app.py

import os
import requests
from fastapi import FastAPI, HTTPException
from fastapi.responses import JSONResponse

# -------------------------------------------------
# CONFIGURATION
# -------------------------------------------------
HUGGINGFACE_BACKEND = os.getenv("SAP_BACKEND_URL", "https://pd03-agentkit.hf.space/purchase-orders")

app = FastAPI(
    title="SAP MCP Server",
    description=(
        "Minimal MCP-compatible FastAPI server that exposes a tool to fetch SAP "
        "purchase orders from the Hugging Face backend."
    ),
    version="1.0.0",
)

# -------------------------------------------------
# MCP Manifest (for AgentKit autodiscovery)
# -------------------------------------------------
@app.get("/.well-known/mcp/manifest.json", include_in_schema=False)
async def get_manifest():
    """Returns MCP manifest so AgentKit can auto-discover the tool."""
    manifest = {
        "name": "sap_mcp_server",
        "description": "MCP server exposing a tool for retrieving SAP purchase orders.",
        "version": "1.0.0",
        "tools": [
            {
                "name": "get_purchase_orders",
                "description": "Fetches the top 50 purchase orders from the SAP Sandbox API "
                               "via the Hugging Face backend.",
                "input_schema": {"type": "object", "properties": {}},
                "output_schema": {"type": "object"},
                "http": {
                    "method": "GET",
                    "url": "/tools/get_purchase_orders"
                }
            }
        ]
    }
    return JSONResponse(content=manifest)


# -------------------------------------------------
# Tool Endpoint
# -------------------------------------------------
@app.get("/tools/get_purchase_orders", tags=["MCP Tools"])
async def get_purchase_orders():
    """
    Fetch the top 50 SAP purchase orders from your Hugging Face backend.
    This endpoint is exposed as an MCP tool for AgentKit.
    """
    try:
        resp = requests.get(HUGGINGFACE_BACKEND, timeout=30)
        resp.raise_for_status()
        return resp.json()
    except requests.exceptions.RequestException as e:
        raise HTTPException(status_code=500, detail=f"Failed to call backend: {e}")


# -------------------------------------------------
# Health Route
# -------------------------------------------------
@app.get("/health", tags=["System"])
async def health():
    return {"status": "ok", "message": "SAP MCP Server is running"}