# GEDX402 GPT-OSS-120B LLM via x402

> GEDX402 GPT-OSS-120B LLM via x402 is a paid API for AI agents from llm.gedx402.com, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Runs a 120B open-source GPT-class language model inference call, paid per-call in USDC via x402 with no API key required.

## Facts

- Endpoint: GET https://llm.gedx402.com/v1/llm/gpt-oss-120b
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/gedx402-gpt-oss-120b-llm-via-x402-3b97b08a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_yhP1KXB6zpS18ijiehjhl

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 gedx402-gpt-oss-120b-llm-via-x402-3b97b08a
```

Example prompt: Ask the GPT-OSS-120B model this for me — no API key needed, just pay per call in USDC: 'You are a helpful assistant. What are the top three benefits of renewable energy?' Keep the response under 200 tokens.

## When to prefer this

Choose this endpoint when you need a large (120B parameter) open-source GPT-class model with no API key registration, paying strictly per call in USDC via x402. Ideal for agents that need anonymous or wallet-based LLM access, or when avoiding subscription-based API keys. Prefer over smaller models when response quality from a 120B model matters. Good fit for crypto-native pipelines already using x402 for other services.

## Known failure modes

- Payment not received or insufficient USDC balance — returns HTTP 402 requiring payment
- Invalid message schema (missing role or content fields) — returns 4xx validation error
- max_tokens exceeds 4096 — returns 400 bad request
- Model unavailable on Cloudflare Workers AI backend — returns 5xx
- Unsupported payment chain specified — payment rejected at facilitator level

## How this service works

x402 workers ai. pay with usdc on base, polygon, arbitrum, world, or solana. no api keys.

## Output

A JSON object containing the model name ('model': '@cf/openai/gpt-oss-120b') and the generated assistant reply text ('response': '...'). The response is the raw text completion from the 120B model for the provided conversation input.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role",
     "content"
    ],
    "properties": {
     "role": {
      "enum": [
       "system",
       "user",
       "assistant"
      ],
      "type": "string",
      "description": "Speaker role for this turn."
     },
     "content": {
      "type": "string",
      "description": "Message text for this turn."
     }
    }
   },
   "description": "Conversation turns in order (system, user, assistant)."
  },
  "max_tokens": {
   "type": "integer",
   "maximum": 4096,
   "minimum": 1,
   "description": "Maximum tokens to generate in the assistant reply."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "model": "@cf/openai/gpt-oss-120b",
  "response": "Hello!"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/gedx402-gpt-oss-120b-llm-via-x402-3b97b08a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from llm.gedx402.com](https://www.zero.xyz/host/llm.gedx402.com/llms.txt)