/refine) reviews trajectory and applies evidence-backed updates to supplemental harness state (packages/coding-agent/src/core/refinement/). Never rewrites the immutable base system prompt. Snapshot mechanism supports rollback. Compaction (packages/coding-agent/src/core/compaction/) trims context (compact, calculateContextTokens, prepareBranchEntries) to stay within model context window.
Related: Compaction, Skills