# OpenAI-Compatible Flat-Rate Chat Completions

> OpenAI-Compatible Flat-Rate Chat Completions is a paid API for AI agents from flat-rate-llm.kikoribera03.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-31).

Delivers LLM chat completions using the OpenAI API request/response format at a fixed per-call price with no token metering, no API key, and automatic model failover.

## Facts

- Endpoint: GET https://flat-rate-llm.kikoribera03.workers.dev/v1/chat/completions?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/openai-compatible-flat-rate-chat-completions-a992f912
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ms2cazCJbX78g8qU72-JQ

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-compatible-flat-rate-chat-completions-a992f912
```

Example prompt: Can you ask an LLM to write a short cover letter for a software engineering role? Use a flat-rate call — one fixed price, no token counting — and set max_tokens to 300 with a temperature of 0.7.

## When to prefer this

Choose this endpoint when you need OpenAI-compatible chat completions with perfectly predictable per-call pricing — ideal for agents that make many short or variable-length calls and want to avoid token-metering surprises. Also ideal when you have an existing OpenAI client and want zero code changes, or when uptime matters and you want automatic multi-model failover without managing it yourself. Less suitable for very high-volume batch workloads where per-token pricing would be cheaper than per-call.

## Known failure modes

- Model backend unavailable despite failover (returns error after all models exhausted)
- Payment not confirmed — completion not delivered, charge not incurred
- Malformed messages JSON in query string (parse error returned)
- max_tokens exceeds 4000 cap (clamped or rejected)
- Network timeout on the Cloudflare Worker side

## How this service works

Chat completions with the exact request and response shape of the OpenAI API: point your existing client at this URL and it works, no code change. One flat price per call whatever the size of the prompt or the answer — no token metering, no API key, no account, no rate limit. Automatic failover across several large models, so a model being down is not your problem. You are only charged if the completion is delivered.

## Output

Returns an OpenAI-format chat completion object containing the assistant's message, finish reason, and model metadata — identical in shape to an OpenAI /v1/chat/completions response, so existing OpenAI SDK clients can consume it without modification.

## 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"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "model": {
       "type": "string",
       "description": "Ignored on purpose: the service picks the model and fails over between several. Accepted so an OpenAI client can send it unchanged."
      },
      "prompt": {
       "type": "string",
       "description": "Shortcut for a single user message, if you do not want to build the array."
      },
      "messages": {
       "type": "string",
       "description": "The conversation, as in the OpenAI API: [{\"role\":\"system|user|assistant\",\"content\":\"...\"}]. In a POST, send it as a real JSON array, exactly as an OpenAI client does; in a GET, pass that same JSON as text in the query string. Both are accepted."
      },
      "max_tokens": {
       "type": "number",
       "description": "Output token cap, up to 4000. Does not change the price."
      },
      "temperature": {
       "type": "number",
       "description": "Passed through to the model when given."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/openai-compatible-flat-rate-chat-completions-a992f912/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from flat-rate-llm.kikoribera03.workers.dev](https://www.zero.xyz/host/flat-rate-llm.kikoribera03.workers.dev/llms.txt)