Fix Cain: Add /api/state endpoint for health monitoring

Root cause analysis:
- Cain's Space was running (HTTP 200) but didn't have /api/state endpoint
- Home Space was polling Cain's /api/state and getting 404 "Not Found"
- This caused Cain to show "syncing" state with "Cain is starting..." message
- The "Error: unknown" was from Home Space's health check seeing Cain as unresponsive

Changes:
1. Updated app.py to use FastAPI + Gradio integration
2. Added /api/state endpoint that returns proper agent state
3. Added /status, /health, and /agents endpoints for compatibility
4. Updated requirements.txt to include fastapi and uvicorn

Technical details:
- Agent state includes: state (idle), detail, progress, timestamps
- CORS enabled for cross-origin requests from monitoring systems
- Maintains backward compatibility with existing Gradio UI

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app.py

@@ -3,6 +3,10 @@ import os
 import sys
 import json
 import time
+import datetime
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+import uvicorn
 
 # Try importing audio libraries, but don't crash if they fail
 # We'll add audio features later if the environment supports it
@@ -14,14 +18,62 @@ except ImportError:
     AUDIO_AVAILABLE = False
     print("Audio libraries not available, running in text-only mode")
 
+# Global state for the agent
+AGENT_STATE = {
+    "state": "idle",
+    "detail": "Cain is running",
+    "progress": 100,
+    "updated_at": datetime.datetime.now().isoformat(),
+    "bubbleText": "",
+    "bubbleTextZh": "",
+    "officeName": "Cain's Office",
+    "agentId": "cain",
+    "name": "Cain",
+    "area": "breakroom",
+    "authStatus": "approved"
+}
+
+# Create FastAPI app for custom routes
+fastapi_app = FastAPI()
+
+# Add CORS middleware
+fastapi_app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+@fastapi_app.get("/api/state")
+@fastapi_app.get("/status")
+async def get_state():
+    """Return agent state for health monitoring"""
+    AGENT_STATE["updated_at"] = datetime.datetime.now().isoformat()
+    return AGENT_STATE
+
+@fastapi_app.get("/health")
+async def health_check():
+    """Simple health check endpoint"""
+    return {
+        "status": "healthy",
+        "agent": "Cain",
+        "timestamp": datetime.datetime.now().isoformat()
+    }
+
+@fastapi_app.get("/agents")
+async def get_agents():
+    """Return agents list (single agent for Cain)"""
+    return [AGENT_STATE]
+
 # Placeholder for other features
 def transcribe(audio):
     if audio is None:
         return "No audio provided"
-    
+
     if not AUDIO_AVAILABLE:
         return "Audio processing is not available in this environment"
-    
+
     try:
         # Audio processing logic here
         return "Audio processed (placeholder)"
@@ -30,6 +82,7 @@ def transcribe(audio):
 
 def chat(message, history):
     # Simple chat response
+    AGENT_STATE["updated_at"] = datetime.datetime.now().isoformat()
     return f"Cain says: {message}"
 
 # Ensure the directory exists
@@ -39,13 +92,14 @@ os.makedirs("/data/logs", exist_ok=True)
 with gr.Blocks() as demo:
     gr.Markdown("# Cain is Alive")
     gr.Markdown("Status: RUNNING")
-    
+    gr.Markdown("State API: GET /api/state or /status")
+
     with gr.Tab("Chat"):
         chat_interface = gr.ChatInterface(
             fn=chat,
             examples=["Hello", "How are you?", "Tell me a joke"]
         )
-    
+
     with gr.Tab("Audio"):
         if AUDIO_AVAILABLE:
             audio_input = gr.Audio(sources=["microphone"])
@@ -59,10 +113,24 @@ with gr.Blocks() as demo:
         else:
             gr.Markdown("Audio features are disabled in this environment")
 
+# Mount Gradio app to FastAPI
+# This allows both Gradio UI and custom API endpoints to work together
+gradio_app = gr.mount_gradio_app(fastapi_app, demo, path="/")
+
 # Launch the app
-print("Launching Gradio app on 0.0.0.0:7860...")
-demo.launch(
-    server_name="0.0.0.0",
-    server_port=7860,
-    share=False
-)
+print("Launching Gradio app with FastAPI on 0.0.0.0:7860...")
+print("Available endpoints:")
+print("  - / (Gradio UI)")
+print("  - /api/state (Agent state)")
+print("  - /status (Agent status)")
+print("  - /agents (Agent list)")
+print("  - /health (Health check)")
+
+if __name__ == "__main__":
+    import uvicorn
+    uvicorn.run(
+        gradio_app,
+        host="0.0.0.0",
+        port=7860,
+        log_level="info"
+    )

requirements.txt

@@ -1,2 +1,4 @@
 gradio>=4.0.0
-psutil
+psutil
+fastapi
+uvicorn[standard]