TOOL CALLS ARE EXPENSIVE AND FINITE

Summary from the TLDR AI newsletter

Tool calling is many orders of magnitude more costly than calling a plain old function from code. People should design their agentic systems according to the limit on how many tool calls their agents can effectively make. Using a tool call to add two numbers once probably doesn't matter, but scaling the problem up to 1,000 numbers will require a long wait and may exceed context window limits. Calling a function many times in a loop is one of the most common ways to solve a problem with code.