# Levirge Brain vs Hindsight

[Hindsight](https://hindsight.vectorize.io/), from Vectorize, is an
MIT-licensed memory engine for agents (retain, recall, reflect). Brain is
shared memory for teams of agents and people. Both run the same core retrieval
recipe. Hindsight details come from its site and paper, reviewed between Aug
and Oct 2026.

## Where Hindsight is ahead

| Capability | Hindsight | Brain |
| --- | --- | --- |
| Time-aware search | Parses dates out of the query. Stores when a fact happened separately from when it was mentioned. Time is its own retrieval channel. | Ranks fresher documents higher and lists documents by date window. Search takes no time filter; queries aren't date-parsed. |
| Entity graph in retrieval | Spreading activation over entity, causal and temporal links. | Entity graph to browse and query; it doesn't feed search ranking. |
| Belief confidence | Opinions carry a 0–1 confidence that evidence moves. | Facts are active, superseded, disputed or retired. No per-belief score. |
| Deployment and reach | Cloud, embedded, or your own Postgres. 51.4k GitHub stars (per its site, Oct 2026). | Hosted, or on-premise. |

## Both do

- **Hybrid retrieval:** keyword and semantic results fused (RRF), cross-encoder
  rerank, results cut to a token budget.
- **Consolidated summaries** that keep history: the newer fact as current, the
  older one as "previously".
- **Supersede and validity:** a replaced fact is marked invalid from a point in
  time.
- **Near-duplicate merging** with an LLM merge-or-keep check.
- **Isolated stores:** Hindsight calls them banks; Brain calls them vaults.

## Only in Brain

| Capability | Brain | Hindsight |
| --- | --- | --- |
| Team memory | Grant other users access to a vault. | Banks are single-owner. |
| Agent-to-agent handoffs | Durable inbox between agents. | None. |
| Lineage and trust | Facts trace to source documents, with trust tier and origin; runbooks are draft or ratified. | Evidence and provenance; no trust tiers or ratification. |
| Obsidian | Two-way sync. | One-way markdown mount of knowledge pages. |
| Secret redaction | Always on at ingest, every vault. | Opt-in per bank; also covers PII and can block. |
| Work continuity | Sessions, todos and skills next to the memory. | Memory and knowledge pages; no todos or skills. |

## Where each fits

- **Hindsight:** one agent or user that needs strong recall across time, or
  memory embedded in your own app. MIT-licensed, self-hosts in one container.
- **Brain:** several agents and people working from the same memory, with
  access grants, handoffs, and facts traceable to their source.

## Benchmarks

Hindsight reports LongMemEval-S 94.6 and LoCoMo 92.0 on
[its site](https://hindsight.vectorize.io/). Those are its own numbers, scored
by judge models that differ from the baselines it compares against. Brain
hasn't published scores under a third-party harness, so we don't put the two
side by side.

## Method

Hindsight: repo `vectorize-io/hindsight` and paper arXiv:2512.12818 (reviewed
19 Aug 2026), site re-read 25 Sep and 19 Oct 2026. Brain: checked against its
source on 19 Oct 2026. Both projects move fast; check the current docs.