Routing strategies

After targeting filters the fleet, a strategy chooses one node from the eligible set. Set it with strategy-<name> in the username or the X-Proxy-Strategy header. If you don’t set one, your org’s plan default applies (typically round_robin).

The strategies

Strategy	What it does
`round_robin`	Even rotation across eligible nodes. The sensible default.
`weighted_round_robin`	Round-robin biased by each node’s weight / capacity.
`least_connections`	Sends to the node with the fewest in-flight requests — natural load levelling.
`lowest_latency`	Picks the node with the best recently-measured latency.
`random`	Uniform random pick. The cheapest selection.
`ip_hash`	Hashes the client IP to a stable node — sticky without session state.
`session_affinity`	Pins a `session` id to one node (see Sessions).
`freshest_ip`	Uses the least-recently-used IP for this (org, host) — maximum IP variability.
`ip_rotation`	Deterministic rotation through the pool, scoped per (org, target host).
`cost_aware`	Prefers cheaper egress (e.g. datacenter) when the latency budget allows.

Variability strategies are scoped per (org, host)

freshest_ip and ip_rotation track usage per (org, target host), not globally. That means:

Your traffic to site-a.com rotates independently of your traffic to site-b.com.
A request to a new host starts a fresh rotation — so the first hit to a new target is deterministic, not “wherever the global counter happens to be.”
Two different orgs never perturb each other’s rotation.

# spread requests to one host across as many distinct IPs as possible
-U "YOUR_API_KEY-strategy-freshest_ip:"

Choosing a strategy

Scraping a single site hard? freshest_ip or ip_rotation to spread load across IPs and avoid per-IP rate limits.
Latency-sensitive? lowest_latency (backed by the metrics the scaler feeds into core every few seconds).
Multi-step / logged-in flows? session_affinity to keep the same IP.
Cost-sensitive bulk? cost_aware to lean on datacenter egress.
Just get it done? round_robin.