I got tired of watching coding agents spin up from scratch every single time I sent them a prompt. Cold starts, re-cloning massive monorepos, pasting the previous context into a synthetic prompt block — it worked, but it felt fundamentally wrong for agents that are supposed to think in conversations.
So we shipped persistent sessions for the Critique Coding Agent API. Here's what changed, why the harness matters, and why you should never run a coding agent without a review skill.
The Problem: Agents That Forget
When we first released the Coding Agent API, follow-ups were honest but clunky: every follow-up was a brand-new job. The previous output was replayed as plain text into a fresh sandbox.
It was the right MVP. It billed predictably. It never pretended a dead sandbox was alive.
