DESIGNING GOOD TOOLS

RATE LIMITS AND QUOTAS A rate limit caps how often a tool may be used in a given time, such as 10 calls per minute. A quota caps the total amount, such as 1,000 calls per day or 50 dollars per month. Both protect against loops and mistakes. A confused agent that calls a paid search service 4,000 times in an hour could cost real money, and a broken email tool could flood inboxes and get your domain blocked. Limits can be set per tool, per agent, per user, and per run. When a limit is hit, the tool should return a clear message such as "Rate limit reached: 10 emails per minute. Wait 30 seconds and try again," so the agent can wait rather than spin. The limits should also respect the external services behind the tool, which often have their own rate limits.