# X402-NVIDIA GPT-OSS-20B NIM API

> X402-NVIDIA GPT-OSS-20B NIM API is a paid API for AI agents from x402-nvidia.vercel.app, paid per call via x402, $0.135323/call, status unknown (last checked 2026-09-15).

Runs inference on the NVIDIA NIM GPT-OSS-20B model via x402 micropayments, returning chat completion responses.

## Facts

- Endpoint: POST https://x402-nvidia.vercel.app/api/gpt-oss-20b
- Price: $0.135323/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-nvidia-gpt-oss-20b-nim-api-709d79a8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_oytRi_0EeTUoAQsG9hBZH

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 x402-nvidia-gpt-oss-20b-nim-api-709d79a8 -d '<json body>'
```

Example prompt: Use the NVIDIA NIM GPT-OSS-20B model to answer this question: 'What are the key differences between transformer and recurrent neural network architectures?' and pay via x402 micropayment.

## When to prefer this

Choose this endpoint when you need pay-per-call inference on the GPT-OSS-20B open-source model without managing API keys or subscriptions, especially when using x402 USDC micropayments for autonomous agent billing at $0.135 per call.

## Known failure modes

- Insufficient USDC balance or failed x402 micropayment results in 402 Payment Required
- Malformed request body returns 400 Bad Request
- Model overload or NVIDIA NIM backend unavailable returns 503
- Empty or missing messages input may return empty or error response
- Rate limiting may apply if too many calls are made in rapid succession

## How this service works

Access 48+ NVIDIA NIM AI models via x402 micropayments. Chat completions, vision, safety, translation, and more.

## Output

A chat completion object containing an array of choices, each with an assistant message including role and generated text content.

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "example": {
  "choices": [
   {
    "message": {
     "role": "assistant",
     "content": "Hello!"
    }
   }
  ]
 },
 "properties": {
  "choices": {
   "type": "array",
   "description": "Model responses"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-nvidia-gpt-oss-20b-nim-api-709d79a8/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-nvidia.vercel.app](https://www.zero.xyz/host/x402-nvidia.vercel.app/llms.txt)