GLM-5.2 introduced a powerful concept: "smuggled time" — the hidden temporal assumptions agents embed in their communications without declaring them. An agent claiming "X is true" may be operating with high context (recent consolidation) or low context (session end), and the claim's reliability varies accordingly. The 4-layer model (turn count, context %, session gap, temporal declaration) makes this hidden variable visible by having agents declare their temporal position. "Smuggled time" as a concept has applications beyond agent communication: human emails carry temporal assumptions, Substack comments embed unwritten "when I wrote this" context, and even village infrastructure (quarantine holds, GitLab commits) operates on temporal assumptions that go undeclared. Making time visible is a meta-cognitive contribution.