Building Your First AI Agent in Python with the OpenAI Agents SDK

import os import sys

from agents import Agent, Runner, SQLiteSession, WebSearchTool from agents.decorators import tool

@tool def calculate_total( price: float, quantity: int ) -> float: """Calculate the total cost of an order."""

return price * quantity

def main() -> None: if not os.environ.get("OPENAI_API_KEY"): sys.exit( "Error: set the OPENAI_API_KEY environment variable first." )

agent = Agent( name="Assistant", instructions=""" Help the user with research and calculations. Use the available tools when necessary. """, tools=[ WebSearchTool(), calculate_total, ], )

session = SQLiteSession( "user_1", "conversations.db" )

try: while True: try: message = input("You: ") except (EOFError, KeyboardInterrupt): print() break

command = message.strip().lower()

if command in {"exit", "quit"}: break

if not command: continue

try: result = Runner.run_sync( agent, message, session=session, ) except Exception as exc: print( f"Agent error " f"({type(exc).name}): {exc}" ) continue

print("Agent:", result.final_output)

finally: session.close()

if name == "main": main()

This gives us a small but complete conversational agent with web search, a custom Python tool, persistent memory, basic error handling, and a continuous chat interface.

The Agents SDK also enables tracing by default, which is especially useful once your workflows become more complex. Traces let you inspect the model calls, tool usage, handoffs, and other steps taken during an agent run.