agent harness — The scaffolding around a model that turns it into a working agent — the loop, the tools it can call, and the rules for when to stop.
AI agent — An AI system that doesn't just answer once but works toward a goal in a loop — taking actions, reading the results, and deciding what to do next.
Why it matters
A coding-AI agentAn AI system that doesn't just answer once but works toward a goal in a loop — taking actions, reading the results, and deciding what to do next.Full definition → interface built on the Agent Client Protocol rather than one vendor's stack lets users run Poolside, Claude Code, Codex, or a local model side by side, with the session (repo, branch, tools, permissions) as the unit of work instead of a chat thread.
