# GPT Chat Completions via gpt.558686.xyz

> GPT Chat Completions via gpt.558686.xyz is a paid API for AI agents from gpt.558686.xyz, paid per call via x402, $0.05/call, status unknown (last checked 2026-10-02).

Accepts a natural language prompt and returns an AI-generated chat completion response via a GPT-compatible endpoint.

## Facts

- Endpoint: GET https://gpt.558686.xyz/v1/chat/completions?utm_source=zero.xyz
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/gpt-chat-completions-via-gpt-558686-xyz-4c002c64
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WYrbCDN6Mo3XxXEC7Ysme

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 gpt-chat-completions-via-gpt-558686-xyz-4c002c64
```

Example prompt: Can you use the GPT chat completions endpoint to answer this question: 'What are three effective strategies for reducing customer churn in a SaaS business?'

## When to prefer this

Choose this endpoint when you need a pay-per-call GPT-compatible chat completion without managing API keys or subscriptions, and you are already operating in an x402 micropayment-enabled agent environment. It is suitable for lightweight agentic tasks where per-call billing at $0.05 USDC is acceptable.

## Known failure modes

- Missing or empty input prompt returns an error or empty response
- Payment not fulfilled via x402 protocol results in 402 Payment Required
- Malformed params object may cause unexpected behavior or ignored parameters
- Model unavailable or backend timeout may result in a 503 or timeout error
- Rate limiting may apply if the endpoint is overloaded

## Output

Returns an AI-generated text completion responding to the provided prompt. The response typically mirrors the format of an OpenAI chat completions API response, containing the model's generated message text based on the input task or question.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "type": "string",
   "description": "One of gpt-6-sol, gpt-6-astra, gpt-5.5, gpt-5.6-sol, gpt-5.6-terra (defaults to gpt-6-sol)"
  },
  "stream": {
   "type": "boolean",
   "description": "Streaming is accepted but currently delivered as a single response"
  },
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role",
     "content"
    ],
    "properties": {
     "role": {
      "enum": [
       "system",
       "user",
       "assistant",
       "tool"
      ],
      "type": "string"
     },
     "content": {
      "type": "string"
     }
    }
   },
   "minItems": 1,
   "description": "OpenAI-style messages array (required)"
  },
  "max_tokens": {
   "type": "integer"
  },
  "temperature": {
   "type": "number"
  },
  "response_format": {
   "type": "object"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/gpt-chat-completions-via-gpt-558686-xyz-4c002c64/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from gpt.558686.xyz](https://www.zero.xyz/host/gpt.558686.xyz/llms.txt)