Quick Start

API Documentation

Get started with the CLEX unified API in under 60 seconds. Access models through a single endpoint with provider routing handled by CLEX.

# Base URL for all CLEX API calls
CLEX_BASE_URL="https://api.clex.in/v1"

# Your CLEX API key (set as environment variable)
CLEX_API_KEY="clex_xxxxxxxxxxxxxxxxxxxx"

curl https://api.clex.in/v1/chat/completions \
  -H "Authorization: Bearer $CLEX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "meta/llama-3.3-70b-instruct",
    "messages": [
      {"role": "user", "content": "Hello!"}
    ]
  }'

# Install OpenAI SDK if not already
npm install openai

# Run your script
CLEX_API_KEY="clex_xxx" node app.js

# You are now running on CLEX proxy

Authentication

CLEX uses CLEX API keys for authentication. The CLEX routing layer handles upstream provider credentials and normalization.

// Send your CLEX API key as a Bearer token
Authorization: Bearer clex_xxxxxxxxxxxxxxxxxxxx

Chat Completions

The primary endpoint for generating AI responses. Compatible with the OpenAI chat completions format.

In this docs page, the API Explorer uses local /api/chat as a proxy for https://api.clex.in/v1/chat/completions.

Use https://api.clex.in/v1/chat/completions from code, cURL, Postman, or the OpenAI SDK. For browser navigation and API keys, go to api.clex.in.

Request Body

Response Format

Responses follow the OpenAI-compatible format. When streaming is enabled (default), responses arrive as Server-Sent Events.

{
  "id": "chatcmpl-abc123",
  "object": "chat.completion",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "Hello! How can I help you today?"
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 12,
    "completion_tokens": 9,
    "total_tokens": 21
  }
}

Streaming

Streaming uses Server-Sent Events (SSE). Each event contains a JSON object with the incremental token. The stream is terminated by a data: [DONE] event.

// Each SSE line:
data: {"choices":[{"delta":{"content":"Hello"}}]}

data: {"choices":[{"delta":{"content":" world"}}]}

data: [DONE]

Available Models

CLEX provides access to models models. Browse the full catalog on the Models page. Popular picks:

Code Examples

import requests
import json
import os

url = "https://api.clex.in/v1/chat/completions"

payload = {
    "model": "meta/llama-3.3-70b-instruct",
    "messages": [
        {"role": "user", "content": "What is quantum computing?"}
    ],
    "temperature": 0.7,
    "max_tokens": 1024
}

# Streaming response
headers = {"Authorization": f"Bearer {os.environ['CLEX_API_KEY']}"}
response = requests.post(url, json=payload, headers=headers, stream=True)

for line in response.iter_lines():
    if line:
        line = line.decode('utf-8')
        if line.startswith('data: '):
            data = line[6:]
            if data == '[DONE]':
                break
            chunk = json.loads(data)
            content = chunk['choices'][0]['delta'].get('content', '')
            print(content, end='')

const response = await fetch('https://api.clex.in/v1/chat/completions', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer ' + process.env.CLEX_API_KEY,
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    model: 'meta/llama-3.3-70b-instruct',
    messages: [
      { role: 'user', content: 'What is quantum computing?' }
    ]
  })
});

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]') continue;
      const parsed = JSON.parse(data);
      const token = parsed.choices?.[0]?.delta?.content;
      if (token) process.stdout.write(token);
    }
  }
}

curl https://api.clex.in/v1/chat/completions \
  -X POST \
  -H "Authorization: Bearer $CLEX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "meta/llama-3.3-70b-instruct",
    "messages": [
      {
        "role": "user",
        "content": "Explain quantum computing in simple terms"
      }
    ],
    "temperature": 0.7,
    "max_tokens": 1024,
    "stream": true
  }'

Error Handling

Errors return a standardized JSON object containing an error field with descriptive information, helping developers debug integrations quickly.

{
  "error": {
    "message": "Model 'meta/llama-nonexistent' is not available. Check /v1/models for supported models.",
    "type": "upstream_error",
    "code": "provider_error",
    "status": 404
  }
}

Rate Limits

Rate limits are determined by your CLEX plan and current provider capacity. Typical starter limits are:

Tutorials & Guides

Kickstart your production workflow with these step-by-step onboarding guides.

API Changelog & Versioning

CLEX endpoints follow semantic versioning. Breaking changes will always be introduced under a new version prefix (e.g. /v2/chat/completions). Below are recent platform updates.