app.py

import os
from fastapi import FastAPI, HTTPException
from pydantic import BaseModel
from langchain_google_genai import ChatGoogleGenerativeAI
from browser_use import Agent

app = FastAPI()

class Task(BaseModel):
    task: str

def make_llm():
    # LangChain helper; will raise if GOOGLE_API_KEY missing
    # return ChatGoogleGenerativeAI(model="gemini-2.0-flash-exp")
    
    # Allow override from HF Secrets, but fall back to a stable, supported model
    model_id = os.getenv("GEMINI_MODEL", "gemini-1.5-pro-latest")
    return ChatGoogleGenerativeAI(
        model=model_id,
        max_retries=3,          # built-in exponential back-off
        temperature=0.2,
    )

@app.post("/run")
async def run_task(t: Task):
    try:
        llm = make_llm()
        agent = Agent(task=t.task, llm=llm)   # Browser-Use agent
        result = await agent.run_async()      # async version
        return result                         # Browser-Use returns dict
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))