Cold starts were the biggest complaint from teams running agents behind user-facing APIs. We rebuilt how Sigil Cloud packages and boots agents to fix it.
What we changed
Agent images are now snapshotted after the SDK initialises, so tool schemas and prompts are already loaded on boot.
Model clients keep warm connection pools per region.
Idle agents scale to a single warm instance instead of zero, at no extra cost on the Team and Scale plans.
Results
Across all Cloud workloads, the median cold start dropped from 1.2 s to 390 ms and p95 from 1.9 s to 480 ms. No redeploy is needed. The change rolled out to every region on July 22.