# PaySponge Embeddings API (x402 Pay-per-Call)

> PaySponge Embeddings API (x402 Pay-per-Call) is a paid API for AI agents from api.paysponge.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Generates vector embeddings for input text, gated by on-chain micro-payment via x402 (USDC on Base or SPL tokens on Solana)

## Facts

- Endpoint: POST https://api.paysponge.com/x402/purchase/svc_d5zgtpg00dvssgj28/embeddings
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-paysponge-com-06e22ad2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_20w6YBPzZTT3Qp5YJ6TPP

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 api-paysponge-com-06e22ad2 -d '<json body>'
```

Example prompt: Generate vector embeddings for the text 'the quick brown fox jumps over the lazy dog' using the PaySponge pay-per-call embeddings endpoint — I'll pay the $0.01 USDC fee on Base.

## When to prefer this

Choose this endpoint when you need vector embeddings and want to pay per-call with crypto (USDC on Base or SPL tokens on Solana) without an API subscription or API key — ideal for agents operating in Web3 contexts or autonomous payment pipelines using the x402 protocol.

## Known failure modes

- Payment not provided or insufficient — 402 Payment Required with payment instructions
- Invalid or malformed input body — 400 Bad Request
- Payment on unsupported chain or token — payment rejected
- Network congestion on Base or Solana delays payment confirmation
- Empty or missing input field — validation error

## How this service works

Service: OpenRouter API (https://api.paysponge.com/embeddings)

## Output

Returns a JSON object containing a vector embedding (array of floats) representing the semantic content of the input text, delivered after on-chain payment confirmation via x402 protocol.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "properties": {},
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "json"
    },
    "example": {
     "type": "object",
     "additionalProperties": true
    }
   },
   "additionalProperties": false
  }
 },
 "additionalProperties": false
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-paysponge-com-06e22ad2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.paysponge.com](https://www.zero.xyz/host/api.paysponge.com/llms.txt)