Embeddings (OpenAI-compatible)

OpenAI-compatible text embeddings over x402 — point any OpenAI SDK at base_url https://agent402.tools/v1 and pay $0.002 per call in USDC, no API key, no signup. Batch up to 64 inputs / 16k chars per request; text-embedding-3-small by default (3-large and ada-002 supported; dimensions and encoding_format pass through). Embeddings are deterministic, so a byte-identical repeat within 10 minutes is served FREE from cache automatically (X-Cache: hit; opt out with cache:false).

Input

Example output

{
  "object": "list",
  "data": [
    {
      "object": "embedding",
      "index": 0,
      "embedding": [
        0.0023,
        -0.0091,
        0.0152
      ]
    }
  ],
  "model": "text-embedding-3-small",
  "usage": {
    "prompt_tokens": 12,
    "total_tokens": 12
  }
}

Try it — see the 402 challenge (free)

curl -i -X POST https://agent402.tools/v1/embeddings \
  -H "Content-Type: application/json" \
  -d '{"input":"Agent402 is an open-source x402 tool server."}'

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/v1/embeddings", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "input": "Agent402 is an open-source x402 tool server."
  }),
});

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