Core terminology

The following terms describe how Neotoma structures, stores, and evolves memory state. Each maps to a concrete layer of the deterministic state pipeline.

If you are new to Neotoma, read the terms in this order: Source -> Observation -> Entity snapshot -> Relationship -> Memory graph. Then review the data model walkthrough for end-to-end examples.

Term	Definition
State layer	Neotoma's role: a deterministic, immutable structured memory substrate that other layers read and write.
Entity	Canonical representation of a person, company, or other object with a deterministic ID.
Entity snapshot	Current truth for an entity; computed by merging all observations about that entity.
Observation	Granular fact extracted from source; reducers merge observations into entity snapshots.
Source	Raw data (file, text, URL, or structured JSON) stored with content-addressed deduplication.
Provenance	Origin tracking (source, timestamp, user, interpretation) so every value traces back to its source.
Memory graph	The graph of source, observations, entities, relationships, and events with typed edges.
Reducer	Deterministic function that merges observations into an entity snapshot; same observations always yield the same snapshot.
Relationship	Typed connection between two entities (e.g. SETTLES, REFERS_TO, PART_OF).
Entity type	Classification (e.g. person, company, invoice) that determines the entity schema and resolution rules.
Storing	Uploading and processing source into the memory graph (unstructured or structured).
Retrieving	Querying entities, entity snapshots, observations, and related data from the memory graph.

Where these terms appear

Architecture · deterministic state pipeline and guarantees
MCP reference · actions that operate on entities, observations, and relationships
CLI reference · command-level access to snapshots, observations, and graph operations