# Model Access Gateway – Gemini 2.0 Flash (x402 pay-per-call)

> Model Access Gateway – Gemini 2.0 Flash (x402 pay-per-call) is a paid API for AI agents from modelaccessgateway.com, paid per call via x402, $0.0014/call, status unknown (last checked 2026-10-18).

Runs OpenAI-compatible chat completions against Google's Gemini 2.0 Flash model, billed per call in USDC on Base via x402 — no API key or account required.

## Facts

- Endpoint: POST https://modelaccessgateway.com/llm/gemini-3.6-flash?utm_source=zero.xyz
- Price: $0.0014/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-gemini-2-0-flash-x402-pay-per-call-b254612d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dsUoK_Xq1-87UdMmYLCna

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-gemini-2-0-flash-x402-pay-per-call-b254612d -d '<json body>'
```

Example prompt: Ask Gemini 2.0 Flash to summarize the following paragraph in three bullet points, paying per call with no API key: 'Quantum computing uses quantum bits that can exist in superposition, enabling computations impossible for classical computers.'

## When to prefer this

Choose this endpoint when you need Gemini 2.0 Flash specifically, want OpenAI SDK compatibility without maintaining an API key or account, prefer pay-per-call USDC billing on Base (x402), or are building an autonomous agent that needs to self-fund LLM calls. Prefer it over direct Google AI Studio API when you want no account setup, automatic refunds on failure, and crypto-native payment flow.

## Known failure modes

- Payment failure or insufficient USDC balance — x402 payment rejected, no completion returned but refund issued
- Model unavailable or overloaded — gateway returns 5xx with automatic refund
- Invalid messages array (empty or malformed) — 400 validation error
- max_tokens exceeds 16384 — validation error
- Temperature out of 0–2 range — 400 error
- Network timeout before streaming completes — partial response

## 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 message content, finish reason (stop/length/tool_calls), prompt/completion/total token counts, model identifier, and a unique completion ID. Streaming mode delivers server-sent events instead.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "type": "string",
   "description": "Optional: fixed by the route (google/gemini-3.6-flash)"
  },
  "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": "google/gemini-3.6-flash",
  "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-gemini-2-0-flash-x402-pay-per-call-b254612d/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)