diff --git a/README.md b/README.md
new file mode 100644
index 0000000..e9b3614
--- /dev/null
+++ b/README.md
@@ -0,0 +1,64 @@
+# GPTKit
+
+GPTKit is a unified backend designed to provide tools via HTTP Actions for Custom GPTs.
+
+## Tools
+
+### WHOIS (`/domain/whois`)
+
+Allows checking domain name availability and retrieving WHOIS information.
+
+- **Endpoint**: `GET /domain/whois`
+- **Parameters**:
+  - `domain` (required): The domain name to check (e.g., `google.com`).
+  - `force` (optional): `1` to force a fresh WHOIS lookup (ignores cache).
+- **Features**:
+  - Persistent cache (SQLite).
+  - Rate limiting (global and per domain).
+  - Automatic availability parsing for major TLDs.
+
+## Deployment
+
+### Docker Compose
+
+Here is an example `docker-compose.yml` configuration to deploy GPTKit.
+
+> **Note**: The image is available on GHCR. Make sure to replace `your-username` with your GitHub username.
+
+```yaml
+services:
+  gptkit:
+    image: ghcr.io/your-username/gptkit:latest
+    restart: unless-stopped
+    ports:
+      - "8000:8000"
+    environment:
+      # Database path inside the container
+      - DB_PATH=/app/data/whois_cache.db
+    volumes:
+      # Data persistence (WHOIS cache)
+      - ./gptkit_data:/app/data
+```
+
+### Environment Variables
+
+| Variable | Description | Default |
+|----------|-------------|--------|
+| `DB_PATH` | Path to the SQLite database file | `whois_cache.db` |
+
+## Development
+
+1. **Installation**:
+   ```bash
+   pip install -r requirements.txt
+   ```
+
+2. **Run**:
+   ```bash
+   uvicorn app.main:app --reload
+   ```
+
+3. **Tests**:
+   ```bash
+   curl "http://localhost:8000/domain/whois?domain=example.com"
+   ```
diff --git a/app/services/cache.py b/app/services/cache.py
index c6f0151..abb2478 100644
--- a/app/services/cache.py
+++ b/app/services/cache.py
@@ -2,9 +2,11 @@
 from datetime import datetime, timezone
 from typing import Optional, Dict, Any
 
+import os
+
 class WhoisCache:
-    def __init__(self, db_path: str = "whois_cache.db"):
-        self.db_path = db_path
+    def __init__(self, db_path: str = None):
+        self.db_path = db_path or os.getenv("DB_PATH", "whois_cache.db")
         self._init_db()
 
     def _init_db(self):