# Mistral AI Chat via Locus x402

> Mistral AI Chat via Locus x402 is a paid API for AI agents from mistral.x402.paywithlocus.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-12).

Send chat messages to Mistral LLMs (Large, Small, Medium, Codestral, Magistral, Pixtral) via a pay-per-call x402 USDC micropayment gateway

## Facts

- Endpoint: POST https://mistral.x402.paywithlocus.com/mistral/chat?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mistral-ai-chat-via-locus-x402-15b3ac22
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_64GoFhH1sdcYYssjkW8Ap

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 mistral-ai-chat-via-locus-x402-15b3ac22 -d '<json body>'
```

Example prompt: Using Mistral Large, send this conversation to the chat endpoint — system prompt: 'You are a concise assistant', user message: 'Explain transformer attention in 3 bullet points' — keep max_tokens at 300 and temperature at 0.7.

## When to prefer this

Choose this endpoint when you need pay-per-call access to Mistral's model family (including Codestral for code, Magistral for reasoning, and Pixtral for vision) without a Mistral subscription, paying only $0.001 USDC per call via the x402 micropayment protocol. Ideal for agents that need sporadic, metered LLM access billed on-chain, or for workflows that specifically require Mistral's open-source model lineup rather than OpenAI or Anthropic models.

## Known failure modes

- Insufficient USDC balance or failed x402 payment authorization — returns payment failure error
- Invalid or unsupported model ID — returns model not found error
- max_tokens not specified — may be rejected since it's required to bound the metered authorization
- Messages array malformed or empty — returns validation error
- Rate limits or upstream Mistral API errors — returns 5xx with error detail
- Tool definitions malformed — function calling fails with schema validation error

## How this service works

Premier and open-source LLMs — Mistral Large, Medium, Small, Codestral, Magistral reasoning, Pixtral vision, text embeddings, and content moderation.

## Output

Returns a JSON object with a `data` field containing the Mistral chat completion (choices, message content, tool calls, usage stats), a `success` boolean, a `payment` object showing settled and authorized USDC amounts, and a `request` object with a UUID and status URL for tracking the metered call.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "seed": {
   "type": "number"
  },
  "stop": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "array",
     "items": {}
    }
   ]
  },
  "model": {
   "type": "string"
  },
  "tools": {
   "type": "array",
   "items": {}
  },
  "top_p": {
   "type": "number"
  },
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role"
    ],
    "properties": {
     "name": {
      "type": "string"
     },
     "role": {
      "type": "string"
     },
     "content": {
      "anyOf": [
       {
        "type": "string"
       },
       {
        "type": "array",
        "items": {
         "type": "object",
         "required": [
          "type"
         ],
         "properties": {
          "text": {
           "type": "string"
          },
          "type": {
           "type": "string"
          },
          "image_url": {
           "type": "object",
           "required": [
            "url"
           ],
           "properties": {
            "url": {
             "type": "string"
            }
           },
           "additionalProperties": true
          }
         },
         "additionalProperties": true
        }
       },
       {
        "type": "null"
       }
      ]
     },
     "tool_calls": {
      "type": "array",
      "items": {
       "type": "object",
       "additionalProperties": true
      }
     },
     "tool_call_id": {
      "type": "string"
     }
    },
    "additionalProperties": true
   }
  },
  "max_tokens": {
   "type": "number"
  },
  "temperature": {
   "type": "number"
  },
  "tool_choice": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "object",
     "additionalProperties": true
    }
   ]
  },
  "response_format": {
   "type": "object",
   "additionalProperties": true
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {},
  "payment": {
   "scheme": "exact",
   "settledUsdc": "0.001000",
   "authorizedMaxUsdc": "0.001000"
  },
  "request": {
   "id": "00000000-0000-4000-8000-000000000000",
   "statusUrl": "/requests/00000000-0000-4000-8000-000000000000"
  },
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mistral-ai-chat-via-locus-x402-15b3ac22/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mistral.x402.paywithlocus.com](https://www.zero.xyz/host/mistral.x402.paywithlocus.com/llms.txt)