Remark. Sandbox restrictions and trajectory laws [ftip-004T]

A sandbox restricts the environment through its executor, reset rules, permissions, and evidence. ReAct [yao2023react, Section 2] supplies the action--observation pattern. Software-agent systems surveyed in [wang2024agents, Section 2.3.2] add repositories, compilers, tests, and other digital tools. The combined sandbox interface is a proposed model of these choices.

Two protocols that share prompts but change reset or permission semantics need not induce the same trajectory law.