LLM-based web scraping agents have different proxy requirements than traditional scrapers. A classic scraper retries on failure and moves on. An agent compounds failures — a blocked request means a missed tool call, which means a corrupted reasoning chain, which means a bad output. The proxy layer isn't incidental infrastructure; it's a direct input to agent reliability.
Here is what actually matters when selecting a proxy for agent workloads, and how to evaluate options against those criteria.
Why residential proxies, not datacenter
Datacenter proxies are fast and cheap, but modern anti-bot systems — Cloudflare, Akamai, Datadome — flag datacenter IP ranges at high rates. For a human clicking through a blocked page, this is a mild inconvenience. For an agent making a tool call inside a reasoning loop, it's a silent failure. Residential IPs route through real consumer devices, so they carry the same fingerprint profile as organic traffic. Success rates are materially higher on protected pages. For agent workloads where each request matters, the higher per-GB cost of residential proxies is almost always worth it.
Rotating vs. sticky sessions for agents
This is the most commonly misunderstood tradeoff for agent use cases. Rotating proxies assign a fresh IP per request, which maximizes anonymity and avoids IP-level rate limiting across a long agent run. Sticky sessions hold the same IP for a defined window, which is necessary when the target site uses session-state — login cookies, cart state, multi-step forms. Most agent workflows touch both patterns: research agents need rotation; agents that authenticate and navigate a portal need sticky sessions.
The practical requirement is a proxy provider that supports both modes without separate products or separate billing. You want rotating as the default and the ability to pin a session when your agent's tool call requires continuity.
Protocol and auth model
Agents making HTTP tool calls need proxies that speak HTTP or SOCKS5 with credential-based auth — not IP allowlisting, which breaks in cloud environments where agent compute moves across IP addresses. Username/password auth over standard proxy endpoints is the right model: it