What does a 429 error mean and what causes it?

A 429 error, also known as 'Too Many Requests', indicates that the user has sent too many requests in a given amount of time ('rate limiting'). This is a server-side response designed to protect against abuse, denial-of-service attacks, or simply to ensure fair usage of resources. Common causes include exceeding API rate limits, aggressive scraping, or a malfunctioning application making excessive requests.