Thêm tools và function calling cho AI Agents

import json
from decimal import Decimal

SCHEMA = {"type": "function", "name": "shipping_quote",
    "description": "Fictional training shipping estimate, not a purchase.",
    "strict": True, "parameters": {"type": "object", "properties": {
        "zone": {"type": "string", "enum": ["local", "regional"]},
        "weight_kg": {"type": "number"}},
        "required": ["zone", "weight_kg"], "additionalProperties": False}}

def execute_tool(name, raw):
    if name != "shipping_quote":
        raise ValueError("unknown tool")
    args = json.loads(raw)
    if not isinstance(args, dict) or set(args) != {"zone", "weight_kg"}:
        raise ValueError("unexpected arguments")
    zone, weight = args["zone"], args["weight_kg"]
    if zone not in ("local", "regional"):
        raise ValueError("invalid zone")
    if type(weight) not in (int, float) or not 0 < weight <= 100:
        raise ValueError("invalid weight")
    base = Decimal("3") if zone == "local" else Decimal("6")
    amount = base + Decimal(str(weight)) * Decimal("2")
    return {"amount": str(amount.quantize(Decimal("0.01"))),
            "currency": "DEMO", "fictional": True}

if __name__ == "__main__":
    assert execute_tool("shipping_quote", '{"zone":"local","weight_kg":2}')["amount"] == "7.00"
    for raw in ['{"zone":"other","weight_kg":1}',
                '{"zone":"local","weight_kg":true}',
                '{"zone":"local","weight_kg":-1}']:
        try:
            execute_tool("shipping_quote", raw)
        except ValueError:
            continue
        raise AssertionError("invalid input accepted")
    print("shipping checks passed")

python3 shipping.py