Elpis is a terminal environment for coding agents, built on OpenAI's Codex CLI. The core problem: long agent sessions bury useful state under the history of how the agent got there. Every request pays for all of it. Elpis separates working context from durable evidence. After each turn, a meaning-aware pruner (Ace) evicts completed tool outputs, resolved dead ends, and low-signal history from the live context to disk. The next request starts lean.