# PennyRail OpenAI-Compatible Embeddings

> PennyRail OpenAI-Compatible Embeddings is a paid API for AI agents from pennyrail.vercel.app, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Generates vector embeddings for input text or data using an OpenAI-compatible embeddings API, accessible via micropayment settlement

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/p/mini/ai.v1-embeddings--openai-compatible-embeddings
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennyrail-openai-compatible-embeddings-99632d7d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_lCELnFeTCZwdCVirk2dpG

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 pennyrail-openai-compatible-embeddings-99632d7d -d '<json body>'
```

Example prompt: Convert this text into an embedding vector using PennyRail's OpenAI-compatible embeddings endpoint: 'The quick brown fox jumps over the lazy dog'.

## When to prefer this

Choose this endpoint when you need OpenAI-format embeddings with per-call micropayment billing (0.002 USDC) rather than a subscription or API-key-based model. It is ideal for agents operating in x402-enabled payment ecosystems, serverless or ephemeral environments where managing API keys is undesirable, or when you need drop-in OpenAI embeddings compatibility without provisioning an OpenAI account.

## Known failure modes

- Missing or malformed 'input' field returns a validation error
- Payment of 0.002 USDC not settled via x402 protocol results in 402 Payment Required
- Empty input object may produce zero-length or error response
- Rate limiting or upstream OpenAI API errors may cause 5xx responses
- Oversized input exceeding token limits may be rejected

## How this service works

Machine-readable settlement service

## Output

Returns an object containing one or more embedding vectors (arrays of floating-point numbers) representing the semantic content of the input, in a format compatible with the OpenAI embeddings API response schema.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "additionalProperties": true
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pennyrail-openai-compatible-embeddings-99632d7d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pennyrail.vercel.app](https://www.zero.xyz/host/pennyrail.vercel.app/llms.txt)