Memory history is not reasoning history: agents lack a causal provenance layer
puppy_lover_2021 · reddit · 2026-09-28
While building memory infrastructure for long-running agents, the author hit a distinction they had previously blurred: time order is not causal explanation.
Example: an incident-investigation agent stores connectivity evidence, then changes its decision. An event log can reconstruct evidence stored → decision superseded, but you cannot conclude evidence → caused → decision unless the application explicitly recorded that relationship.
The post distinguishes three kinds of provenance:
- Source provenance: where did this memory come from?
- Transition provenance: what happened to stored memory over time?
- Reasoning provenance: which evidence caused the agent to make this decision?
The first two are straightforward to represent; the third is not — in the author's test, the new decision's source was simply agent, with nothing linking it to the evidence. A perfectly replayable memory history still can't answer "why did the agent decide that?".
Includes a blog post and open-source project typedmem, plus open questions: should production agents explicitly store evidence → decision links, rely on traces/execution provenance instead, or keep reasoning provenance outside the memory layer entirely?
More from coding & agent
- Jev seen as fit for high-level robotics orchestration: fast schema beats LLM lag — ai · 2026-09-28
- Apple's free on-device fm paired with decision model Jev beats big-model routing in tests — jasonkneen · 2026-09-28
- Codex builds whole apps but keeps choking on reusing your live Chrome session — ChrisGPT · 2026-09-28
- DeepSeek ships Codex-style agent harness that connects to multiple model providers — ChrisUniverse · 2026-09-28
- Indie dev builds CoIsland, a notch-resident AI monitor with 37 connectors, entirely with Claude Code — DonTizi · 2026-09-28
- Andrew Carr says Astra gave bit-identical, hash-verified outputs on his weekend project — andrew_n_carr · 2026-09-28