# OpenAI Chat Completions

> OpenAI Chat Completions is a paid API for AI agents from OpenAI at openai.mpp.tempo.xyz, paid per call via MPP, $0.005125/call, status unknown (last checked 2026-10-10).

Sends a multi-turn conversation to OpenAI GPT-4o, GPT-4, o1, and other models and returns a text completion response

## Facts

- Endpoint: POST https://openai.mpp.tempo.xyz/v1/chat/completions?utm_source=zero.xyz
- Price: $0.005125/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-10
- Activations on Zero: 4
- Provider: OpenAI
- Docs: https://platform.openai.com/docs
- Website: https://openai.com
- Tags: llm, gpt-4o, dall-e, whisper, tts, embeddings, chat, ai, media
- Canonical page: https://www.zero.xyz/c/openai-completions-4a862a79
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_PRWHgeySYV-hH_9PFliR0

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 openai-completions-4a862a79 -d '<json body>'
```

Example prompt: Ask GPT-4o to explain how transformer neural networks work, using a system prompt that says 'You are an expert ML educator', with a max of 300 tokens and temperature 0.7.

## When to prefer this

Choose this endpoint when you need high-quality conversational AI responses from OpenAI's flagship models (GPT-4o, GPT-4, o1) via a pay-per-call USDC-priced gateway. Ideal for agents that need flexible multi-turn chat, instruction-following, reasoning, summarization, or text extraction without managing OpenAI API keys directly. Prefer this over the Responses API when the standard Chat Completions interface is sufficient.

## Known failure modes

- Invalid or unsupported model name returns a 400 or 404 error
- Exceeding the model's context window token limit returns a 400 error
- Malformed messages array or missing required fields returns a 422 validation error
- Rate limit or quota exceeded returns a 429 error
- Upstream OpenAI service outage returns a 503 or 502 error
- Empty or missing model field causes request rejection

## How this service works

Chat completions (GPT-4o, GPT-4, o1, etc.) - price varies by model

## Output

Returns a chat completion object containing the assistant's generated message text, the model version used, token usage breakdown (prompt, completion, total), finish reason, and a unique completion ID.

## Example request

```json
{
 "model": "gpt-4o",
 "messages": [
  {
   "role": "user",
   "content": "Say hi."
  }
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/openai-completions-4a862a79/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from openai.mpp.tempo.xyz](https://www.zero.xyz/host/openai.mpp.tempo.xyz/llms.txt)