# Llama-3.1-8B-Instruct Chat Completions (ari001)

> Llama-3.1-8B-Instruct Chat Completions (ari001) is a paid API for AI agents from ari001.tailb4ac3a.ts.net, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-02).

Runs a user-supplied message thread through Meta's Llama-3.1-8B-Instruct model and returns the assistant reply, model name, and token usage in OpenAI-compatible format.

## Facts

- Endpoint: POST https://ari001.tailb4ac3a.ts.net/v1/ventures/llm_chat_api/llm_chat_llama3_1_8b?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/llama-3-1-8b-instruct-chat-completions-ari001-11a1db88
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nnnHewVsBj2uScKABMPuU

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 llama-3-1-8b-instruct-chat-completions-ari001-11a1db88 -d '<json body>'
```

Example prompt: Ask Llama-3.1-8B-Instruct to explain the difference between supervised and unsupervised learning in two paragraphs — use a system prompt that says 'You are a concise ML tutor' and cap the response at 512 tokens.

## When to prefer this

Choose this endpoint when you need a lightweight, fast, open-source LLM (8B parameters) for chat completions without relying on OpenAI or Anthropic, especially when cost sensitivity matters ($0.003/call), when you want a pay-per-request model with no subscription, or when your workflow explicitly targets Meta's Llama-3.1-8B-Instruct capabilities. Prefer the sibling Qwen3-32B endpoint when you need stronger reasoning or a larger model.

## Known failure modes

- Message array exceeds 16,000 total characters — request rejected
- max_tokens exceeds 1024 — validation error
- Missing required 'messages' field — 400 bad request
- Empty messages array (minItems:1 violated) — validation error
- Payment not included or insufficient — x402 payment required error
- Model overloaded or host unreachable — 5xx or timeout

## Output

Returns a JSON object with: ok (boolean), message (object with role='assistant' and the generated content string), model (the Llama model identifier), and usage (prompt_tokens and completion_tokens integers). On failure, ok is false and an error string is included.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "messages"
     ],
     "properties": {
      "messages": {
       "type": "array",
       "items": {
        "type": "object",
        "required": [
         "role",
         "content"
        ],
        "properties": {
         "role": {
          "enum": [
           "system",
           "user",
           "assistant"
          ]
         },
         "content": {
          "type": "string"
         }
        }
       },
       "maxItems": 32,
       "minItems": 1
      },
      "max_tokens": {
       "type": "integer",
       "maximum": 1024,
       "minimum": 1
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "ok",
      "service"
     ],
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "error": {
       "type": "string",
       "description": "present when ok is false"
      },
      "model": {
       "type": "string"
      },
      "usage": {
       "type": "object",
       "properties": {
        "prompt_tokens": {
         "type": [
          "integer",
          "null"
         ]
        },
        "completion_tokens": {
         "type": [
          "integer",
          "null"
         ]
        }
       }
      },
      "method": {
       "type": "string"
      },
      "message": {
       "type": "object",
       "properties": {
        "role": {
         "const": "assistant"
        },
        "content": {
         "type": "string"
        }
       }
      },
      "service": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/llama-3-1-8b-instruct-chat-completions-ari001-11a1db88/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ari001.tailb4ac3a.ts.net](https://www.zero.xyz/host/ari001.tailb4ac3a.ts.net/llms.txt)