Update app.py

app.py

@@ -1,50 +1,79 @@
-import pathlib
+"""
+app.py — Gradio front‑end + smolagents CodeAgent
+================================================
+
+This version avoids private/gated models and works on any free Hugging Face
+Space **without extra secrets**.  It relies on:
+
+* `mcp_server.py` sitting next to this file
+* A public chat‑completion capable model exposed via the HF Inference API
+  (defaults to **microsoft/Phi‑3‑mini‑4k‑instruct**, ~3 B params, free‑tier‑OK)
+* `smolagents[mcp]` for the agent loop
+* **Optional**: set `HF_MODEL_ID` or `HF_API_TOKEN` in **Settings → Secrets**
+  if you want a different (or gated) model.
+
+If you hit the free‑tier rate‑limit you can still point to OpenAI by setting the
+env var `OPENAI_API_KEY` — the code will auto‑switch to OpenAI chat.
+"""
 import os
+import pathlib
 import gradio as gr
 from mcp import StdioServerParameters
 from smolagents import MCPClient, CodeAgent, InferenceClientModel
 
-# Absolute path to sibling mcp_server.py
+# ---------- Tool server ------------------------------------------------------
 SERVER_PATH = pathlib.Path(__file__).with_name("mcp_server.py")
 
-# Lazy‑load a Hugging Face Inference model (defaults to Qwen if no id given)
-HF_MODEL_ID = os.getenv("HF_MODEL_ID", "smolagents/Qwen2.5-VL-3B-Instruct-Agentic")  # small & free-tier friendly
+# ---------- Model selection --------------------------------------------------
+# 1) Use OpenAI automatically if OPENAI_API_KEY is set.
+# 2) Otherwise fall back to a public HF Inference model that supports chat‑completion.
+OPENAI_KEY = os.getenv("OPENAI_API_KEY")
+HF_MODEL_ID = os.getenv("HF_MODEL_ID", "microsoft/Phi-3-mini-4k-instruct")
+
+if OPENAI_KEY:
+    from smolagents.models import OpenAIChatModel  # lazy import only if needed
+    BASE_MODEL = OpenAIChatModel()  # defaults gpt‑4o‑preview
+else:
+    BASE_MODEL = InferenceClientModel(model_id=HF_MODEL_ID)
 
 
+# ---------- Gradio callback ---------------------------------------------------
 def respond(message: str, history: list):
-    """Route the prompt through an MCP‑enabled CodeAgent and return the answer."""
+    """Run the user prompt through a CodeAgent that can call MCP SQL tools."""
     params = StdioServerParameters(command="python", args=[str(SERVER_PATH)])
 
     with MCPClient(params) as tools:
-        model = InferenceClientModel(model_id=HF_MODEL_ID)
-        agent = CodeAgent(tools=tools, model=model)
+        agent = CodeAgent(tools=tools, model=BASE_MODEL)
         answer = agent.run(message)
 
-    # Update chat in OpenAI‑style messages
+    # Append to chat history (OpenAI messages format)
     history.append({"role": "user", "content": message})
     history.append({"role": "assistant", "content": answer})
     return history, history
 
 
+# ---------- UI ---------------------------------------------------------------
 with gr.Blocks(title="Enterprise SQL Agent") as demo:
     chat_state = gr.State([])
-    chatbot = gr.Chatbot(type="messages", label="Enterprise SQL Agent")
+    gr.Markdown("## Enterprise SQL Agent — ask natural‑language questions about your data 🏢➡️📊")
 
-    textbox = gr.Textbox(
-        placeholder="Ask: Who are my inactive Northeast customers?",
-        show_label=False,
-    )
+    chatbot = gr.Chatbot(type="messages", label="Chat")
+    textbox = gr.Textbox(placeholder="e.g. Who are my inactive Northeast customers?", show_label=False)
     textbox.submit(respond, [textbox, chat_state], [chatbot, chat_state])
 
+    with gr.Accordion("Example prompts"):
+        gr.Markdown(
+            """
+            * Who are my **Northeast** customers with no orders in 6 months?
+            * List customers sorted by **LastOrderDate**.
+            * Draft re‑engagement emails for inactive accounts.
+            """
+        )
+
     gr.Markdown(
-        """
-        ### Example Prompts
-        - Who are my Northeast customers who haven’t ordered in 6 months?
-        - List customers sorted by last order date.
-        - Find clients from the West with recent orders.
-
-        _Powered by smolagents + MCP + Hugging Face Inference API_
-        """
+        "_Powered by MCP + smolagents + Gradio • Model: {}_".format(
+            "OpenAI (gpt‑4o)" if OPENAI_KEY else HF_MODEL_ID
+        )
     )
 
 if __name__ == "__main__":