# QuickBuild LLM Chat Completions

> QuickBuild LLM Chat Completions is a paid API for AI agents from quickbuild.quynguyenbac.workers.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-21).

Runs a prompt or chat message history through a hosted open-source LLM (Llama, Mistral, or Granite) and returns an OpenAI-compatible chat completion response

## Facts

- Endpoint: GET https://quickbuild.quynguyenbac.workers.dev/v1/chat/completions?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/quickbuild-llm-chat-completions-8e4c3944
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WnrFkAKwRodn0wjTs7UBs

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 quickbuild-llm-chat-completions-8e4c3944
```

Example prompt: Ask the llama-3.1-8b model: 'Explain what HTTP 402 Payment Required means in one sentence' — up to 100 tokens, with temperature 0.7.

## When to prefer this

Choose this endpoint when you need cheap ($0.003/call), OpenAI-compatible LLM inference on small open-source models (Llama, Mistral, Granite) without managing infrastructure, especially for micro-tasks where GPT-4-class capability is unnecessary. Prefer it over heavier LLM APIs when cost and compatibility matter more than frontier-model quality, and when a 512-token output cap is acceptable.

## Known failure modes

- Unknown model name falls back silently to default llama-3.1-8b rather than erroring
- max_tokens hard-capped at 512 — requests for longer outputs are silently truncated
- Missing payment header (x402) returns HTTP 402 before inference runs
- Prompt or messages array omitted — falls back to a built-in sample question rather than erroring
- Stream mode delivers the full answer in one chunk, not token-by-token, despite SSE framing

## How this service works

Landing pages ($15), Google Sheets/Apps Script automation ($10), scrapers, scripts & Telegram bots (from $15), broken-link + sitemap audit reports ($10). See a working demo first, pay after.

## Output

An OpenAI-compatible chat.completion JSON object containing the assistant's reply text, the model used, token counts (prompt, completion, total), a finish_reason, and a unique completion ID. When stream=true, returns server-sent events with chat.completion.chunk objects ending with [DONE].

## 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": {
      "seed": {
       "type": "integer",
       "description": "Optional seed."
      },
      "model": {
       "enum": [
        "llama-3.1-8b",
        "llama-3.2-3b",
        "llama-3.2-1b",
        "mistral-7b",
        "granite-4.0-micro",
        "@cf/meta/llama-3.1-8b-instruct-fp8-fast",
        "@cf/meta/llama-3.2-3b-instruct",
        "@cf/meta/llama-3.2-1b-instruct",
        "@cf/mistral/mistral-7b-instruct-v0.1",
        "@cf/ibm-granite/granite-4.0-h-micro"
       ],
       "type": "string",
       "description": "Model alias or Workers AI id (default llama-3.1-8b). Unknown names fall back to the default."
      },
      "top_p": {
       "type": "number",
       "maximum": 1,
       "minimum": 0,
       "description": "Nucleus sampling."
      },
      "prompt": {
       "type": "string",
       "description": "Convenience: a single user message (appended after `messages`)."
      },
      "stream": {
       "type": "boolean",
       "description": "If true, returns text/event-stream chat.completion.chunk events (whole answer in one chunk) ending with [DONE]."
      },
      "messages": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "role",
         "content"
        ],
        "properties": {
         "role": {
          "enum": [
           "system",
           "developer",
           "user",
           "assistant"
          ],
          "type": "string"
         },
         "content": {
          "type": "string"
         }
        }
       },
       "description": "OpenAI-style chat messages. Optional: if omitted, `prompt` (or a sample question) is used."
      },
      "max_tokens": {
       "type": "integer",
       "maximum": 512,
       "minimum": 1,
       "description": "Max completion tokens (default and cap 512)."
      },
      "temperature": {
       "type": "number",
       "maximum": 2,
       "minimum": 0,
       "description": "Sampling temperature (model default if omitted)."
      },
      "response_format": {
       "
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "id": "chatcmpl-3f2a9c",
  "model": "@cf/meta/llama-3.1-8b-instruct-fp8-fast",
  "usage": {
   "total_tokens": 49,
   "prompt_tokens": 22,
   "completion_tokens": 27
  },
  "object": "chat.completion",
  "choices": [
   {
    "index": 0,
    "message": {
     "role": "assistant",
     "content": "HTTP 402 Payment Required means the server wants payment before it will serve the requested resource."
    },
    "finish_reason": "stop"
   }
  ],
  "created": 1792526400
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/quickbuild-llm-chat-completions-8e4c3944/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from quickbuild.quynguyenbac.workers.dev](https://www.zero.xyz/host/quickbuild.quynguyenbac.workers.dev/llms.txt)