# x402donghang Qwen-3.8-Max Chat Completions

> x402donghang Qwen-3.8-Max Chat Completions is a paid API for AI agents from x402donghang.duckdns.org, paid per call via x402, $0.012/call, status down (last checked 2026-09-15).

Provides OpenAI-compatible chat completions using the Qwen-3.8-Max model, payable per-call in USDC via x402 with no signup required.

## Facts

- Endpoint: POST https://x402donghang.duckdns.org/x402/v1/models/qwen-3.8-max/chat/completions
- Price: $0.012/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402donghang-qwen-3-8-max-chat-completions-8269e3b8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_k6xoiURVyAN3FcNINuesQ

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-qwen-3-8-max-chat-completions-8269e3b8 -d '<json body>'
```

Example prompt: Ask the Qwen-3.8-Max model to write a concise product description for a new ergonomic office chair, keeping it under 150 words and suitable for an e-commerce listing.

## When to prefer this

Choose this endpoint when you need Qwen-3.8-Max specifically, want a pay-per-call model with no monthly subscription, need OpenAI-compatible API shape for drop-in compatibility, or are building an agent that uses USDC micropayments via x402 for LLM inference.

## Known failure modes

- 402 Payment Required if USDC payment via x402 is missing or insufficient
- Invalid model name returns error — must use exactly 'qwen-3.8-max'
- Malformed messages array (missing role or content) causes a 400 error
- Streaming errors if stream:true is set but client doesn't handle SSE
- Service unavailability due to self-hosted duckdns infrastructure downtime

## 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 with an 'id', 'model', 'object', and a 'choices' array containing the assistant's message content and finish reason.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "type": "string",
   "description": "Use \"qwen-3.8-max\""
  },
  "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": "qwen-3.8-max",
  "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-qwen-3-8-max-chat-completions-8269e3b8/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)