 'claude-sonnet-4.6') — returns 400 or model not found error
- Malformed messages array missing required 'role' or 'content' fields — returns validation error
- max_tokens set too high for the model context — truncation or error response
- Network timeout on the duckdns.org dynamic host — connection refused or DNS failure
- Rate limiting or server overload on self-hosted infrastructure — 429 or 503 response

## How this service works

Fresh crypto narrative research with market context and verifiable source URLs. Free BTC sample; custom radar $0.02/call via x402 USDC.

## Output

Returns an OpenAI-compatible chat.completion JSON object containing the assistant's reply message, the model name ('claude-sonnet-4.6'), a unique completion ID, and a finish_reason field. The response mirrors the standard /v1/chat/completions response shape, making it drop-in compatible with OpenAI SDK clients.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "type": "string",
   "description": "Use \"claude-sonnet-4.6\""
  },
  "stream": {
   "type": "boolean"
  },
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role",
     "content"
    ],
    "properties": {
     "role": {
      "type": "string"
     },
     "content": {
      "type": "string"
     }
    }
   }
  },
  "max_tokens": {
   "type": "number"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "id": "chatcmpl-x402",
  "model": "claude-sonnet-4.6",
  "object": "chat.completion",
  "choices": [
   {
    "index": 0,
    "message": {
     "role": "assistant",
     "content": "Hello!"
    },
    "finish_reason": "stop"
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402donghang-claude-sonnet-4-6-chat-api-23c04e41/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402donghang.duckdns.org](https://www.zero.xyz/host/x402donghang.duckdns.org/llms.txt)