Claude Code API

OpenAI-compatible API wrapper for Claude Code CLI. Enables any OpenAI-compatible client (like opencode) to use Claude Code's full capabilities including file editing, bash execution, and tool use.

Features

• OpenAI-compatible API - Works with any client that supports OpenAI's chat completions API
• Hybrid pool architecture - Hot workers for active conversations, automatic eviction of idle workers
• Conversation persistence - Sessions saved to disk, can be resumed later
• Streaming support - Real-time SSE streaming responses
• Docker ready - Easy deployment with Docker Compose

Quick Start

1. Clone and configure:

   cd claude-code-api
   cp .env.example .env
   # Edit .env and add your ANTHROPIC_API_KEY

2. Start with Docker Compose:

   docker-compose up -d

3. Test the API:

   curl http://localhost:3000/health
   
   curl -X POST http://localhost:3000/v1/chat/completions \
     -H "Content-Type: application/json" \
     -d '{"model":"claude-code","messages":[{"role":"user","content":"Hello!"}]}'

API Endpoints

Chat Completions (OpenAI-compatible)

POST /v1/chat/completions

Request:

{
  "model": "claude-code",
  "messages": [
    {"role": "system", "content": "You are a helpful assistant."},
    {"role": "user", "content": "Hello!"}
  ],
  "stream": false
}

Conversation ID: Specify via:

• X-Conversation-ID header (recommended)
• Model suffix: "model": "claude-code:my-conversation"
• Auto-generated if not provided

Other Endpoints

Endpoint	Method	Description
/health	GET	Health check and stats
/v1/models	GET	List available models
/conversations	GET	List active conversations
/conversations/:id	DELETE	Evict a conversation

Configuration with opencode

Add to your opencode.json:

{
  "provider": {
    "claude-code": {
      "npm": "@ai-sdk/openai-compatible",
      "options": {
        "baseURL": "http://localhost:3000/v1"
      },
      "models": {
        "claude-code": {
          "limit": {
            "context": 200000,
            "output": 64000
          }
        }
      }
    }
  }
}

Environment Variables

Variable	Default	Description
ANTHROPIC_API_KEY	(required)	Your Anthropic API key
POOL_SIZE	5	Maximum concurrent workers
IDLE_TIMEOUT_MS	300000	Worker idle timeout (5 min)
PORT	3000	Server port
WORKSPACE_DIR	/workspace	Working directory for Claude

Architecture

┌─────────────────────────────────────────────────────────────┐
│                     Docker Container                         │
│                                                              │
│  ┌────────────────────────────────────────────────────┐     │
│  │           Express.js API Server (server.js)         │     │
│  │  POST /v1/chat/completions (OpenAI-compatible)     │     │
│  └────────────────────────┬───────────────────────────┘     │
│                           │                                  │
│  ┌────────────────────────▼───────────────────────────┐     │
│  │           Hybrid Pool Manager (pool.js)             │     │
│  │  - Session affinity routing                         │     │
│  │  - LRU eviction when at capacity                   │     │
│  │  - Automatic idle cleanup                          │     │
│  └────────────────────────┬───────────────────────────┘     │
│                           │                                  │
│  ┌────────────────────────▼───────────────────────────┐     │
│  │           Claude Code Workers (worker.js)           │     │
│  │  ┌─────────┐  ┌─────────┐  ┌─────────┐            │     │
│  │  │Worker 1 │  │Worker 2 │  │Worker 3 │  ...       │     │
│  │  │conv-abc │  │conv-xyz │  │ (idle)  │            │     │
│  │  └─────────┘  └─────────┘  └─────────┘            │     │
│  │                                                     │     │
│  │  claude -p --input-format stream-json              │     │
│  │           --output-format stream-json              │     │
│  │           --session-id <conversation-id>           │     │
│  └─────────────────────────────────────────────────────┘     │
│                                                              │
│  Session Storage: /root/.claude/                             │
└──────────────────────────────────────────────────────────────┘

Development

Run locally (without Docker):

npm install
export ANTHROPIC_API_KEY=sk-ant-...
npm start

Run with file watching:

npm run dev

License

MIT