# x402engine Llama 4 Maverick LLM

> x402engine Llama 4 Maverick LLM is a paid API for AI agents from x402engine.app, paid per call via x402, $0.002801/call, status unknown (last checked 2026-10-12).

Run inference on Meta's Llama 4 Maverick model via a pay-per-call HTTP 402 micropayment API, returning OpenAI-compatible chat completions

## Facts

- Endpoint: POST https://x402engine.app/api/llm/llama-4-maverick?utm_source=zero.xyz
- Price: $0.002801/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402engine-llama-4-maverick-llm-a41b7841
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2WgLrnbpiagzT6GDerHAm

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 x402engine-llama-4-maverick-llm-a41b7841 -d '<json body>'
```

Example prompt: Ask Llama 4 Maverick: 'Explain the differences between supervised and reinforcement learning in three paragraphs' — pay per call with USDC and stream the response back to me.

## When to prefer this

Choose this endpoint when you need Meta Llama 4 Maverick specifically (strong multimodal and tool-calling capabilities) and want pay-per-call pricing with no subscription or API key — ideal for agents that need to control cost at the individual call level using crypto micropayments (USDC on Base, USDm on MegaETH, or USDC on Solana). Prefer over hosted inference APIs when you want OpenAI-compatible output format without vendor lock-in.

## Known failure modes

- Payment not settled — HTTP 402 returned if USDC/USDm micropayment is not attached or insufficient
- Invalid messages format — missing required 'role' or both 'content' and 'tool_calls' fields causes a 422 validation error
- Unsupported parameter for model — some sampling params (seed, logprobs, min_p) may not be supported by Maverick; check /docs/llm-capabilities.md
- Context length exceeded — very long message arrays may exceed model context window and return an error
- Streaming timeout — SSE stream may drop if network latency is too high after payment settlement

## How this service works

125 production APIs behind HTTP 402 micropayments. 87 LLMs, Kling V3 and Hailuo video generation, image generation, code execution, travel search, web scraping, TTS, and transaction simulation. Pay with USDC on Base, USDm on MegaETH, or USDC on Solana.

## Output

An OpenAI-compatible JSON response containing a choices array with the assistant's message (text content or tool_calls), the finish_reason (stop, tool_calls, length, etc.), and the model name. When streaming is enabled, returns OpenAI-compatible server-sent events (SSE) chunks in real time.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "bodyType",
    "body",
    "method"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "messages"
     ],
     "properties": {
      "seed": {
       "type": "integer",
       "description": "Model-supported seed; see /docs/llm-capabilities.md."
      },
      "stop": {
       "oneOf": [
        {
         "type": "string"
        },
        {
         "type": "array",
         "items": {
          "type": "string"
         },
         "maxItems": 4
        }
       ],
       "description": "Model-supported stop; see /docs/llm-capabilities.md."
      },
      "min_p": {
       "type": "number",
       "description": "Model-supported min_p; see /docs/llm-capabilities.md."
      },
      "tools": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "function"
        ],
        "properties": {
         "type": {
          "enum": [
           "function"
          ],
          "type": "string"
         },
         "function": {
          "type": "object",
          "properties": {
           "name": {
            "type": "string"
           },
           "strict": {
            "type": "boolean"
           },
           "parameters": {
            "type": "object"
           },
           "description": {
            "type": "string"
           }
          }
         }
        }
       },
       "description": "Client-executed function definitions; return results using role=tool and tool_call_id."
      },
      "top_k": {
       "type": "integer",
       "description": "Model-supported top_k; see /docs/llm-capabilities.md."
      },
      "top_p": {
       "type": "number",
       "description": "Model-supported top_p; see /docs/llm-capabilities.md."
      },
      "stream": {
       "type": "boolean",
       "description": "Return live OpenAI-compatible SSE after payment settlement."
      },
      "logprobs": {
       "type": "boolean",
       "description": "Model-supported logprobs; see /docs/llm-capabilities.md."
      },
      "messages": {
       "type": "array",
       "items": {
        "type": "object",
        "anyOf": [
         {
          "required": [
           "content"
          ]
         },
         {
          "required": [
           "tool_calls"
          ]
    
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "model": "meta-llama/llama-4-maverick",
  "choices": [
   {
    "index": 0,
    "message": {
     "role": "assistant",
     "content": "Hello!"
    },
    "finish_reason": "stop"
   }
  ],
  "content": "Hello!"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402engine-llama-4-maverick-llm-a41b7841/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402engine.app](https://www.zero.xyz/host/x402engine.app/llms.txt)