Add health endpoint and cold-start wake guidance

README.md

@@ -49,6 +49,35 @@ Built with:
 
 Deploy to Hugging Face Spaces with Docker support enabled.
 
+## Health And Wake-Up Endpoint
+
+To support cold-start recovery on free-tier Hugging Face Spaces, this backend exposes:
+
+- `GET /health`
+
+This endpoint is lightweight and intended for:
+
+- frontend wake-up checks before user requests,
+- retry logic diagnostics,
+- optional cron-based warm-up pings.
+
+Example:
+
+```bash
+curl https://<your-space>.hf.space/health
+```
+
+Typical response:
+
+```json
+{
+	"status": "ok",
+	"service": "llm-excel-plotter-agent",
+	"uptime_seconds": 12.34,
+	"timestamp": 1700000000
+}
+```
+
 ---
 
 For more information, visit the [project repository](https://github.com/priyansh-saxena1/LLM-Integrated-Excel-Plotter-App)

app.py

@@ -35,6 +35,7 @@ app.config['UPLOAD_FOLDER']        = UPLOAD_FOLDER
 app.config['MAX_CONTENT_LENGTH']   = MAX_UPLOAD_BYTES
 
 os.makedirs(UPLOAD_FOLDER, exist_ok=True)
+STARTED_AT = time.time()
 
 
 def allowed_file(filename):
@@ -46,7 +47,18 @@ def index():
     return jsonify({
         "status": "ok",
         "message": "AI Data Visualization API",
-        "endpoints": ["/plot", "/upload", "/stats", "/models"]
+        "endpoints": ["/health", "/plot", "/upload", "/stats", "/models"]
+    })
+
+
+@app.route('/health', methods=['GET'])
+def health():
+    """Lightweight endpoint used by frontend wake-up checks and cron pings."""
+    return jsonify({
+        "status": "ok",
+        "service": "llm-excel-plotter-agent",
+        "uptime_seconds": round(time.time() - STARTED_AT, 2),
+        "timestamp": int(time.time()),
     })