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Licensed to be used in conjunction with basebox, only.

OpenAI-Compatible API User Guide

The Basebox's OpenAI-compatible API endpoint.

> "The problem with quotes on the Internet is that you can never know if they are genuine." — Abraham Lincoln (probably)

Table of Contents

  1. What is This API?
  2. Getting Your API Token
  3. How to Use the API Properly
  4. Testing with curl
  5. Testing with Swagger UI
  6. Common Mistakes (and How to Avoid Them)
  7. Troubleshooting

What is This API?

In plain English: This endpoint lets you use tools and libraries designed for OpenAI's API, but they'll actually talk to Basebox's backend. It's like having a universal translator for AI APIs.

What Can You Do?

  • Chat Completions: Have conversations with AI models
  • List Models: See what models are available
  • Streaming: Get responses in real-time (like watching a typewriter in action)
  • Tool Calling: Let the AI use functions to do things (like checking the weather or querying databases)

Key Endpoints

  • POST /v1/chat/completions - Chat with AI models
  • GET /v1/models - List available models

Base URL: Your Basebox instance URL (e.g., https://your-org.basebox.ai or http://localhost:8888)

Getting Your API Token

Before you can make API calls, you need an API token.

Step-by-Step Guide

  1. Log into Basebox: Open your Basebox instance in a web browser

  2. Navigate to API Tokens:

  3. Go to the Admin section
  4. Click on "API Tokens"

  1. Create a New Token:
  2. Click the "Create Token" or "New Token" button
  3. Give it a memorable name (like "my-awesome-script" or "testing-token")
  4. Click "Create"

  1. Copy Your Token:
  2. ⚠️ IMPORTANT: The token is shown only once! Copy it immediately. ⚠️
  3. Store it securely (password manager, environment variable, etc.)
  4. If you lose it - no problem - you'll need to create a new one

Token Security Tip:

Treat your API token like your password
Never commit it to Git
Use environment variables instead

Token Format

Your token will look something like this:

aBc123XyZ456DeF789GhI012JkL345MnO678PqR901StU234VwX567YzA890

It's a long string of characters. Don't worry if it looks random - that's by design!

How to Use the API Properly

Authentication

Every API request needs authentication. You'll use Bearer token authentication:

Authorization: Bearer YOUR_TOKEN_HERE

Realm/Organization

Depending on your setup, you might need to specify which organization (realm) you're using:

Option 1: Using X-Realm Header (recommended)

X-Realm: your-org-name

Option 2: Using Subdomain If your Basebox instance is at your-org.basebox.ai, the realm is automatically extracted from the subdomain.

Basic Request Structure

Here's what a typical request looks like:

{
  "model": "claude-sonnet-4",
  "messages": [
    {
      "role": "user",
      "content": "Hello, how are you?"
    }
  ],
  "stream": false,
  "temperature": 0.7,
  "max_tokens": 500
}

Understanding the Fields

  • model: Which AI model to use (check /v1/models for available options)
  • messages: Array of conversation messages
  • role: "system", "user", "assistant", or "tool"
  • content: The actual message text
  • stream: true for streaming responses, false for complete response
  • temperature: Creativity level (0.0 = focused, 1.0 = creative)
  • max_tokens: Maximum tokens in the response

Message Roles Explained

Think of roles like characters in a play:

  • system: The director's notes - sets the AI's behavior and personality
  • user: You, the human asking questions
  • assistant: The AI's responses
  • tool: Results from function calls (if you're using tools)

Example: Multi-Turn Conversation

{
  "model": "claude-sonnet-4",
  "messages": [
    {
      "role": "system",
      "content": "You are a helpful coding assistant."
    },
    {
      "role": "user",
      "content": "What is Rust?"
    },
    {
      "role": "assistant",
      "content": "Rust is a systems programming language..."
    },
    {
      "role": "user",
      "content": "Can you give me a simple example?"
    }
  ]
}

Testing with curl

curl is like a Swiss Army knife for API testing - simple, powerful, and always there when you need it. 🔧

Prerequisites

Make sure you have:

  • curl installed (it's usually pre-installed on macOS/Linux)
  • Your API token ready
  • Your Basebox URL

Basic Chat Completion Request

curl -X POST https://your-org.basebox.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_TOKEN_HERE" \
  -H "X-Realm: your-org-name" \
  -d '{
    "model": "claude-sonnet-4",
    "messages": [
      {
        "role": "user",
        "content": "Write a haiku about APIs"
      }
    ],
    "stream": false
  }'

What You'll Get Back

A JSON response that looks like this:

{
  "id": "chatcmpl-abc123",
  "object": "chat.completion",
  "created": 1234567890,
  "model": "claude-sonnet-4",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "Endpoints await,\nBearer tokens in the breeze,\nData flows like streams."
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 12,
    "completion_tokens": 17,
    "total_tokens": 29
  }
}

Streaming Request

Want to see the response as it's generated? Use streaming:

curl -X POST https://your-org.basebox.ai/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_TOKEN_HERE" \
  -H "X-Realm: your-org-name" \
  -d '{
    "model": "claude-sonnet-4",
    "messages": [
      {
        "role": "user",
        "content": "Count to 10 slowly"
      }
    ],
    "stream": true
  }'

You'll see Server-Sent Events (SSE) streaming in:

data: {"id":"chatcmpl-...","object":"chat.completion.chunk",...}

data: {"id":"chatcmpl-...","choices":[{"delta":{"content":"1"}}]}

data: {"id":"chatcmpl-...","choices":[{"delta":{"content":" "}}]}

data: {"id":"chatcmpl-...","choices":[{"delta":{"content":"2"}}]}

...

data: [DONE]

List Available Models

curl -X GET https://your-org.basebox.ai/v1/models \
  -H "Authorization: Bearer YOUR_TOKEN_HERE" \
  -H "X-Realm: your-org-name"

Using Environment Variables (Pro Tip)

Save your token in an environment variable to avoid typing it every time:

# Set your token (add this to your ~/.bashrc or ~/.zshrc)
export BASEBOX_API_TOKEN="your-token-here"
export BASEBOX_URL="https://your-org.basebox.ai"
export BASEBOX_REALM="your-org-name"

# Now use it in curl
curl -X POST $BASEBOX_URL/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $BASEBOX_API_TOKEN" \
  -H "X-Realm: $BASEBOX_REALM" \
  -d '{
    "model": "claude-sonnet-4",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Testing with Swagger UI

What is Swagger UI?

Swagger UI is like an interactive playground for APIs. Instead of writing curl commands or code, you can:

  • Explore endpoints visually
  • Test API calls directly in your browser
  • See request/response schemas automatically
  • Try different parameters without writing code

Think of it as a "try before you code" tool. It's perfect for:

  • Learning how the API works
  • Quick testing and experimentation
  • Sharing API examples with teammates
  • Debugging issues

Fun Fact: Swagger UI generates its interface from an OpenAPI specification - a machine-readable description of the API. It's like having a map that also shows you how to use each road!

Accessing Swagger UI

  1. Open your browser and navigate to:
https://your-org.basebox.ai/v1/api/docs

Or for local development:

http://localhost:8888/v1/api/docs
2. You should see a page that looks like this:

Step-by-Step: Your First Swagger UI Request

Step 1: Authorize

Before you can make requests, you need to authenticate:

  1. Click the "Authorize" button (usually at the top right)
  2. In the popup, you'll see a field for "bearer_auth"
  3. Enter your token: YOUR_TOKEN_HERE
  4. Click "Authorize"
  5. Click "Close"

You should see a 🔒 lock icon next to the endpoints, indicating you're authenticated.

Step 2: Explore Available Models

  1. Find the "Models" section
  2. Click on "GET /v1/models"
  3. Click "Try it out"
  4. Click "Execute"

You'll see:

  • Request URL: The actual URL that was called
  • Response Code: HTTP status (200 = success!)
  • Response Body: JSON list of available models

Step 3: Make a Chat Completion Request

  1. Find the "Chat Completions" section
  2. Click on "POST /v1/chat/completions"
  3. Click "Try it out"

You'll see a request body editor with an example JSON. Modify it:

{
  "model": "claude-sonnet-4",
  "messages": [
    {
      "role": "user",
      "content": "Explain APIs like I'm 5 years old"
    }
  ],
  "stream": false,
  "temperature": 0.7,
  "max_tokens": 200
}
  1. Click "Execute"
  2. Scroll down to see the response!

Understanding Swagger UI Features

Schema Documentation

Each endpoint shows:

  • Parameters: What you can send
  • Request Body: The JSON structure expected
  • Response: What you'll get back
  • Example Values: Pre-filled examples to get you started

Testing Different Scenarios

Try these in Swagger UI:

1. Simple Question:

{
  "model": "claude-sonnet-4",
  "messages": [{"role": "user", "content": "Hello!"}]
}

2. System Message:

{
  "model": "claude-sonnet-4",
  "messages": [
    {"role": "system", "content": "You are a pirate."},
    {"role": "user", "content": "Tell me about APIs"}
  ]
}

3. Multi-Turn Conversation:

{
  "model": "claude-sonnet-4",
  "messages": [
    {"role": "user", "content": "What is 2+2?"},
    {"role": "assistant", "content": "2+2 equals 4."},
    {"role": "user", "content": "What about 2+3?"}
  ]
}

Pro Tips for Swagger UI

  1. Copy as cURL: After executing a request, Swagger UI can show you the equivalent curl command - great for learning!

  2. Schema Validation: Swagger UI validates your JSON before sending - catch errors early!

  3. Response Examples: Expand the "Example Value" sections to see what responses look like

  4. Error Testing: Try invalid requests to see what error responses look like

Troubleshooting Swagger UI

Problem: "401 Unauthorized"
Solution: Make sure you clicked "Authorize" and entered your token correctly (including "Bearer ")

Problem: "404 Not Found"
Solution: Check that your URL is correct - should end with /v1/api/docs

Problem: Can't see the "Authorize" button
Solution: Some browsers block popups - check your browser settings

Problem: Token not persisting
Solution: Swagger UI saves tokens in browser storage - try refreshing the page

Common Mistakes (and How to Avoid Them)

Mistake #1: Forgetting the "Bearer" Prefix

[-] Wrong:

Authorization: YOUR_TOKEN_HERE

[+] Right:

Authorization: Bearer YOUR_TOKEN_HERE

Why it matters: The API expects "Bearer" followed by a space, then your token. Without it, authentication fails.

Mistake #2: Missing Content-Type Header

[-] Wrong:

curl -X POST ... -d '{"model": "..."}'

[+] Right:

curl -X POST ... \
  -H "Content-Type: application/json" \
  -d '{"model": "..."}'

Why it matters: The server needs to know you're sending JSON, not form data.

Mistake #3: Wrong Message Role

[-] Wrong:

{
  "role": "human",  // This doesn't exist!
  "content": "Hello"
}

[+] Right:

{
  "role": "user",  // Use "user" for human messages
  "content": "Hello"
}

Valid roles: "system", "user", "assistant", "tool"

Mistake #4: Forgetting the Realm

If your setup requires it:

[-] Wrong:

curl ... -H "Authorization: Bearer TOKEN"
# Missing X-Realm header

[+] Right:

curl ... \
  -H "Authorization: Bearer TOKEN" \
  -H "X-Realm: your-org-name"

Mistake #5: Invalid JSON

[-] Wrong:

{
  "model": "claude-sonnet-4",
  "messages": [
    {"role": "user", "content": "Hello"}  // Missing comma
    {"role": "assistant", "content": "Hi"}
  ]
}

[+] Right:

{
  "model": "claude-sonnet-4",
  "messages": [
    {"role": "user", "content": "Hello"},
    {"role": "assistant", "content": "Hi"}
  ]
}

Pro tip: Use a JSON validator or your editor's JSON mode to catch these errors.

Mistake #6: Using Wrong Model Name

[-] Wrong:

{
  "model": "gpt-4",  // This model might not exist in your setup
  ...
}

[+] Right:

{
  "model": "claude-sonnet-4",  // Check /v1/models first!
  ...
}

Always check /v1/models to see what models are available.

Troubleshooting

"The problem with troubleshooting is that trouble shoots back." — Unknown

Error: 401 Unauthorized

What it means: Your token is invalid or missing.

Solutions:

  1. Check that you included "Bearer " before your token
  2. Verify your token is correct (copy-paste it again)
  3. Make sure the token hasn't been deleted
  4. Check that REST API is enabled in your Basebox instance

Error: 403 Forbidden

What it means: Your organization doesn't have a valid license or permission.

Solutions:

  1. Check your organization's license status
  2. Contact your administrator
  3. Verify you're using the correct realm/organization

Error: 400 Bad Request

What it means: Your request format is incorrect.

Solutions:

  1. Validate your JSON (use a JSON validator)
  2. Check that required fields are present (model, messages)
  3. Verify message roles are valid ("user", "assistant", etc.)
  4. Check the Swagger UI schema for the correct format

Error: 404 Not Found

What it means: The endpoint doesn't exist or the URL is wrong.

Solutions:

  1. Verify your base URL is correct
  2. Check that the path is /v1/chat/completions (not /api/v1/...)
  3. Ensure the OpenAI API is enabled on your instance

Error: 500 Internal Server Error

What it means: Something went wrong on the server side.

Solutions:

  1. Check server logs (if you have access)
  2. Try again - might be a temporary issue
  3. Contact support with:
  4. Your request (without the token!)
  5. The error response
  6. Timestamp of when it happened

Streaming Issues

Problem: Streaming responses stop abruptly

Solutions:

  1. Check your network connection
  2. Increase timeout settings in your client
  3. Verify the model supports streaming
  4. Check server logs for errors

Model Not Found

Error: Model "xyz" not found

Solutions:

  1. Call /v1/models to see available models
  2. Check model name spelling (case-sensitive!)
  3. Verify the model is configured for your organization

Quick Reference

Endpoints

Method Endpoint Description
POST /v1/chat/completions Chat with AI models
GET /v1/models List available models
GET /v1/api/docs Swagger UI documentation

Required Headers

Content-Type: application/json
Authorization: Bearer YOUR_TOKEN_HERE
X-Realm: your-org-name  (if required)

Minimum Request

{
  "model": "claude-sonnet-4",
  "messages": [
    {"role": "user", "content": "Hello"}
  ]
}

Quick curl Template

curl -X POST YOUR_URL/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_TOKEN" \
  -H "X-Realm: YOUR_REALM" \
  -d '{
    "model": "claude-sonnet-4",
    "messages": [{"role": "user", "content": "YOUR_MESSAGE"}]
  }'

Next Steps

Now that you've mastered the basics:

  1. Explore Tool Calling: Learn how to make the AI use functions
  2. Optimize Your Requests: Experiment with temperature, max_tokens, etc.
  3. Build an Integration: Use your favorite programming language's OpenAI client library
  4. Read the Architecture Docs: Check out openai-api-architecture.md for deep technical details

Final Thoughts

"The early bird might get the worm, but the second mouse gets the cheese." — Unknown

Happy coding! 🚀

Last updated: January 2026
Questions? Check the architecture documentation or contact support.