A strict schema that isn't

This tool was marked strict so its inputs would always validate, but malformed arguments still reach the handler and the API never complained about the definition.

tools = [{
    "name": "book_flight",
    "description": "Book a flight.",
    "input_schema": {
        "type": "object",
        "properties": {
            "destination": {"type": "string"},
            "passengers": {"type": "integer"},
        },
        "required": ["destination", "passengers"],
    },
}]

response = client.messages.create(
    model="claude-opus-5",
    max_tokens=16000,
    tools=tools,
    tool_choice={"type": "auto", "strict": True},
    messages=messages,
)