Core Concepts
Understand the core memory concepts before tuning retrieval or shipping integrations.
Memory is multi-representation
Aletheia stores a memory event in multiple forms: raw text, embedding vector, lexical index terms, and graph relationships. This is why exact terms and paraphrases can both be recovered without scanning full transcripts.
The engine is not just an ANN index. It is a retrieval system that fuses multiple signals into one ranked result list.
Companion memories
Ingest can emit companion records such as facts and summaries. Companion memories compress conversational noise into stable retrieval surfaces, improving recall quality on long sessions.
Companions are linked back to source turns through graph edges so provenance is auditable.
- Fact companions represent stable propositions.
- Summary companions capture compact session gist.
- Derived records never lose linkage to original turns.
Freshness and truth
Temporal ranking and fact supersession prevent stale context from dominating retrieval. If user preferences change, older conflicting facts are demoted or invalidated.
The practical goal is simple: newer truth should win unless the query explicitly asks for historical state.