Chat Completions

Test the Endpoint POST /v1/chat/completions

The Chat Completions endpoint allows you to generate text responses using the distributed language models in the Fortytwo network. It supports both standard responses and streaming via Server-Sent Events (SSE).

Create Chat Completion

Generate a response to a conversation using a specified network model’s preset.

Endpoint

POST https://api.fortytwo.network/v1/chat/completions

Request Body

string

required

ID of the model to use (from /v1/models).

array

required

List of messages in the conversation.

boolean

default:"false"

Enable Server-Sent Events streaming.

Message Format

Each message in the messages array should have:

string

required

One of: system | user | assistant.

string

required

The content of the message.

Response Modes

Standard Response Mode
Streaming Mode (SSE)

In standard mode, the API returns a complete response once generation is finished.

Example Request

curl https://api.fortytwo.network/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_FORTYTWO_API_KEY" \
  -d '{
    "model": "fortytwo-xxxxxxxxxxxx",
    "messages": [
      {
        "role": "system",
        "content": "You are a helpful assistant."
      },
      {
        "role": "user",
        "content": "What is the Fortytwo network?"
      }
    ]
  }'

import requests

api_key = "YOUR_FORTYTWO_API_KEY"
url = "https://api.fortytwo.network/v1/chat/completions"

headers = {
    "Content-Type": "application/json",
    "Authorization": f"Bearer {api_key}"
}

data = {
    "model": "fortytwo-xxxxxxxxxxxx",
    "messages": [
        {
            "role": "system",
            "content": "You are a helpful assistant."
        },
        {
            "role": "user",
            "content": "What is the Fortytwo network?"
        }
    ]
}

response = requests.post(url, headers=headers, json=data)
result = response.json()
print(result['choices'][0]['message']['content'])

const apiKey = 'YOUR_FORTYTWO_API_KEY';

const response = await fetch('https://api.fortytwo.network/v1/chat/completions', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Authorization': `Bearer ${apiKey}`
  },
  body: JSON.stringify({
    model: 'fortytwo-xxxxxxxxxxxx',
    messages: [
      {
        role: 'system',
        content: 'You are a helpful assistant.'
      },
      {
        role: 'user',
        content: 'What is the Fortytwo network?'
      }
    ]
  })
});

const data = await response.json();
console.log(data.choices[0].message.content);

Response Format

{
  "id": "chatcmpl-abc123",
  "object": "chat.completion",
  "created": 1677858242,
  "model": "fortytwo-xxxxxxxxxxxx",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "The Fortytwo network is a decentralized AI protocol that leverages swarm intelligence..."
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 25,
    "completion_tokens": 50,
    "total_tokens": 75
  }
}

Response Fields

string

Unique identifier for the completion.

string

Always chat.completion.

integer

Unix timestamp of creation.

string

Model used for generation.

array

List of completion choices.

object

Token usage information.

Enable streaming to receive tokens as they are generated, providing better user experience for real-time applications.

Example Request

curl https://api.fortytwo.network/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_FORTYTWO_API_KEY" \
  -d '{
    "model": "fortytwo-xxxxxxxxxxxx",
    "messages": [
      {
        "role": "user",
        "content": "Tell me a story"
      }
    ],
    "stream": true
  }'

import requests
import json

api_key = "YOUR_FORTYTWO_API_KEY"
url = "https://api.fortytwo.network/v1/chat/completions"

headers = {
    "Content-Type": "application/json",
    "Authorization": f"Bearer {api_key}"
}

data = {
    "model": "fortytwo-xxxxxxxxxxxx",
    "messages": [
        {"role": "user", "content": "Tell me a story"}
    ],
    "stream": True
}

response = requests.post(url, headers=headers, json=data, stream=True)

# Process the stream
for line in response.iter_lines():
    if line:
        line = line.decode('utf-8')
        if line.startswith('data: '):
            data_str = line[6:]  # Remove 'data: ' prefix
            if data_str == '[DONE]':
                break
            try:
                chunk = json.loads(data_str)
                content = chunk['choices'][0]['delta'].get('content', '')
                if content:
                    print(content, end='', flush=True)
            except json.JSONDecodeError:
                pass

const apiKey = 'YOUR_FORTYTWO_API_KEY';

const response = await fetch('https://api.fortytwo.network/v1/chat/completions', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Authorization': `Bearer ${apiKey}`
  },
  body: JSON.stringify({
    model: 'fortytwo-xxxxxxxxxxxx',
    messages: [
      { role: 'user', content: 'Tell me a story' }
    ],
    stream: true
  })
});

const reader = response.body.getReader();
const decoder = new TextDecoder();

while (true) {
  const { done, value } = await reader.read();
  if (done) break;

  const chunk = decoder.decode(value);
  const lines = chunk.split('\n');

  for (const line of lines) {
    if (line.startsWith('data: ')) {
      const data = line.slice(6);
      if (data === '[DONE]') break;

      try {
        const parsed = JSON.parse(data);
        const content = parsed.choices[0].delta.content;
        if (content) {
          process.stdout.write(content);
        }
      } catch (e) {
        // Skip invalid JSON
      }
    }
  }
}

Stream Response Format

Each chunk in the stream follows this format:

data: {"id":"chatcmpl-abc123","object":"chat.completion.chunk","created":1677858242,"model":"fortytwo-xxxxxxxxxxxx","choices":[{"index":0,"delta":{"content":"Once"},"finish_reason":null}]}

data: {"id":"chatcmpl-abc123","object":"chat.completion.chunk","created":1677858242,"model":"fortytwo-xxxxxxxxxxxx","choices":[{"index":0,"delta":{"content":" upon"},"finish_reason":null}]}

data: {"id":"chatcmpl-abc123","object":"chat.completion.chunk","created":1677858242,"model":"fortytwo-xxxxxxxxxxxx","choices":[{"index":0,"delta":{"content":" a"},"finish_reason":null}]}

data: [DONE]

The stream ends with data: [DONE] to indicate completion.

OpenAI SDK Integration

The Fortytwo API is fully compatible with the OpenAI Python and Node.js SDKs:

from openai import OpenAI

client = OpenAI(
    api_key="YOUR_FORTYTWO_API_KEY",
    base_url="https://api.fortytwo.network/v1"
)

# Standard completion
response = client.chat.completions.create(
    model="fortytwo-xxxxxxxxxxxx",
    messages=[
        {"role": "system", "content": "You are a helpful assistant."},
        {"role": "user", "content": "Hello!"}
    ]
)
print(response.choices[0].message.content)

# Streaming completion
stream = client.chat.completions.create(
    model="fortytwo-xxxxxxxxxxxx",
    messages=[
        {"role": "user", "content": "Tell me a story"}
    ],
    stream=True
)

for chunk in stream:
    if chunk.choices[0].delta.content:
        print(chunk.choices[0].delta.content, end='')

import OpenAI from 'openai';

const client = new OpenAI({
  apiKey: 'YOUR_FORTYTWO_API_KEY',
  baseURL: 'https://api.fortytwo.network/v1'
});

// Standard completion
const response = await client.chat.completions.create({
  model: 'fortytwo-xxxxxxxxxxxx',
  messages: [
    { role: 'system', content: 'You are a helpful assistant.' },
    { role: 'user', content: 'Hello!' }
  ]
});
console.log(response.choices[0].message.content);

// Streaming completion
const stream = await client.chat.completions.create({
  model: 'fortytwo-xxxxxxxxxxxx',
  messages: [
    { role: 'user', content: 'Tell me a story' }
  ],
  stream: true
});

for await (const chunk of stream) {
  process.stdout.write(chunk.choices[0]?.delta?.content || '');
}

Preview Rate Limiting

Chat completion requests are subject to rate limits while in Preview. See ‘Preview Limits & Quotas’ for more details.

Error Responses

Common error responses for chat completions can be found in ‘Errors’.

Next Steps

Learn about ‘Preview Limits & Quotas’.
Review ‘Authentication’ details.

Get Started

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Create Chat Completion

Endpoint

Request Body

Message Format

Response Modes

Example Request

Response Format

Response Fields

Example Request

Stream Response Format

OpenAI SDK Integration

Preview Rate Limiting

Error Responses

Next Steps

​Create Chat Completion

​Endpoint

​Request Body

​Message Format

​Response Modes

​Example Request

​Response Format

​Response Fields

​Example Request

​Stream Response Format

​OpenAI SDK Integration

​Preview Rate Limiting

​Error Responses

​Next Steps

Create Chat Completion

Endpoint

Request Body

Message Format

Response Modes

Example Request

Response Format

Response Fields

Example Request

Stream Response Format

OpenAI SDK Integration

Preview Rate Limiting

Error Responses

Next Steps