Long-horizon conversational agents require memory that can evolve with dialogue, retrieve information on demand, and remain uncertainty-aware when evidence is insufficient, rather than merely larger storage or context windows. Existing methods store interaction histories as retrievable text, summaries, or vector indices, and retrieve relevant content at query time. Although effective for simple factual queries, this paradigm does not explicitly model how memory writes change state, leaving temporal updates, plan changes, and counterfactual reasoning to query-time inference over retrieved text.

We propose ProgMem, which compiles dialogue events into structured memory programs and checks answers against dialogue evidence. On LoCoMo-10, ProgMem has the highest average F1 with Qwen3-4B, Qwen3-8B, and Qwen3-14B. Its temporal F1 exceeds Mem0 by up to 9.95 points and Zep by at least 12.88 points across these settings. Ablations show gains from route-aware retrieval and two-stage verification. On DialSim, ProgMem improves Answerable and FUQ F1 over Mem0 while using fewer query-time memory tokens. A single-GPU comparison finds higher mean and P95 query latency than Mem0. These results show where state maintenance helps and what it costs at query time.