Context Engineering Moves Into Harnesses

Bigger context windows are not solving the hard part of agent reliability; disciplined context management is.

• –Long contexts introduce poisoning, distraction, confusion, and clashes between tools or instructions.
• –Effective harnesses use loadouts, quarantine, pruning, offloading, and summarization to keep agents focused.
• –The field is shifting from probabilistic prompt work toward deterministic orchestration code.
• –Persistent agents create a new risk: accumulated memories and skills can conflict, decay, or reinforce bad decisions.
• –Developers should treat context resets and strategic forgetting as core reliability mechanisms, not emergency fixes.