Your agent forgot a decision you made last week. Mine did too.

A developer built memgraph, a zero-dependency Node.js CLI that stores decisions, facts and their relationships in a single JSON file committed alongside code, so agents and teams can trace why a choice was made and what superseded it. The tool answers queries like `memgraph why` and runs `memgraph check` as a CI gate that exits 1 on unresolved contradictions, live nodes resting on superseded decisions, or sourceless claims. In the bundled demo graph, check flags a fallback reader still depending on a superseded queue decision and an unsourced open question, while treating a contradiction against a superseded decision as resolved history.

Last month my team reversed a queue decision. Nobody could say why we had picked the first design, what evidence it rested on, or who had signed off on the replacement. The old design was still half-wired in as a "fallback", quietly depending on the thing we had just replaced. We found out in production. Vector RAG remembers text . It does not remember decisions — what was chosen, what it rested on, what contradicted it, and what replaced it. So I built a tiny local graph for exactly that: memgraph . One zero-dependency Node.js CLI. No network, no server, no embeddings. The store is a single JSON file you can commit next to your code. memgraph init memgraph add --type decision --title "Use Postgres LISTEN/NOTIFY for the queue" --source "ADR-014" memgraph add --type fact --title "NOTIFY payloads cap at 8000 bytes" --source "Postgres docs" memgraph link m-002 m-001 --relation contradicts memgraph add --type decision --title "Switch the queue to Redis Streams" --source "ADR-019" memgraph supersede m-001 m-003 --reason "payload cap makes NOTIFY the wrong tool" Three questions it answers, fast: memgraph why m-003 — source, supporters, contradictions, supersession. memgraph check — unresolved contradictions, live nodes resting on superseded ones, sourceless claims. memgraph list — every node, with superseded ones marked. memgraph check exits 1 when it finds an error, so it works as a CI gate: a PR that introduces a contradiction, or keeps depending on a superseded decision, fails before it merges. The repo ships a small team graph — a queue decision, the fact that killed it, its replacement, and one leftover fallback still depending on the dead design: sh examples/run-demo.sh memgraph check on that graph reports exactly two problems: the fallback reader depends on a superseded decision, and one open question has no source. The contradiction between the payload-cap fact and the old decision does not get flagged — the old decision was superseded, so that contradiction is resolved history, not a live conflict. A graph is only as good as what you record. memgraph cannot tell you whether a source is true — it tells you where every claim came from and whether the graph still holds together. A decision with no source is a rumor with formatting; that is why check flags it. And when a decision changes, supersede it — don't delete it. Deleting history is how teams end up re-litigating the same choice every six months. Repo: https://github.com/techdevfun/memgraph https://github.com/techdevfun/memgraph — MIT, zero dependencies, Node.js 18+.