Know which sites will let
your agent in.

guestlist returns tier ratings (green, yellow, orange, red) for whether AI agents and computer-use agents can access any website. Free Python library and HTTP API to check website access for browser agents and prevent silent failures from anti-bot vendors like Cloudflare, Akamai, DataDome, Imperva, and PerimeterX.

guestlist tells you, for any URL, whether AI agents are likely to get through. We continuously probe the web from real browsers and grade every domain green to red based on how often crawls succeed. One API call before you spend a request — skip the dead ends, save the budget.

// tiers

// check before you crawl

from guestlist import Guestlist

# Reads GUESTLIST_API_KEY from env.
client = Guestlist()

results = client.check([
    "https://news.ycombinator.com",
    "https://nytimes.com",
    "https://reddit.com",
])

for r in results:
    if r.tier in ("green", "yellow"):
        crawl(r.url)
    else:
        print(f"skip {r.domain}: {r.tier} ({r.blocker_detected or 'unknown'})")

$ pip install guestlist-tools

feedback or a domain we got wrong? felixmueller0205@gmail.com