yantrikdb-mcp 0.6.0

YantrikDB MCP Server — Cognitive memory for AI agents

YantrikDB MCP Server

Cognitive memory for AI agents. Works with Claude Code, Cursor, Windsurf, and any MCP-compatible client.

Website: yantrikdb.com · Docs: yantrikdb.com/guides/mcp · GitHub: yantrikos/yantrikdb-mcp

Install

# Default — uses the engine's bundled 64-dim embedder. ~10 MB install,
# ~80 ms cold start, no native ML deps.
pip install yantrikdb-mcp

# Optional: higher-quality 384-dim ONNX MiniLM-L6-v2 embedder (~150 MB install).
# Auto-used when an existing pre-v0.6 database is detected.
pip install 'yantrikdb-mcp[onnx]'

Upgrading from v0.5.x? Your existing database stays at 384 dim — install the [onnx] extra to keep using it transparently. New installs default to the lean bundled embedder. See Embedder backends below.

Configure

The MCP server has three deployment modes. Pick the one that fits your setup.

Mode 1 — Local (default, recommended for single user)

The MCP server runs the engine in-process with a local SQLite database. Fast, private, zero dependencies.

{
  "mcpServers": {
    "yantrikdb": {
      "command": "yantrikdb-mcp"
    }
  }
}

That's it. The agent auto-recalls context, auto-remembers decisions, and auto-detects contradictions — no prompting needed.

Mode 2 — HTTP Cluster (recommended for shared/multi-machine setups)

Forward all tool calls to a YantrikDB HTTP cluster instead of using an embedded engine. The MCP server is a thin stateless client — all memories live on the cluster, accessible from any machine.

Benefits: shared memory across machines, high availability, no local embedder download, no local database.

{
  "mcpServers": {
    "yantrikdb": {
      "command": "yantrikdb-mcp",
      "env": {
        "YANTRIKDB_SERVER_URL": "http://node1:7438,http://node2:7438",
        "YANTRIKDB_TOKEN": "ydb_your_database_token"
      }
    }
  }
}

• Comma-separate multiple nodes for Raft cluster auto-discovery
• Automatic leader-following on failover
• 15s request timeout
• Get the token from the cluster: yantrikdb token create --db your_database

Mode 3 — SSE Server (legacy, single remote instance)

Run the MCP server itself as a long-running SSE server with its own embedded database. Clients connect via HTTP streaming.

# Generate a secure API key
export YANTRIKDB_API_KEY=$(python -c "import secrets; print(secrets.token_urlsafe(32))")

# Start SSE server
yantrikdb-mcp --transport sse --port 8420

{
  "mcpServers": {
    "yantrikdb": {
      "type": "sse",
      "url": "http://your-server:8420/sse",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY"
      }
    }
  }
}

Supports sse and streamable-http transports. Note: SSE connections can drop on idle — Mode 2 (HTTP Cluster) is more reliable for shared deployments.

Environment Variables

Variable	Used in Mode	Default	Description
YANTRIKDB_SERVER_URL	Cluster	(unset → local mode)	Comma-separated cluster node URLs
YANTRIKDB_TOKEN	Cluster	(none)	Bearer token for the cluster database
YANTRIKDB_DB_PATH	Local	~/.yantrikdb/memory.db	Database file path
YANTRIKDB_EMBEDDER	Local	auto	Backend selector: auto | bundled | onnx
YANTRIKDB_EMBEDDING_MODEL	Local	all-MiniLM-L6-v2	ONNX model name (only used when YANTRIKDB_EMBEDDER=onnx)
YANTRIKDB_API_KEY	SSE server	(none)	Bearer token when serving SSE/HTTP

Embedder backends

Local mode ships two embedders. The MCP picks one automatically; override with YANTRIKDB_EMBEDDER.

Backend	Dim	Cold start	Install size	When it's used
bundled (engine default)	64	~80 ms	~10 MB	New / empty databases
onnx (MiniLM-L6-v2)	384	~2 s	~150 MB	Existing pre-v0.6 databases (auto-detected), or when set explicitly

auto (default) reads the SQLite file at YANTRIKDB_DB_PATH and picks onnx if it already contains memories — preserving recall quality on upgrades — and bundled otherwise. Set YANTRIKDB_EMBEDDER=bundled or =onnx to override.

If you set YANTRIKDB_EMBEDDER=onnx (or auto-detection picks it) without installing the extras, the server fails fast with an install hint:

RuntimeError: Existing DB has memories embedded with the 384-dim ONNX
model, but ONNX deps are missing.
  Install with:  pip install 'yantrikdb-mcp[onnx]'

Why Not File-Based Memory?

File-based memory (CLAUDE.md, memory files) loads everything into context every conversation. YantrikDB recalls only what's relevant.

Benchmark: 15 queries × 4 scales

Memories	File-Based	YantrikDB	Savings	Precision
100	1,770 tokens	69 tokens	96%	66%
500	9,807 tokens	72 tokens	99.3%	77%
1,000	19,988 tokens	72 tokens	99.6%	84%
5,000	101,739 tokens	53 tokens	99.9%	88%

Selective recall is O(1). File-based memory is O(n).

• At 500 memories, file-based exceeds 32K context windows
• At 5,000, it doesn't fit in any context window — not even 200K
• YantrikDB stays at ~70 tokens per query, under 60ms latency
• Precision improves with more data — the opposite of context stuffing

Run the benchmark yourself: python benchmarks/bench_token_savings.py

Tools

15 tools, full engine coverage:

Tool	Actions	Purpose
remember	single / batch	Store memories — decisions, preferences, facts, corrections
recall	search / refine / feedback	Semantic search, refinement, and retrieval feedback
forget	single / batch	Tombstone memories
correct	—	Fix incorrect memory (preserves history)
think	—	Consolidation + conflict detection + pattern mining
memory	get / list / search / update_importance / archive / hydrate	Manage individual memories + keyword search
graph	relate / edges / link / search / profile / depth	Knowledge graph operations
conflict	list / get / resolve / reclassify	Handle contradictions and teach substitution patterns
trigger	pending / history / acknowledge / deliver / act / dismiss	Proactive insights and warnings
session	start / end / history / active / abandon_stale	Session lifecycle management
temporal	stale / upcoming	Time-based memory queries
procedure	learn / surface / reinforce	Procedural memory — learn and reuse strategies
category	list / members / learn / reset	Substitution categories for conflict detection
personality	get / set	AI personality traits from memory patterns
stats	stats / health / weights / maintenance	Engine stats, health, weights, and index rebuilds

See yantrikdb.com/guides/mcp for full documentation.

Examples

1. Auto-recall at conversation start

User: "What did we decide about the database migration?"

The agent automatically calls recall("database migration decision") and retrieves relevant memories before responding — no manual prompting needed.

2. Remember decisions + build knowledge graph

User: "We're going with PostgreSQL for the new service. Alice will own the migration."

The agent calls:

• remember(text="Decided to use PostgreSQL for the new service", domain="architecture", importance=0.8)
• remember(text="Alice owns the PostgreSQL migration", domain="people", importance=0.7)
• graph(action="relate", entity="Alice", target="PostgreSQL Migration", relationship="owns")

3. Contradiction detection

After storing "We use Python 3.11" and later "We upgraded to Python 3.12", calling think() detects the conflict. The agent surfaces it:

"I found a contradiction: you previously said Python 3.11, but recently mentioned Python 3.12. Which is current?"

Then resolves with conflict(action="resolve", conflict_id="...", strategy="keep_b").

Privacy Policy

YantrikDB MCP Server stores all data locally on your machine (default: ~/.yantrikdb/memory.db). No data is sent to external servers, no telemetry is collected, and no third-party services are contacted during operation.

• Data collection: Only what you explicitly store via the remember tool or what the AI agent stores on your behalf.
• Data storage: Local SQLite database on your filesystem. You control the path via YANTRIKDB_DB_PATH.
• Third-party sharing: None. Data never leaves your machine in local (stdio) mode.
• Network mode: When using SSE/HTTP transport, data travels between your client and your self-hosted server. No Anthropic or third-party servers are involved.
• Embedding model: Uses a local ONNX model (all-MiniLM-L6-v2). Model files are downloaded once from Hugging Face Hub on first use, then cached locally.
• Retention: Data persists until you delete it (forget tool) or delete the database file.
• Contact: [e-mail]

Full policy: yantrikdb.com/privacy

Contributing

See CONTRIBUTING.md for a venv setup, running pytest, and opening PRs.

Support

• Issues: github.com/yantrikos/yantrikdb-mcp/issues
• Email: [e-mail]
• Docs: yantrikdb.com/guides/mcp

License

This MCP server is licensed under MIT — use it freely in any project.

Note: This package depends on yantrikdb (the cognitive memory engine), which is licensed under AGPL-3.0. The AGPL applies to the engine itself — if you modify the engine and distribute it or provide it as a network service, those modifications must also be AGPL-3.0. Using the engine as-is via this MCP server does not trigger AGPL obligations on your code.