agentmem

mcp-name: io.github.oxgeneral/agentmem

Lightweight persistent memory for AI agents. One SQLite file. Hybrid search (keywords + semantics). Zero to 12MB install.

No PyTorch. No cloud. No server. Just memory.

Why

Every AI agent session starts from zero. Context windows compress, conversations end, memory vanishes. agentmem gives agents persistent memory that survives across sessions — in a single SQLite file.

• Hybrid search: FTS5 full-text keywords + vector semantic search, fused with adaptive ranking
• 4 operational modes: from zero dependencies (stdlib only) to best quality (12MB)
• 16 MCP tools: recall, remember, save_state, compact, consolidate, entities, and more
• HTTP REST API: 14 endpoints, zero-dependency server, CORS-ready
• 5 memory tiers: core, learned, episodic, working (auto-expires), procedural (behavioral rules)
• Namespaces: multi-user, multi-agent memory isolation
• Temporal versioning: fact evolution chains with supersedes tracking
• Entity extraction: auto-extracts @mentions, URLs, IPs, env vars, money amounts
• Conversation extraction: auto-extracts facts, decisions, TODOs from chat history
• Importance scoring: auto-scores memories by tier, length, specificity, structure
• Memory consolidation: finds and merges near-duplicate memories
• Recency boost: newer memories rank higher with configurable decay
• Multilingual: Russian keywords via FTS5, English semantics via embeddings
• Fast: <1ms/query hybrid search, <5ms cold start, <0.2ms/chunk import

Install

# Best quality (sqlite-vec + model2vec, 12MB total)
pip install agentmem[all]

# Minimal (sqlite-vec + hash embeddings, 151KB)
pip install agentmem

# Zero dependencies (pure Python, stdlib only)
pip install agentmem --no-deps

Quick Start

Python API

from agentmem import MemoryStore, get_embedding_model

# Auto-selects best available backend
embed = get_embedding_model()
store = MemoryStore("memory.db", embedding_dim=embed.dim)
store.set_embed_fn(embed)

# Store memories with namespaces
store.remember("Server costs $50/month", tier="core", namespace="infra")
store.remember("API returns 403 without auth", tier="learned", namespace="api")
store.remember("Deployed v2.1 at 15:30", tier="episodic")

# Search — hybrid keyword + semantic, with recency boost
results = store.recall("server costs", recency_weight=0.15)

# Namespace isolation
results = store.recall("server", namespace="infra")

# Save working state before context compression
store.save_state("Working on auth fix, step 3/5, blocked by CORS")

# Add behavioral rules (procedural memory)
store.add_procedure("Always use HTTPS in production")
store.add_procedure("Never expose debug endpoints")
rules = store.get_procedures()  # → formatted for system prompt

# Update facts with version chain
store.update_memory(old_id=1, new_content="Server costs $75/month")
history = store.history(memory_id=2)  # → trace fact evolution

# Find related memories by entity
related = store.related("10.0.0.1")  # → all memories mentioning this IP
entities = store.entities(entity_type="ip")  # → list all known IPs

# Auto-extract from conversations
messages = [
    {"role": "user", "content": "Set API_KEY to sk-abc123. Always validate input."},
    {"role": "assistant", "content": "Noted. I decided to use pydantic for validation."},
]
result = store.process_conversation(messages, namespace="project")
# → extracts config, preferences, decisions automatically

# Maintenance
store.compact(max_age_days=90)  # archive old low-value memories
store.consolidate(similarity_threshold=0.85)  # merge near-duplicates

# Import markdown files
store.import_markdown("MEMORY.md", tier="core")

CLI

# Initialize database
agentmem init --db memory.db

# Import markdown files
agentmem import MEMORY.md --tier core -n my-agent
agentmem import-dir ./daily-logs/ --tier episodic

# Search with namespace filter
agentmem search "deployment process" --limit 5 -n infra

# Manage procedures
agentmem add-procedure "Always use markdown formatting"
agentmem procedures

# View entities and relations
agentmem entities --type ip
agentmem related 10.0.0.1

# Maintenance
agentmem compact --max-age-days 90 --dry-run
agentmem consolidate --threshold 0.85

# Process conversation
agentmem process chat.json -n project

# Stats and export
agentmem stats
agentmem export --tier core

MCP Server (stdio)

python -m agentmem --db memory.db

Add to your MCP client config:

{
  "mcpServers": {
    "memory": {
      "command": "python",
      "args": ["-m", "agentmem", "--db", "/path/to/memory.db"]
    }
  }
}

HTTP REST API

# Start HTTP server
agentmem serve-http --port 8422

# Or directly
agentmem-http --port 8422 --db memory.db

# Store a memory
curl -X POST http://localhost:8422/remember \
  -H "Content-Type: application/json" \
  -d '{"content": "Server IP is 10.0.0.1", "tier": "core", "namespace": "infra"}'

# Search
curl "http://localhost:8422/recall?query=server+IP&namespace=infra"

# Health check
curl http://localhost:8422/health

16 MCP tools / 14 HTTP endpoints:

Memory Tiers

Namespaces

Isolate memories per user, agent, or project:

# Store in namespaces
store.remember("Alice's API key", namespace="user/alice")
store.remember("Bob's config", namespace="user/bob")
store.remember("Shared fact", namespace="team")

# Search within namespace (prefix matching)
store.recall("API", namespace="user/alice")  # only Alice's memories
store.recall("API", namespace="user")  # Alice + Bob (prefix match)
store.recall("API")  # everything

Temporal Versioning

Track how facts evolve over time:

# Initial fact
r1 = store.remember("Server costs $50/month", tier="core")

# Fact changes — old version archived, linked via supersedes
r2 = store.update_memory(r1["id"], "Server costs $75/month")

# Trace the history
history = store.history(r2["id"])
# → [{"id": 2, "content": "...$75..."}, {"id": 1, "content": "...$50..."}]

Entity Extraction

Automatic regex-based NER on every remember() call:

# Find all memories mentioning an entity
store.related("10.0.0.1")
store.related("@alice", entity_type="mention")

# List all known entities
store.entities()  # sorted by memory count
store.entities(entity_type="ip")

Conversation Auto-Extraction

Auto-extract memories from chat history (regex-only, no LLM):

messages = [
    {"role": "user", "content": "Set DATABASE_URL to postgres://localhost/mydb"},
    {"role": "assistant", "content": "I decided to use connection pooling. Important: max 20 connections."},
    {"role": "user", "content": "Always validate input. TODO: add rate limiting."},
]
result = store.process_conversation(messages)
# Extracts: config→core, decisions→episodic, preferences→procedural, todos→working, important→core

Operational Modes

agentmem automatically selects the best available mode:

*With lazy loading — model2vec loads on first query, not on init

Architecture

┌──────────────────────────────────────────────┐
│              MemoryStore                      │
│  ┌──────────┐  ┌──────────┐  ┌────────────┐  │
│  │  FTS5    │  │  Vector  │  │  Entity    │  │
│  │ keywords │  │  Index   │  │  Index     │  │
│  │ + BM25   │  │ cosine   │  │  regex NER │  │
│  └────┬─────┘  └────┬─────┘  └─────┬──────┘  │
│       └──────┬───────┘              │         │
│    Adaptive Hybrid Scorer           │         │
│  (query classify + recency +        │         │
│   importance boost)                 │         │
│  ┌──────────────────────────────────┴───────┐ │
│  │            SQLite + WAL                  │ │
│  │  memories │ memories_fts │ vecs │ entities│ │
│  └──────────────────────────────────────────┘ │
│            One file: memory.db                │
└───────────────────────────────────────────────┘

Comparison

License

MIT