Schema lifecycle management for Basic Memory: discover unschemaed notes, infer schemas, create and edit schema definitions, validate notes, and detect drift. Use when working with structured note types (Task, Person, Meeting, etc.) to maintain consistency across the knowledge graph.

Memory Schema Manage structured note types using Basic Memory's Picoschema system. Schemas define what fields a note type should have, making notes uniform, queryable, and validatable. When to Use New note type emerging — you notice several notes share the same structure (meetings, people, decisions) Validation check — confirm existing notes conform to their schema Schema drift — detect fields that notes use but the schema doesn't define (or vice versa) Schema evolution — add/remove/change fields as requirements evolve On demand — user asks to create, check, or manage schemas Picoschema Syntax Reference Schemas are defined in YAML frontmatter using Picoschema — a compact notation for describing note structure. Basic Types Supported types: string , integer , number , boolean . Optional Fields Append ? to the field name: Enums Use (enum) with a list of allowed values: Optional enum: Arrays Use (array) for list fields: Relations Reference other entity types directly: Relations create edges in the knowledge graph, linking notes together. Validation Settings Use strict as the canonical enforcing mode. error is accepted only as a compatibility alias. Complete Example Discovering Unschemaed Notes Look for clusters of notes that share structure but have no schema: 1. Search by type : search notes(query="type:Meeting") — if many notes share a type but no schema/Meeting.md exists, it's a candidate. 2. Infer a schema : Use schema infer to analyze existing notes and generate a suggested schema: The threshold (0.0–1.0) controls how common a field must be to be included. Default is usually fine; lower it to catch rarer fields. 3. Review the suggestion — the inferred schema shows field names, types, and frequency. Decide which fields to keep, make optional, or drop. Creating a Schema Write the schema note to schema/<EntityName : Key Principles Schema notes live in schema/ — one note per entity type note type="schema" marks it as a schema definition entity: Meeting in metadata names the type it applies to version: 1 in metadata — increment when making breaking changes settings.validation: warn is recommended to start — it logs issues without blocking writes Validating Notes Check how well existing notes conform to their schema: Important: schema validate checks for schema fields as observation categories in the note body — e.g., a status field expects [status] active as an observation. Fields stored only in frontmatter metadata won't satisfy validation. To pass cleanly, include schema fields as both frontmatter values (for metadata search) and observations (for schema validation). Validation reports: Missing required fields — the note lacks a field the schema requires (as an observation category) Unknown fields — the note has fields the schema doesn't define Type mismatches — a field value doesn't match the expected type Invalid enum values — a value isn't in the allowed set Handling Validation Results warn mode : Review warnings periodically. Fix notes that are clearly wrong; add optional fields to the schema for legitimate new patterns. strict mode : Use where conformance matters (e.g., automated pipelines consuming notes). Detecting Drift Over time, notes evolve and schemas lag behind. Use schema diff to find divergence: Diff reports: Fields in notes but not in schema — candidates for adding to the schema (as optional) Schema fields rarely used — consider making optional or removing Type inconsistencies — fields used as different types across notes Schema Evolution When note structure changes: 1. Run diff to see current state: schema diff(noteType="Meeting") 2. Update the schema note via edit note : 3. Add/remove/modify fields in the schema: block 4. Re validate to confirm existing notes still pass: schema validate(noteType="Meeting") 5. Fix outliers — update notes that don't conform to the new schema Evolution Guidelines Additive changes (new optional fields) are safe — no version bump needed Breaking changes (new required fields, removed fields, type changes) should bump version Prefer optional over required — most fields should be optional to start Don't over constrain — schemas should describe common structure, not enforce rigid templates Schema as documentation — even if validation is set to warn , the schema serves as living documentation for what notes of that type should contain Workflow Summary

memory-schema