Memory MCP Server

An enhanced fork of the official Model Context Protocol memory server with advanced features for hierarchical nesting, intelligent compression, semantic search, graph algorithms, archiving, advanced search, and multi-format import/export.

Enterprise-grade knowledge graph with 241 tools including hierarchical organization, semantic search with embeddings, graph traversal algorithms, duplicate detection, smart archiving, project scoping, temporal knowledge graph, semantic forget, agent diary, entity bitemporal validity (η.4.4), optimistic concurrency control (η.5.5.c), role-based access control (η.6.1), W3C Linked Data exports (Turtle / JSON-LD / RDF/XML — η.5.4), PII redaction on export (η.6.3), procedural memory (3B.4), active retrieval (3B.5), causal reasoning (3B.6), world model (3B.7), do_not_remember exclusions, decision rationale (ADR memory + markdown dual-write), structured project context (facts / conventions / commands / glossary), heuristic guidelines, tool affordance + ToolCallObserver pipeline (with MCP shim), observation dedup, spell correction (memoryjs v2.1.0 — Phase 16), n-ary event memory, reconstructive (Cue–Tag–Content) memory with snapshot persistence, relation consolidation, agent reflections, and a graph-connectivity hybrid-search channel with evidence-path explanations (memoryjs v3.0.0 — v12.7.0) for long-term memory management.

Features

Core Memory Capabilities

Knowledge Graph Storage: Entity-Relation-Observation model for structured memory
Persistent Memory: Information persists across chat sessions with JSONL or SQLite storage
Dual Storage Backends: JSONL (human-readable) or SQLite with better-sqlite3 (3-10x faster, FTS5 search)
Full CRUD Operations: Create, read, update, delete entities and relations
Flexible Search: Text-based, fuzzy, boolean, semantic, and TF-IDF ranked search

Advanced Features

Category	Tools	Description
Hierarchical Nesting	9	Parent-child relationships for organizing tree structures
Graph Algorithms	4	Path finding, connected components, centrality metrics
Intelligent Search	3	Hybrid multi-layer search with query analysis and reflection
Semantic Search	3	Embedding-based similarity search with OpenAI or local models
Memory Compression	4	Intelligent duplicate detection and merging with similarity scoring
Advanced Search	7	TF-IDF ranking, boolean queries, fuzzy matching, auto-select
Observation Normalization	1	Coreference resolution and temporal anchoring
Tag Management	6	Tags, bulk operations, importance scores
Tag Aliases	5	Tag synonym/alias management
Saved Searches	5	Store and execute frequent queries
Import/Export	2	7 export formats (incl. W3C Linked Data: Turtle / JSON-LD / RDF/XML) with brotli + PII redaction; 3 import formats
Graph Analytics	2	Statistics, validation, integrity checks
Ref Index	4	Cross-session symbolic reference registration and resolution
Artifacts	3	Named versioned content blobs attached to entities
Temporal Search	1	Time-window filtered search across the knowledge graph
Distillation	1	Configure automated observation distillation pipelines
Freshness	5	Staleness tracking, expiry detection, and freshness reporting
LLM Query	1	Natural-language question answering over the graph
Governance	4	Transactional audit trail, history, and rollback
Role Profiles	2	Per-agent role assignment and profile listing
Entropy	2	Entropy-based noise filtering and information density scoring
Consolidation	3	Background memory consolidation scheduling and control
Formatter	1	Salience-budget-aware context formatting
Collaborative	1	Multi-agent context synthesis
Failure Handling	2	Session failure distillation and graceful session end
Cognitive Load	2	Working-memory load analysis and adaptive reduction
Dream Engine	3	Background memory maintenance: 8-phase sleep-cycle consolidation
Project Scoping	1	List and filter entities by project
Memory Versioning	2	Entity version chains and per-entity version history
Semantic Forget	1	Two-tier deletion: exact match → semantic similarity fallback
Profiles	2	User/agent profile get and update
Temporal KG	3	Temporal relation invalidation, time-travel queries, relation timeline
Ingestion	1	Format-agnostic conversation/document ingestion pipeline
Agent Diary	2	Per-agent persistent journal write and read
Session & Working Memory	9	Session lifecycle, working memory CRUD, TTL, promotion, context wake-up (Phase 14)
Auto-Enhancement	3	Auto-link entity mentions, fact extraction, contradiction detection (Phase 14)
Context Compression	1	N-gram text abbreviation with legend for token savings (Phase 14)
Consolidation Pipeline	3	Session consolidation, pattern detection, entity summarization (Phase 14)
Decay & Salience	5	Time-based decay, importance scoring, weak memory cleanup, reinforcement (Phase 14)
Multi-Agent	5	Agent registration, cross-agent search, visibility, conflict resolution (Phase 14)
Observability	4	D3.js graph visualization, transcript splitting, query cost estimation (Phase 14)
Dedup	1	Priority-based smart deduplication (Phase 14)
Entity Bitemporal	5	Time-travel queries: invalidate entities/observations, entity_as_of, timelines (Phase 15 / η.4.4)
Optimistic Concurrency	1	`update_entity` with `expectedVersion` → `VersionConflictError` on stale (Phase 15 / η.5.5.c)
RBAC	4	Role-based access control: assign/revoke/check/list reader/writer/admin/owner permissions (Phase 15 / η.6.1)
Procedural Memory	5	Executable how-to sequences with EWMA-refined success rate (Phase 15 / 3B.4)
Active Retrieval	1	Iterative query rewriting until coverage threshold met (Phase 15 / 3B.5)
Causal Reasoning	4	Chain discovery, counterfactual queries, cycle detection (Phase 15 / 3B.6)
World Model	3	Graph snapshots, fact validation, outcome prediction (Phase 15 / 3B.7)

Comparison with Official Memory Server

Feature	Official	Enhanced (This Fork)
Entity/Relation/Observation Management	✅	✅
Basic Search	✅	✅
Hierarchical Nesting	❌	✅ Parent-child trees
Graph Algorithms	❌	✅ Path finding, centrality
Semantic Search	❌	✅ Embedding-based similarity
Memory Compression	❌	✅ Duplicate detection
Brotli Compression	❌	✅ Backups, exports, responses
Smart Archiving	❌	✅ Criteria-based
Advanced Search	❌	✅ TF-IDF + Boolean + Fuzzy
SQLite Backend	❌	✅ better-sqlite3 (3-10x faster)
Full-Text Search	❌	✅ FTS5 with BM25 ranking
Timestamps	❌	✅ createdAt + lastModified
Import/Export Formats	❌	✅ 7 export / 3 import
Input Validation	❌	✅ Zod schemas
Backup & Restore	❌	✅ Compressed snapshots
Intelligent Search	❌	✅ Hybrid + Query Analysis + Reflection
Observation Normalization	❌	✅ Coreference resolution + temporal anchoring
Total Tools	11	160
Code Structure	Monolithic	Modular (5 src files in this repo; core graph in `@danielsimonjr/memoryjs`)

Quick Start

1. Install from NPM

npm install -g @danielsimonjr/memory-mcp

Or use with npx (no installation required):

npx @danielsimonjr/memory-mcp

2. Configure Claude Desktop

Add to claude_desktop_config.json:

Using NPM Global Install:

{
  "mcpServers": {
    "memory": {
      "command": "mcp-server-memory"
    }
  }
}

Using NPX:

{
  "mcpServers": {
    "memory": {
      "command": "npx",
      "args": ["-y", "@danielsimonjr/memory-mcp"]
    }
  }
}

3. Restart Claude Desktop

Restart Claude Desktop to load the enhanced memory server.

4. Start Using

Tell Claude:

Please remember that I prefer TypeScript over JavaScript.
Tag this as "preferences" with importance 8.
Create a parent entity called "Development Preferences" and nest this under it.

Installation

Local Build

# Clone repository
git clone https://github.com/danielsimonjr/memory-mcp.git
cd memory-mcp

# Install and build
npm install
npm run build

# Run tests (791 tests, ~85% statement coverage)
npm test

# Type check
npm run typecheck

Claude Desktop Configuration

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (Mac) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "memory": {
      "command": "node",
      "args": ["<PATH_TO>/memory-mcp/dist/index.js"],
      "env": {
        "MEMORY_FILE_PATH": "<PATH_TO>/memory.jsonl"
      }
    }
  }
}

VS Code

Add to .vscode/mcp.json:

{
  "servers": {
    "memory": {
      "command": "node",
      "args": ["/path/to/memory-mcp/dist/index.js"]
    }
  }
}

Core Concepts

Entities

Primary nodes in the knowledge graph.

interface Entity {
  name: string;           // Unique identifier
  entityType: string;     // Classification
  observations: string[]; // Facts about the entity
  parentId?: string;      // Parent entity name for hierarchical nesting
  tags?: string[];        // Lowercase tags for categorization
  importance?: number;    // 0-10 scale for prioritization
  createdAt?: string;     // ISO 8601 timestamp
  lastModified?: string;  // ISO 8601 timestamp
}

Relations

Directed connections between entities.

interface Relation {
  from: string;           // Source entity name
  to: string;             // Target entity name
  relationType: string;   // Relationship type (active voice)
  createdAt?: string;     // ISO 8601 timestamp
  lastModified?: string;  // ISO 8601 timestamp
}

Observations

Discrete facts about entities. Each observation should be atomic and independently manageable.

API Reference

Complete Tool List (241 Tools)

Tool count: 241 tools across 65 categories. The newest tools are documented at the end under the Phase 15, Phase 16 (memoryjs v2.1.0), v12.3.2 / v12.5.0, and v12.7.0 (memoryjs v3.0.0) sections. For full per-tool schemas see docs/architecture/API.md or src/server/toolDefinitions.ts.

Entity Operations (4 tools)

Tool	Description
`create_entities`	Create multiple new entities
`delete_entities`	Remove entities and their relations
`read_graph`	Read entire knowledge graph
`open_nodes`	Retrieve specific nodes by name

Relation Operations (2 tools)

Tool	Description
`create_relations`	Create relations between entities
`delete_relations`	Remove specific relations

Observation Management (3 tools)

Tool	Description
`add_observations`	Add observations to entities
`delete_observations`	Remove specific observations
`normalize_observations`	Normalize observations (resolve pronouns, anchor dates)

Search (7 tools)

Tool	Description
`search_nodes`	Search with filters (tags, importance)
`search_by_date_range`	Filter by date range
`search_nodes_ranked`	TF-IDF relevance ranking
`boolean_search`	Boolean queries (AND/OR/NOT)
`fuzzy_search`	Typo-tolerant search
`get_search_suggestions`	"Did you mean?" suggestions
`search_auto`	Auto-select best search method

Intelligent Search (3 tools)

Tool	Description
`hybrid_search`	Multi-layer search combining semantic, lexical, and symbolic signals
`analyze_query`	Extract entities, temporal references, and classify query complexity
`smart_search`	Reflection-based iterative search until results meet adequacy threshold

Semantic Search (3 tools)

Tool	Description
`semantic_search`	Search by semantic similarity using embeddings
`find_similar_entities`	Find entities similar to a reference entity
`index_embeddings`	Build or rebuild the semantic search index

Saved Searches (5 tools)

Tool	Description
`save_search`	Save search query for reuse
`execute_saved_search`	Execute a saved search
`list_saved_searches`	List all saved searches
`delete_saved_search`	Delete a saved search
`update_saved_search`	Update saved search parameters

Tag Management (6 tools)

Tool	Description
`add_tags`	Add tags to an entity
`remove_tags`	Remove tags from an entity
`set_importance`	Set entity importance (0-10)
`add_tags_to_multiple_entities`	Bulk tag operation
`replace_tag`	Replace tag globally
`merge_tags`	Merge two tags into one

Tag Aliases (5 tools)

Tool	Description
`add_tag_alias`	Create tag synonym
`list_tag_aliases`	List all aliases
`remove_tag_alias`	Remove an alias
`get_aliases_for_tag`	Get aliases for canonical tag
`resolve_tag`	Resolve alias to canonical form

Hierarchical Nesting (9 tools)

Tool	Description
`set_entity_parent`	Set/remove parent relationship
`get_children`	Get immediate children
`get_parent`	Get parent entity
`get_ancestors`	Get all ancestors (parent chain)
`get_descendants`	Get all descendants (recursive)
`get_subtree`	Get entity + descendants with relations
`get_root_entities`	Get entities with no parent
`get_entity_depth`	Get depth in hierarchy
`move_entity`	Move entity to new parent

Graph Algorithms (4 tools)

Tool	Description
`find_shortest_path`	Shortest path between entities (BFS)
`find_all_paths`	All paths with max depth limit
`get_connected_components`	Detect isolated subgraphs
`get_centrality`	Calculate centrality metrics (degree, betweenness, PageRank)

Graph Analytics (2 tools)

Tool	Description
`get_graph_stats`	Comprehensive graph statistics
`validate_graph`	Validate graph integrity

Compression & Archiving (4 tools)

Tool	Description
`find_duplicates`	Find similar entities by threshold
`merge_entities`	Merge multiple entities into one
`compress_graph`	Auto compression with dry-run
`archive_entities`	Archive by age, importance, or tags

Import & Export (2 tools)

Tool	Description
`export_graph`	Export in 7 formats (JSON, CSV, GraphML, GEXF, DOT, Markdown, Mermaid) with compression
`import_graph`	Import from JSON/CSV/GraphML with merge strategies

Ref Index (4 tools)

Tool	Description
`register_ref`	Register a symbolic reference pointing to an entity
`resolve_ref`	Resolve a symbolic reference to its target entity
`deregister_ref`	Remove a registered symbolic reference
`list_refs`	List all registered symbolic references

Artifacts (3 tools)

Tool	Description
`create_artifact`	Create a named versioned content blob attached to an entity
`get_artifact`	Retrieve an artifact by name and optional version
`list_artifacts`	List all artifacts, optionally filtered by entity

Temporal Search (1 tool)

Tool	Description
`search_by_time`	Search entities and observations within a time window

Distillation (1 tool)

Tool	Description
`configure_distillation`	Configure automated observation distillation pipelines

Freshness (5 tools)

Tool	Description
`check_freshness`	Check freshness status of a specific entity
`get_stale_entities`	List entities that have exceeded their staleness threshold
`get_expired_entities`	List entities past their explicit expiry date
`refresh_entity`	Reset the freshness timestamp on an entity
`freshness_report`	Generate a full freshness report across the graph

LLM Query (1 tool)

Tool	Description
`query_natural_language`	Answer natural-language questions over the knowledge graph

Governance (4 tools)

Tool	Description
`governance_transaction`	Execute a governed, audited graph transaction
`audit_query`	Query the audit log with filters
`audit_history`	Retrieve full audit history for an entity
`rollback_operation`	Roll back a previously recorded operation

Role Profiles (2 tools)

Tool	Description
`set_agent_role`	Assign a role profile to the current agent context
`list_role_profiles`	List all available agent role profiles

Entropy (2 tools)

Tool	Description
`enable_entropy_filter`	Enable entropy-based noise filtering for search results
`compute_entropy`	Compute information-density entropy score for an entity

Consolidation (3 tools)

Tool	Description
`start_consolidation`	Start the background memory consolidation service
`stop_consolidation`	Stop the background memory consolidation service
`run_consolidation_now`	Trigger an immediate consolidation pass

Formatter (1 tool)

Tool	Description
`format_with_salience_budget`	Format context output respecting a token salience budget

Collaborative (1 tool)

Tool	Description
`synthesize_collaborative_context`	Synthesize a unified context view from multiple agent memory spaces

Failure Handling (2 tools)

Tool	Description
`distill_failure`	Distill and store key observations from a failed session
`end_session`	Gracefully end a session and persist in-flight state

Cognitive Load (2 tools)

Tool	Description
`analyze_cognitive_load`	Analyze working-memory load in the current context
`adaptive_reduce_memories`	Adaptively reduce memory set to fit cognitive load target

Project Scoping (1 tool)

Tool	Description
`list_projects`	List all project IDs present in the graph and filter entities by project

Memory Versioning (2 tools)

Tool	Description
`get_entity_versions`	Retrieve all versions of a versioned entity by name
`get_version_chain`	Get the full version chain from root to latest for an entity

Semantic Forget (1 tool)

Tool	Description
`forget_memory`	Delete an entity by exact name, falling back to semantic similarity if no exact match found

Profiles (2 tools)

Tool	Description
`get_profile`	Retrieve a user or agent profile entity
`update_profile`	Update observations and metadata on a profile entity

Temporal KG (3 tools)

Tool	Description
`invalidate_relation`	Mark a relation as ended by setting its temporal validity end date
`query_as_of`	Retrieve all relations for an entity that were valid at a given point in time
`timeline`	Return a chronological list of relation events for an entity

Ingestion (1 tool)

Tool	Description
`ingest`	Ingest a conversation, document, or free-form text into the knowledge graph

Agent Diary (2 tools)

Tool	Description
`diary_write`	Append an entry to the agent's persistent diary
`diary_read`	Read diary entries for an agent, optionally filtered by date range

Entity Bitemporal Validity (5 tools) — Phase 15 / memoryjs η.4.4

Tool	Description
`invalidate_entity`	Stamp `validUntil` on an entity (idempotent; entity remains queryable for past timestamps via `entity_as_of`)
`entity_as_of`	Time-travel query: returns entity state at a given ISO 8601 timestamp, or `null` if invalidated then
`entity_timeline`	All temporal versions of an entity in chronological order; integrates the v1.8 supersession chain
`invalidate_observation`	Per-observation invalidation via parallel `observationMeta[]` entry on the entity
`observations_as_of`	Filter observations valid at a given timestamp; observations without meta are treated as unbounded

Optimistic Concurrency Control (1 tool) — Phase 15 / memoryjs η.5.5.c

Tool	Description
`update_entity`	Update an entity with optional `expectedVersion`; throws `VersionConflictError` on stale version. OCC-guarded writes auto-increment `version`. Omit `expectedVersion` for legacy last-write-wins.

RBAC (4 tools) — Phase 15 / memoryjs η.6.1

Tool	Description
`rbac_assign_role`	Grant `reader` / `writer` / `admin` / `owner` (or custom) role to an agent; optional `resourceType`, `scope` prefix, `validFrom` / `validUntil` window
`rbac_revoke_role`	Remove a specific role assignment matched by `agentId + role + resourceType`
`rbac_check_permission`	Check whether an agent can perform `read` / `write` / `delete` / `manage` on a resource type; falls back to `defaultRole=reader` for unassigned agents
`rbac_list_assignments`	List all role assignments for an agent; optional `activeOnly` filter

Procedural Memory (5 tools) — Phase 15 / memoryjs 3B.4

Tool	Description
`add_procedure`	Persist an executable how-to sequence: 1-indexed steps with optional fallback chains and free-form trigger phrases
`get_procedure`	Load a procedure by id
`match_procedure`	Token-overlap match a context description against stored procedures; returns ranked Jaccard-like scores
`refine_procedure`	Apply caller feedback after execution; updates `successRate` via EWMA (α=0.2)
`get_procedure_step`	Load step by 1-indexed `order`, or get the next step relative to `currentOrder`

Active Retrieval (1 tool) — Phase 15 / memoryjs 3B.5

Tool	Description
`adaptive_retrieve`	Iterative query-rewriting retrieval (search → score coverage → rewrite); stops early when `coverage ≥ minCoverage`. Pure symbolic — no LLM provider required.

Causal Reasoning (4 tools) — Phase 15 / memoryjs 3B.6

Tool	Description
`find_causes`	Causal chains ending at the named effect; sorted by product-of-edge causalStrength
`find_effects`	Symmetric counterpart starting at the named cause
`counterfactual_query`	"If we remove edge (removeFrom → removeTo), is `predict` still reachable from `seed`?" Returns surviving chains. Pure: does not mutate the graph.
`detect_causal_cycles`	Detect cycles in the causal subgraph rooted at `seed`

World Model (3 tools) — Phase 15 / memoryjs 3B.7

Tool	Description
`get_world_state`	Capture a fresh snapshot of the live graph (capped at 1000 entities; over-cap prefers high-importance)
`validate_fact_against_world`	Validate a candidate observation against a target entity via `MemoryValidator.validateConsistency`. Returns `{result: null, reason: 'embedding_provider_unavailable'}` when the local embedding provider is selected without `@xenova/transformers` installed.
`predict_outcome`	Predict downstream effects of an action by walking the causal subgraph (delegates to `find_effects`)

Phase 15 enhancements to existing tools

export_graph — Now accepts format: 'turtle' | 'rdf-xml' | 'json-ld' for W3C Linked Data exports (memoryjs η.5.4) and redactPii: true to scrub PII (email / SSN / credit-card / phone / IPv4) from observations using the η.6.3 PiiRedactor.
create_entities — Now accepts v1.6 freshness fields (ttl, confidence), v1.8 project scope (projectId), and η.4.4 bitemporal fields (validFrom, validUntil, observationMeta) per entity.
set_memory_visibility — Auto-promotes plain entities to AgentEntity (stamps agentId / memoryType / confidence) instead of silently returning null. Supports η.5.5.b extensions (allowedRoles, visibleFrom, visibleUntil).

Tool Affordance (11 tools) — Phase 16 / memoryjs v2.1.0

Tool	Description
`record_tool_outcome`	Record a tool call outcome (success/failure) into affordance stats
`get_tool_affordance_stats`	Per-tool success-rate and usage statistics
`suggest_tool`	Suggest the best tool for a task based on recorded affordances
`list_tool_affordances`	List all recorded tool affordances
`remove_tool_affordance`	Remove one tool's affordance record
`observe_tool_start`	`ToolCallObserver` lifecycle: mark a tool call started
`observe_tool_complete`	Mark an observed tool call completed successfully
`observe_tool_error`	Mark an observed tool call failed
`observe_tool_partial`	Mark an observed tool call partially successful
`observe_tool_cancel`	Cancel an in-flight tool observation
`tool_observer_in_flight_count`	Count of currently in-flight observed tool calls

Heuristic Guidelines (10 tools) — Phase 16 / memoryjs v2.1.0

Tool	Description
`add_heuristic`	Store a heuristic guideline ("when X, prefer Y")
`get_heuristic`	Fetch one heuristic by id
`list_heuristics`	List stored heuristics
`heuristic_count`	Count of stored heuristics
`match_heuristics`	Heuristics matching a context string
`reinforce_heuristic`	Strengthen a heuristic after successful application
`record_heuristic_contradiction`	Record evidence contradicting a heuristic
`detect_heuristic_conflicts`	Detect mutually contradictory heuristics
`remove_heuristic`	Remove one heuristic
`clear_heuristics`	Remove all heuristics

Project Context (12 tools) — Phase 16 / memoryjs v2.1.0

Tool	Description
`upsert_project_context`	Create/replace a project's structured context record
`get_project_context`	Fetch a project's context record
`append_project_fact`	Append a fact to a project context
`append_project_convention`	Append a coding/workflow convention
`append_project_command`	Append a named command (e.g. build/test invocations)
`append_project_glossary_term`	Append a glossary term + definition
`remove_project_fact`	Remove a fact by index/value
`remove_project_convention`	Remove a convention
`remove_project_command`	Remove a command
`remove_project_glossary_term`	Remove a glossary term
`clear_project_context`	Delete a project's context record
`format_project_context_for_llm`	Render the context as LLM-ready markdown

Decision Rationale (10 tools) — Phase 16 / memoryjs v2.1.0

Tool	Description
`propose_decision`	Record a proposed decision with rationale
`accept_decision`	Mark a decision accepted
`reject_decision`	Mark a decision rejected
`supersede_decision`	Supersede a decision with a newer one
`find_decisions_by_context`	Decisions matching a context string
`get_decision_chain`	Follow a decision's supersession chain
`list_decisions`	List decisions (filterable by status)
`get_decision`	Fetch one decision by id
`export_decision_as_adr_markdown`	Render a decision as ADR markdown
`parse_adr_markdown`	Parse ADR markdown back into a decision record

Exclusion / `do_not_remember` (5 tools) — Phase 16 / memoryjs v2.1.0

Tool	Description
`add_exclusion_rule`	Add a rule for content that must not be remembered
`list_exclusion_rules`	List exclusion rules
`remove_exclusion_rule`	Remove one exclusion rule
`check_exclusion`	Check whether a text would be excluded
`find_matching_memories_for_rule`	Existing memories matching an exclusion rule

Observation Dedup (2 tools) — Phase 16 / memoryjs v2.1.0

Tool	Description
`find_duplicate_observations`	Exact duplicate observations across entities
`find_jaccard_duplicate_observations`	Near-duplicates via Jaccard token similarity

Spell Correction (3 tools) — Phase 16 / memoryjs v2.1.0

Tool	Description
`spell_suggest`	"Did you mean?" suggestions for a query term
`spell_rebuild_vocabulary`	Rebuild the spell-check vocabulary from the graph
`spell_vocabulary_size`	Current vocabulary size

Active Project Scope (2 tools) — v12.3.2

Tool	Description
`set_project_scope`	Set the server's active project-scope filter (per-session mutable state)
`get_project_scope`	Get the active project scope (`{ projectId }`, null when unscoped)

Engineering / Diagnostics (10 tools) — v12.5.0

Tool	Description
`diag`	Server + storage diagnostic snapshot
`health`	Quick health check
`check_graph`	Graph integrity check
`reindex`	Rebuild search indexes
`cache_stats`	Stats for the global search caches
`cache_clear`	Bust all global search caches
`graph_size`	Entity/relation/observation counts + on-disk footprint
`inspect_entity`	Verbose single-entity snapshot (observations, relations, hierarchy)
`hierarchy_tree`	Hierarchy as nested JSON
`entity_neighbors`	Incoming/outgoing relations + degree counts for one entity

Event Memory (5 tools) — v12.7.0 / memoryjs v3.0.0

Tool	Description
`record_event`	Reify an action as an event hub entity with role-typed relations (`actor_of` / `targeted` / `occurred_in` / `participant_in`) and optional `flow:<key>` grouping
`get_event`	Load one event with its resolved role endpoints
`query_events`	Query by actor / target / action / flowKey / time range, chronologically ordered
`get_event_flow`	Full timeline of a named flow (e.g. a release or incident)
`who_did_what`	"Who did what (to target / in context / within range)?" join over events

Reconstructive Memory (5 tools) — v12.7.0 / memoryjs v3.0.0

Tool	Description
`ingest_dialogue`	Distill dialogue turns into the Cue–Tag–Content associative graph (also persisted into the live knowledge graph)
`reconstruct_memory`	Answer a query via active multi-step traversal; returns evidence + trajectory
`reconstructive_memory_stats`	CTC graph size statistics
`save_reconstructive_memory`	Serialize the CTC graph to a `<basename>-reconstructive.json` sidecar
`load_reconstructive_memory`	Restore the CTC graph from the sidecar (survives restarts)

Relation Consolidation (2 tools) — v12.7.0 / memoryjs v3.0.0

Tool	Description
`analyze_relation_duplicates`	Dry-run the three-tier relation janitor: spelling variants, inverse duplicates, semantic duplicates (with embeddings)
`consolidate_relations`	Apply tier 1+2 merges (`apply: true`) or dry-run (default)

Agent Reflection (4 tools) — v12.7.0 / memoryjs v3.0.0

Tool	Description
`create_reflection`	Persist an evidence-backed generalized lesson (scope: session / project / global)
`list_reflections`	List reflections, filterable by scope / source / confidence
`get_relevant_reflections`	Reflections relevant to a session (sourceSessionId + evidence overlap)
`archive_reflection`	Soft-delete a reflection out of default listings

v12.7.0 enhancements to existing tools

hybrid_search — Now accepts memoryjs v3's additive options: graphWeight (graph-connectivity channel via normalized PageRank), expandNeighbors (one-hop expansion of top results with damped scores), explain (annotate results with evidence paths from query anchors), and lookFor (rank expansion neighbors by a free-text connection description).

Configuration

Environment Variables

Variable	Description	Default
`MEMORY_FILE_PATH`	Path to storage file	`memory.jsonl` (current directory)
`MEMORY_STORAGE_TYPE`	Storage backend: `jsonl` or `sqlite`	`jsonl`
`MEMORY_EMBEDDING_PROVIDER`	Embedding provider: `openai`, `local`, `llamacpp`, or `none`	`none`
`MEMORY_OPENAI_API_KEY`	OpenAI API key (required if provider is `openai`)	-
`MEMORY_EMBEDDING_MODEL`	Embedding model to use	`text-embedding-3-small` (OpenAI) / `Xenova/all-MiniLM-L6-v2` (local) / `llamacpp-local` (llamacpp)
`MEMORY_EMBEDDING_BASE_URL`	Base URL of a local `llama-server` (used when provider is `llamacpp`)	`http://127.0.0.1:8080`
`MEMORY_AUTO_INDEX_EMBEDDINGS`	Auto-index entities on creation	`false`

Storage Backends

Feature	JSONL (Default)	SQLite (better-sqlite3)
Format	Human-readable text	Native binary database
Transactions	Basic	Full ACID with WAL mode
Full-Text Search	Basic	FTS5 with BM25 ranking
Performance	Good	3-10x faster
Concurrency	Single-threaded	Thread-safe with async-mutex
Best For	Small graphs, debugging	Large graphs (10k+ entities)

Using SQLite:

{
  "mcpServers": {
    "memory": {
      "command": "node",
      "args": ["/path/to/memory-mcp/dist/index.js"],
      "env": {
        "MEMORY_STORAGE_TYPE": "sqlite",
        "MEMORY_FILE_PATH": "/path/to/data/memory.db"
      }
    }
  }
}

Storage Files

When you set MEMORY_FILE_PATH, the server automatically creates related files:

/your/data/directory/
├── memory.jsonl                    # Main knowledge graph
├── memory-saved-searches.jsonl     # Saved search queries
├── memory-tag-aliases.jsonl        # Tag synonym mappings
└── .backups/                       # Timestamped backups
    ├── backup_2026-01-08_10-30-00-123.jsonl
    └── backup_2026-01-08_10-30-00-123.jsonl.meta.json

Migration Tool

Convert between JSONL and SQLite formats:

cd tools/migrate-from-jsonl-to-sqlite
npm install && npm run build

# JSONL to SQLite
node dist/migrate-from-jsonl-to-sqlite.js --from memory.jsonl --to memory.db

# SQLite to JSONL
node dist/migrate-from-jsonl-to-sqlite.js --from memory.db --to memory.jsonl

Development

Prerequisites

Node.js 18+
npm 9+
TypeScript 5.6+

Build Commands

npm install           # Install dependencies
npm run build         # Build TypeScript
npm test              # Run tests (791 tests across 36 files; ~85% coverage)
npm run typecheck     # Strict type checking
npm run watch         # Development watch mode
npm run clean         # Remove dist/ directory
npm run docs:deps     # Generate dependency graph

Architecture

After the Phase 13 extraction, this repo is a thin MCP wrapper. All graph logic, managers, and storage live in @danielsimonjr/memoryjs (currently ^3.0.0).

memory-mcp (this repo)              @danielsimonjr/memoryjs (npm dep)
┌──────────────────────────┐        ┌──────────────────────────────────┐
│  src/index.ts            │        │  ManagerContext (lazy init)      │
│  src/server/MCPServer.ts │───────▶│  EntityManager, RelationManager  │
│  src/server/toolDefs.ts  │imports │  SearchManager, IOManager, etc.  │
│  src/server/toolHandlers │        │  GraphStorage / SQLiteStorage    │
│  src/server/responseComp.│        │  StorageFactory + 100+ modules   │
└──────────────────────────┘        └──────────────────────────────────┘
       5 source files                  77+ source files (extracted)
       MCP protocol + dispatch         All graph + search + storage

Layer	Lives in	Files
MCP protocol (stdio transport, tool registration, dispatch)	`memory-mcp`	5
Tool schemas (241 tools across 65 categories)	`memory-mcp` (`toolDefinitions.ts`)	1
Handler registry + Zod validation + response compression	`memory-mcp` (`toolHandlers.ts` + `responseCompressor.ts`)	2
Managers (Entity / Relation / Search / IO / Tag / Hierarchy / Analytics / Compression / Archive / GraphTraversal / SemanticSearch / RankedSearch / etc.)	`memoryjs`	100+
Storage (JSONL + SQLite with FTS5 + StorageFactory + TransactionManager)	`memoryjs`	—
Embedding providers (OpenAI / local / none) + VectorStore	`memoryjs`	—

Project Structure

memory-mcp/
├── src/                                    # Source (5 TypeScript files)
│   ├── index.ts                            # Entry point: ManagerContext + start MCPServer; re-exports memoryjs types
│   └── server/
│       ├── MCPServer.ts                    # MCP Server setup, stdio transport, request handlers
│       ├── toolDefinitions.ts              # 241 tool schemas (name, description, inputSchema)
│       ├── toolHandlers.ts                 # Handler registry: validate args → call manager → format response
│       └── responseCompressor.ts           # Brotli + base64 wrapper for >256KB payloads
├── tests/                                  # Test suite (36 files, 791 tests, ~85% statement coverage)
│   ├── unit/                               # Unit tests (response compressor, tool defs, validate-fact handler)
│   ├── integration/                        # MCP server lifecycle
│   ├── e2e/tools/                          # Per-category tool tests + handler-smoke broad coverage
│   ├── knowledge-graph.test.ts             # Core graph operations (smoke against memoryjs)
│   └── file-path.test.ts                   # Storage path resolution
├── dist/                                   # Compiled output (rebuilt on `npm install` via `prepare`)
├── docs/                                   # Documentation
│   ├── architecture/                       # API.md, ARCHITECTURE.md, COMPONENTS.md, OVERVIEW.md, TEST_COVERAGE.md
│   ├── guides/                             # HIERARCHY.md, COMPRESSION.md, ARCHIVING.md, QUERY_LANGUAGE.md
│   ├── development/                        # WORKFLOW.md
│   ├── roadmap/                            # FUTURE_FEATURES.md, PERFORMANCE_AND_CAPABILITIES.md
│   └── reports/                            # Historical sprint reports
├── tools/                                  # Standalone utilities (each builds independently)
│   ├── chunking-for-files/                 # File splitting
│   ├── compress-for-context/               # CTON compression
│   ├── create-dependency-graph/            # Dependency analyzer
│   └── migrate-from-jsonl-to-sqlite/       # Storage backend converter
├── CHANGELOG.md                            # Version history
└── README.md                               # This file

Dependencies

Production (3 direct deps — everything else is transitive via memoryjs):

@danielsimonjr/memoryjs: ^1.15.0 — knowledge graph engine (storage, managers, search, embeddings, RBAC, OCC, bitemporal, causal, etc.)
@modelcontextprotocol/sdk: ^1.21.1 — MCP protocol implementation
zod: ^3.24.1 — runtime input validation (schemas re-exported from memoryjs)

Development:

typescript: ^5.6.2
vitest: ^4.0.13
@vitest/coverage-v8: ^4.0.13
shx: ^0.4.0 — cross-platform shell commands for clean script
@types/node: ^22

Note: better-sqlite3, async-mutex, @danielsimonjr/workerpool, and the embedding providers (OpenAI / @xenova/transformers) are transitive deps via @danielsimonjr/memoryjs since the Phase 13 extraction. They are not listed in this repo's package.json.

Documentation

Comprehensive documentation in docs/:

Architecture

API.md - Complete API documentation for all 241 tools
ARCHITECTURE.md - Technical architecture and system design
COMPONENTS.md - Component breakdown and responsibilities
OVERVIEW.md - High-level project overview
DEPENDENCY_GRAPH.md - Module dependencies

User Guides

HIERARCHY.md - Parent-child relationships (9 tools)
COMPRESSION.md - Duplicate detection and merging
ARCHIVING.md - Memory lifecycle and archiving
QUERY_LANGUAGE.md - Boolean search syntax

Development

WORKFLOW.md - Development procedures
MIGRATION.md - Version upgrade guide

Companion skill

This plugin ships a memory skill (memory-mcp:memory, /memory) — a playbook over the knowledge-graph tools covering graph CRUD/search/maintenance, project indexing, and storage migration. See skills/memory/SKILL.md.

Contributing

We welcome contributions!

See:

CONTRIBUTING.md - Contribution guidelines
CODE_OF_CONDUCT.md - Community standards

Ways to Help:

Report bugs
Request features
Submit pull requests
Improve documentation
Add tests

Changelog

All notable changes are documented in CHANGELOG.md.

Current version: v12.7.2 - View full changelog

Recent highlights:

v12.7.2: Bumped @danielsimonjr/memoryjs ^3.0.0 → ^3.1.0 — Node 24 better-sqlite3 prebuilds (^12.11.1) and the llamacpp embedding provider (MEMORY_EMBEDDING_PROVIDER=llamacpp + MEMORY_EMBEDDING_BASE_URL). No new tools.
v12.7.0 (241 tools): Upgraded @danielsimonjr/memoryjs ^2.8.1 → ^3.0.0 and surfaced its new features as 16 tools — event memory (5), reconstructive Cue–Tag–Content memory + snapshot persistence (5), relation consolidation (2), agent reflection (4) — plus v3 graph-channel / evidence-path options on hybrid_search. Refactored handlers onto the new ManagerContext accessors (hybridSearchManager, governanceManager, eventManager, reflectionManager, reconstructiveMemory(), close()).
v12.5.0 (225 tools): 10 engineering / diagnostic tools mirroring the memoryjs CLI surface (diag, health, check_graph, reindex, cache stats/clear, graph_size, inspect_entity, hierarchy_tree, entity_neighbors).
v12.3.2 (215 tools): Backport of the deferred set_project_scope / get_project_scope pair.
v12.3.0 (213 tools): Phase 16 — 53 new tools surfacing memoryjs v2.1.0 across seven new manager surfaces: do_not_remember exclusion rules (5), decision rationale + ADR markdown dual-write (10), structured project context (12), heuristic guidelines (10), tool affordance + ToolCallObserver producer pipeline (11), observation dedup (2), spell correction (3). Bumped @danielsimonjr/memoryjs dep ^1.15.0 → ^2.1.0.
v12.2.3: Publishability — switched @danielsimonjr/memoryjs dep from local file: link to published ^1.15.0 (npm rejects file: deps for published packages).
v12.2.2: Doc-only — roadmap completion audit grading Phase 6-15 status against current code.
v12.2.1: Doc-only — comprehensive consistency pass across 68 markdown documents to align with v12.2.0's 160-tool surface.
v12.2.0 (160 tools): 23 new tools — entity bitemporal validity (η.4.4), OCC update (η.5.5.c), RBAC (η.6.1), procedural memory (3B.4), active retrieval (3B.5), causal reasoning (3B.6), world model (3B.7), plus W3C Linked Data exports (η.5.4) and PII redaction (η.6.3) wired into existing export_graph. Plus four pre-publish fixes from end-to-end MCP smoke testing (memoryjs v1.14+).
v12.1.0 (106 tools): 12 new tools — Project Scoping, Memory Versioning, Semantic Forget, Profiles, Temporal KG, Ingestion, Agent Diary (memoryjs v1.8.0/v1.9.0)
v12.0.0 (94 tools): 32 new tools — Ref Index, Artifacts, Temporal Search, Distillation, Freshness, LLM Query, Governance, Role Profiles, Entropy, Consolidation, Formatter, Collaborative, Failure Handling, Cognitive Load
v11.1.1: npm tarball cleanup, excluded data files from published package
v11.1.0: MCP error framing, dynamic server version, handler smoke tests, response compressor tests

License

MIT License - see LICENSE

Acknowledgments

Original Project

Enhanced fork of Model Context Protocol memory server by Anthropic.

Developer

Daniel Simon Jr.

Major Enhancements

Hierarchical nesting with parent-child relationships
Graph algorithms: path finding, centrality, connected components
Semantic search with embedding-based similarity
Brotli compression for backups, exports, and responses
Memory compression with intelligent duplicate detection
Smart archiving with criteria-based filtering
Advanced search: TF-IDF, boolean, and fuzzy matching
Multi-format import/export with merge strategies
SQLite backend with better-sqlite3 (3-10x faster)
Transaction support with ACID guarantees
Comprehensive test suite (791 tests, 36 test files in this wrapper repo; full-coverage core graph tests live in @danielsimonjr/memoryjs)

Repository: https://github.com/danielsimonjr/memory-mcp NPM: https://www.npmjs.com/package/@danielsimonjr/memory-mcp Issues: https://github.com/danielsimonjr/memory-mcp/issues

Name		Name	Last commit message	Last commit date
.claude-plugin		.claude-plugin
.claude		.claude
.github		.github
.vscode		.vscode
bundle		bundle
docs		docs
scripts		scripts
skills/memory		skills/memory
src		src
tests		tests
tools		tools
.dropboxignore		.dropboxignore
.gitattributes		.gitattributes
.gitignore		.gitignore
.mcp.json		.mcp.json
.note		.note
.npmignore		.npmignore
.npmrc		.npmrc
CHANGELOG.md		CHANGELOG.md
CLAUDE.md		CLAUDE.md
CODE_OF_CONDUCT.md		CODE_OF_CONDUCT.md
CONTRIBUTING.md		CONTRIBUTING.md
LICENSE		LICENSE
README.md		README.md
SECURITY.md		SECURITY.md
TODO.md		TODO.md
bun.lock		bun.lock
package-lock.json		package-lock.json
package.json		package.json
sbom.json		sbom.json
tsconfig.json		tsconfig.json
vitest.config.ts		vitest.config.ts

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