Why Your Web Scraper's Retry Logic May Be Triggering Permanent Blocks

A software developer has outlined why generic retry logic in web scrapers often worsens blocks rather than resolving them. The core argument is that different failure types — such as HTTP 429 rate limits, 403 hard blocks, and transport-level timeouts — require distinct responses rather than a one-size-fits-all sleep-and-retry approach. For instance, retrying a 403 response repeatedly signals a detectable pattern to the target server, escalating a temporary block into a permanent one. The author recommends classifying failures by type, honoring server-provided retry headers, and tracking per-host request counts to self-impose limits before a block occurs. Recording these thresholds to disk allows subsequent scraper runs to begin with awareness of safe request ceilings for each host.