X4
MCP Tool · x402 · early usage

LLM Chat: Chat with a language model

LLM Chat: Chat with a language model. OpenAI-compatible /v1/chat/completions interface. Supports 50+ models. Free models (auto, eco, premium) are $0 — paid models (gpt-5.2, claude-opus-5, deepseek-v4-pro, ...) are charged at cost. See /tools/llm_chat/models f…

by x402.freeq.one · discovered, not yet claimed by its owner · updated 2026-08-27

30d calls12
30d payers1
MethodPOST
Outputjson

Mirrored from Coinbase's public x402 Bazaar. The description is the provider's own text and has not been reviewed here; the payment requirements are copied as published.

What it does

LLM Chat: Chat with a language model. OpenAI-compatible /v1/chat/completions interface. Supports 50+ models. Free models (auto, eco, premium) are $0 — paid models (gpt-5.2, claude-opus-5, deepseek-v4-pro, ...) are charged at cost. See /tools/llm_chat/models for the full model list and rates. Pay per call in USDC on Base via x402 — POST https://x402.freeq.one/tools/llm_chat.

Tags: mcp · pay-per-call · x402 · usdc · base · bazaar

Call contract

Method
POST
Input
json
Output
json
Last paid call
2026-10-13
Input example from Bazaar metadata
{
  "max_tokens": {
    "description": "Maximum tokens to generate (default 1024, max 4096). Lower values reduce cost for paid models.",
    "type": "integer"
  },
  "messages": {
    "description": "Conversation messages array",
    "items": {
      "properties": {
        "content": {
          "description": "Message text content",
          "type": "string"
        },
        "role": {
          "description": "Message role",
          "enum": [
            "system",
            "user",
            "assistant"
          ],
          "type": "string"
        }
      },
      "type": "object"
    },
    "type": "array"
  },
  "model": {
    "description": "Model ID. Examples: auto/eco/premium (free, $0.002), openai/gpt-5.2, anthropic/claude-opus-5, google/gemini-3.1-pro, deepseek/deepseek-v4-pro. Short names accepted (gpt-5.2, claude-opus-5). See /tools for full list.",
    "type": "string"
  },
  "temperature": {
    "description": "Sampling temperature 0-2 (default 0.7)",
    "type": "number"
  }
}
Output example
{
  "type": "string"
}

Use with an agent

  1. Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
  2. Inspect. Fetch /resources/28433.json for the price and payment options.
  3. Pay. Call GET https://x402.freeq.one/tools/llm_chat. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
  4. Execute. The provider returns 200 with the data. Agent Bazaar is not in the request path and never sees your payment.

For humans

You don't need an account or an API key; you need a wallet holding a small amount of USDC on Base, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price
$0.05 / request
Protocol
x402 v2
Auth
No account or API key. Pay per request.
Networks
Base
Demand
12 calls · 1 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

SchemeNetworkAssetAmountPay toTimeout
exactBase
eip155:8453
USDC$0.050x90b0dC893406d6eA63bb077ED59F5e8340f98d8460s
accepts[] (raw JSON)
[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x90b0dC893406d6eA63bb077ED59F5e8340f98d84",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "50000",
    "amountUsd": 0.05,
    "maxTimeoutSeconds": 60
  }
]

Schemas

Output schema (JSON Schema)
{
  "properties": {
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}
Example shape — generated from the schema, not a captured live response
{
  "type": "string"
}

Examples

curl
curl "https://x402.freeq.one/tools/llm_chat"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid
JavaScript
const res = await fetch("https://x402.freeq.one/tools/llm_chat");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}
Python
import httpx
res = httpx.get("https://x402.freeq.one/tools/llm_chat")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Details

Provider
x402.freeq.one
Endpoint
https://x402.freeq.one/tools/llm_chat
Machine-readable
/resources/28433.json