# GEDX402 Gemma 3 12B Instruct LLM

> GEDX402 Gemma 3 12B Instruct LLM is a paid API for AI agents from chat.gedx402.com, paid per call via x402, $0.035/call, status unknown (last checked 2026-09-15).

Runs inference on Google's Gemma 3 12B Instruct model via Cloudflare Workers AI, payable per-call with USDC on multiple chains — no API key required.

## Facts

- Endpoint: GET https://chat.gedx402.com/v1/llm/gemma-3-12b-it
- Price: $0.035/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/gedx402-gemma-3-12b-instruct-llm-13fea0e6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8jWV09o39tNdmHYrx_jsL

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-gemma-3-12b-instruct-llm-13fea0e6
```

Example prompt: Using the Gemma 3 12B instruct model, reply to this conversation: system says 'You are a helpful assistant', and the user asks 'What are three tips for better sleep?' — limit the response to 300 tokens.

## When to prefer this

Choose this endpoint when you need to run inference on Google's Gemma 3 12B Instruct model without registering for an API key, especially in autonomous agent workflows where per-call USDC micropayments via x402 are preferred over subscription billing. Ideal for agents operating on Base, Polygon, Arbitrum, World, or Solana that want open-weight model inference with no account management overhead.

## Known failure modes

- Payment not received or insufficient USDC balance — request rejected with 402 Payment Required
- Unsupported chain used for payment — transaction not recognized
- max_tokens exceeds 4096 — validation error returned
- Malformed messages array (missing role or content) — schema validation failure
- Model overloaded on Cloudflare Workers AI — timeout or 503 error
- Invalid role value in messages (not system/user/assistant) — rejected by schema

## 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 identifier '@cf/google/gemma-3-12b-it' and a 'response' string with the assistant's generated text reply, up to the specified max_tokens limit.

## 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/google/gemma-3-12b-it",
  "response": "Hello!"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/gedx402-gemma-3-12b-instruct-llm-13fea0e6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chat.gedx402.com](https://www.zero.xyz/host/chat.gedx402.com/llms.txt)