# Model Access Gateway – Llama 3.3 70B Chat Completions (x402, USDC)

> Model Access Gateway – Llama 3.3 70B Chat Completions (x402, USDC) is a paid API for AI agents from modelaccessgateway.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-18).

Runs OpenAI-compatible chat completions using Meta's Llama 3.3 70B model, paid per-call in USDC via x402 with no API key or account required.

## Facts

- Endpoint: POST https://modelaccessgateway.com/llm/llama-3.3-70b?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/model-access-gateway-llama-3-3-70b-chat-completions-x402-usdc-443fca1c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XuOvlnzJ4iw27APHuSV0h

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 model-access-gateway-llama-3-3-70b-chat-completions-x402-usdc-443fca1c -d '<json body>'
```

Example prompt: Ask Llama 3.3 70B to write a concise summary of this customer feedback — pay per call in USDC so I don't need an API key: 'The product arrived late and the packaging was damaged, but the item itself works perfectly.'

## When to prefer this

Choose this endpoint when you need Llama 3.3 70B specifically, want a fully OpenAI-compatible interface, need to avoid account registration or API key management, and are comfortable paying per-call in USDC on Base via x402. Ideal for autonomous agents that need permissionless, pay-as-you-go LLM inference with automatic refunds on failure. Prefer this over subscription-based APIs for sporadic or unpredictable workloads, or when building crypto-native agent workflows.

## Known failure modes

- Payment failure or insufficient USDC balance — x402 payment rejected, no inference run and automatic refund issued
- Model inference error — upstream model fails, automatic refund triggered
- Invalid messages array (empty or malformed) — 400 validation error
- max_tokens exceeds 16384 — rejected with schema validation error
- Network timeout during streaming — partial SSE stream with no explicit error frame
- Unsupported response_format schema — model may ignore or return unstructured output

## How this service works

LLM inference API: OpenAI-compatible chat completions for 136 AI models (Claude, GPT, Gemini, Grok, DeepSeek, Qwen, Kimi, GLM), paid per call in USDC on Base with x402. No account, no API key, automatic refund if the model fails.

## Output

Returns an OpenAI-compatible chat.completion JSON object containing the assistant's generated message, finish reason (e.g. 'stop'), token usage breakdown (prompt, completion, total), model identifier, and a unique completion ID. Streaming mode returns server-sent events incrementally after payment is confirmed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "type": "string",
   "description": "Optional: fixed by the route (meta-llama/llama-3.3-70b)"
  },
  "tools": {
   "type": "array"
  },
  "stream": {
   "type": "boolean",
   "description": "true: server-sent events after payment"
  },
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role"
    ],
    "properties": {
     "role": {
      "enum": [
       "system",
       "user",
       "assistant",
       "tool",
       "developer"
      ],
      "type": "string"
     },
     "content": {
      "type": [
       "string",
       "array",
       "null"
      ]
     }
    }
   },
   "minItems": 1
  },
  "max_tokens": {
   "type": "integer",
   "maximum": 16384,
   "minimum": 1,
   "description": "Optional, default 4096"
  },
  "temperature": {
   "type": "number",
   "maximum": 2,
   "minimum": 0
  },
  "response_format": {
   "type": "object"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "id": "chatcmpl-7f3c2a91",
  "model": "meta-llama/llama-3.3-70b",
  "usage": {
   "total_tokens": 10,
   "prompt_tokens": 9,
   "completion_tokens": 1
  },
  "object": "chat.completion",
  "choices": [
   {
    "index": 0,
    "message": {
     "role": "assistant",
     "content": "OK"
    },
    "finish_reason": "stop"
   }
  ],
  "created": 1791979200
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/model-access-gateway-llama-3-3-70b-chat-completions-x402-usdc-443fca1c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from modelaccessgateway.com](https://www.zero.xyz/host/modelaccessgateway.com/llms.txt)