Helix Memory - Long-Term Memory for Claude Code

Store and retrieve persistent memory across sessions using HelixDB's graph-vector database. Features semantic search (via Ollama), reasoning chains (IMPLIES/CONTRADICTS/BECAUSE), time-window filtering, and hybrid search.

IMPORTANT: Always Use the Bash CLI

ALWAYS use the memory bash script - never call Python scripts directly.

Whitelisting

The memory CLI is globally whitelisted via symlink:

~/Tools/memory → ~/.claude/skills/helix-memory/memory

Whitelist pattern in settings.json:

"Bash(~/Tools/memory:*)"

This means:

All memory commands run without permission prompts
Agents inherit this whitelist
Use ~/Tools/memory (shorter = fewer tokens)

Usage

~/Tools/memory <command>

Service Commands (Start/Stop)

# Start HelixDB (auto-starts Docker Desktop if needed)
memory start

# Stop HelixDB
memory stop

# Restart
memory restart

# Check status
memory status

Memory Commands

# Search memories
memory search "topic"

# List all (sorted by importance)
memory list --limit 10

# Store (all aliases work identically - auto-categorize by default)
memory store "User prefers FastAPI over Flask"
memory add "User prefers FastAPI over Flask"
memory remember "User prefers FastAPI over Flask"
memorize "User prefers FastAPI over Flask"

# Store with explicit flags (skips auto-categorization)
memory store "content" -t preference -i 9 -g "tags"

# Store solution with link to problem
memory store "Fix: use async/await" -t solution --solves abc123

# Delete by ID (prefix OK)
memory delete abc123

# Find by tag
memory tag "wordpress"

# Show memory details with edges
memory show abc123

# Link memories (see Graph Relationships section)
memory link <from_id> <to_id> --type solves

# Help
memory help

Python API (For hooks/advanced use only)

The common.py module provides high-level functions:

import sys
sys.path.insert(0, '/path/to/helix-memory/hooks')
from common import (
    # Storage
    store_memory, store_memory_embedding, generate_embedding,
    # Retrieval
    get_all_memories, get_high_importance_memories,
    # Search
    search_by_similarity, search_by_text, hybrid_search,
    get_memories_by_time_window,
    # Reasoning chains
    create_implication, create_contradiction, create_causal_link, create_supersedes,
    get_implications, get_contradictions, get_reasoning_chain,
    # Utils
    check_helix_running, ensure_helix_running
)

Key Features

1. Semantic Search (Ollama)

Real vector similarity using nomic-embed-text model:

# Search finds semantically related content, not just keywords
results = search_by_similarity("verify code works", k=5)
# Finds: "test before completing" even without keyword match

2. Time-Window Search

Filter memories by recency:

# Time windows: "recent" (4h), "contextual" (30d), "deep" (90d), "full" (all)
recent = get_memories_by_time_window("recent")      # Last 4 hours
contextual = get_memories_by_time_window("contextual")  # Last 30 days
all_time = get_memories_by_time_window("full")      # Everything

3. Hybrid Search

Combines vector similarity + text matching for best results:

results = hybrid_search("python testing preferences", k=10, window="contextual")

4. Problem-Solution Linking

Link solutions to the problems they solve using the --type solves edge:

# Link existing memories
memory link <solution_id> <problem_id> --type solves

# Store solution with auto-link
memory store "Fix: use async/await for DB calls" -t solution --solves <problem_id>

3-Step Workflow for Problem-Solution Linking:

Identify the problem - Find/store the problem memory: memory search "timeout error"
Store/find the solution - memory store "Fix: use connection pooling" -t solution
Link them - memory link <solution_id> <problem_id> --type solves

View linked solutions: memory show <problem_id> displays --SOLVED BY-- section.

5. Reasoning Chains (Graph Power!)

Create logical relationships between memories:

# "prefers Python" IMPLIES "avoid Node.js suggestions"
create_implication(python_pref_id, avoid_node_id, confidence=9, reason="Language preference")

# "always use tabs" CONTRADICTS "always use spaces"
create_contradiction(tabs_id, spaces_id, severity=8, resolution="newer_wins")

# "migrated to FastAPI" BECAUSE "Flask too slow"
create_causal_link(fastapi_id, flask_slow_id, strength=9)

# New preference SUPERSEDES old one
create_supersedes(new_pref_id, old_pref_id)

Query reasoning chains:

implications = get_implications(memory_id)    # What does this imply?
contradictions = get_contradictions(memory_id)  # What conflicts with this?
chain = get_reasoning_chain(memory_id)        # Full reasoning graph

Memory Categories

| Category | Importance | Description | |----------|------------|-------------| | preference | 7-10 | User preferences that guide interactions | | fact | 5-9 | Factual info about user/projects/environment | | context | 4-8 | Project/domain background | | decision | 6-10 | Architectural decisions with rationale | | task | 3-9 | Ongoing/future tasks | | solution | 6-9 | Bug fixes, problem solutions |

Storing Memories

Basic Storage

memory_id = store_memory(
    content="User prefers Python over Node.js for backend",
    category="preference",
    importance=9,
    tags="python,nodejs,backend,language",
    source="session-abc123"  # or "manual"
)

With Semantic Embedding

# Generate real embedding via Ollama
vector, model = generate_embedding(content)

# Store embedding for semantic search
store_memory_embedding(memory_id, vector, content, model)

Retrieving Memories

Get All/Filtered

all_mems = get_all_memories()
important = get_high_importance_memories(min_importance=8)
prefs = [m for m in all_mems if m.get('category') == 'preference']

Search

# Semantic (finds related meanings)
results = search_by_similarity("testing workflow", k=10)

# Text (exact substring match)
results = search_by_text("pytest")

# Hybrid (best of both)
results = hybrid_search("python testing", k=10, window="contextual")

Schema Overview

Nodes

Memory: content, category, importance, tags, source, created_at
MemoryEmbedding: vector (1536-dim), content, model
Context: name, description, context_type
Concept: name, concept_type, description

Reasoning Edges

Implies: Memory → Memory (confidence, reason)
Contradicts: Memory → Memory (severity, resolution)
Because: Memory → Memory (strength)
Supersedes: Memory → Memory (superseded_at)

Structural Edges

HasEmbedding: Memory → MemoryEmbedding
BelongsTo: Memory → Context
RelatedToConcept: Memory → Concept
RelatesTo: Memory → Memory (generic)

REST API Endpoints

All endpoints: POST http://localhost:6969/{endpoint} with JSON body.

Storage

# Store memory
curl -X POST http://localhost:6969/StoreMemory -H "Content-Type: application/json" \
  -d '{"content":"...", "category":"preference", "importance":9, "tags":"...", "source":"manual"}'

# Create implication
curl -X POST http://localhost:6969/CreateImplication -H "Content-Type: application/json" \
  -d '{"from_id":"...", "to_id":"...", "confidence":8, "reason":"..."}'

Retrieval

# Get all memories
curl -X POST http://localhost:6969/GetAllMemories -H "Content-Type: application/json" -d '{}'

# Get implications
curl -X POST http://localhost:6969/GetImplications -H "Content-Type: application/json" \
  -d '{"memory_id":"..."}'

# Vector search
curl -X POST http://localhost:6969/SearchBySimilarity -H "Content-Type: application/json" \
  -d '{"query_vector":[...], "k":10}'

Automatic Memory (Hooks)

Memory storage/retrieval happens automatically via Claude Code hooks:

UserPromptSubmit (load_memories.py): Loads relevant memories before processing
Stop (reflect_and_store.py): Analyzes conversation, stores important items (every 5 prompts)
SessionStart (session_start.py): Initializes session context

What Gets Auto-Stored

Explicit: "remember this:", "store this:"
Preferences: "I prefer...", "always use...", "never..."
Decisions: "decided to...", "let's use..."
Bug fixes: "the issue was...", "fixed by..."

CLI Reference

# Service
memory start      # Start HelixDB (auto-starts Docker Desktop)
memory stop       # Stop HelixDB
memory restart    # Restart HelixDB
memory status     # Check status and memory count

# Memory operations
memory search "pytest"
memory list --limit 10
memory store/add/remember/rem "content"  # All auto-categorize
memory store "content" -t cat -i imp -g "tags"  # Explicit flags
memory store "solution" -t solution --solves <problem_id>  # Link solution to problem
memory delete <memory-id>
memory tag "tagname"
memory show <memory-id>    # Show details with edges
memory help

# Graph operations (linking memories)
memory link <from_id> <to_id> --type <edge_type>

Link Command & Edge Types

The memory link command creates graph edges between memories:

memory link <from_id> <to_id> --type <edge_type>

Available edge types:

| Edge Type | Direction | Use Case | |-----------|-----------|----------| | solves | solution → problem | Link a fix to the bug it solves | | solved_by | problem → solution | Link a bug to its fix | | supersedes | new → old | New preference replaces old | | implies | A → B | A logically implies B | | contradicts | A ↔ B | A and B conflict | | leads_to | cause → effect | Causal chain | | supports | evidence → claim | Supporting evidence | | related | A ↔ B | Generic relationship (default) |

Examples:

# Solution solves a problem
memory link sol_abc123 prob_def456 --type solves

# New preference supersedes old
memory link new_pref old_pref --type supersedes

# One decision implies another
memory link use_fastapi avoid_flask --type implies

Show Command

memory show <id> displays memory details and linked edges:

memory show abc123

Output includes relationship sections:

--SOLVED BY-- - Solutions for problems
--SOLVES-- - Problems solved by solutions
--IMPLIES-- - Logical implications
--CONTRADICTS-- - Conflicts
--SUPERSEDES-- - Replaced memories
--RELATED-- - Generic relationships

Project Tagging

Memories are automatically tagged with project names based on working directory. Project detection uses directory name as fallback.

Ollama Setup (For Real Semantic Search)

# Start Ollama service
brew services start ollama

# Pull embedding model (274MB)
ollama pull nomic-embed-text

# Verify
curl http://localhost:11434/api/tags

Without Ollama, falls back to Gemini API (if key set) or hash-based pseudo-embeddings.

Best Practices

DO:

Store preferences immediately when expressed
Use reasoning chains to link related memories
Set appropriate importance (10=critical, 7-9=high, 4-6=medium, 1-3=low)
Use hybrid_search for best recall
Filter by time window to prioritize recent info

DON'T:

Store code snippets (use codebase)
Store sensitive data (passwords, keys)
Create duplicate memories (use find_similar_memories first)
Forget embeddings (needed for semantic search)

Troubleshooting

DB Won't Start

# Use the memory script (handles Docker auto-start)
memory start

# Check container status
docker ps | grep helix

Ollama Not Working

brew services restart ollama
ollama list  # Should show nomic-embed-text

Vector Dimension Errors

HelixDB expects 1536-dim vectors. The code auto-pads smaller embeddings.

Check Logs

docker logs $(docker ps -q --filter "name=helix-memory") 2>&1 | tail -20

Resources

Helix CLI: ~/.local/bin/helix
HelixDB Docs: https://docs.helix-db.com
Ollama: https://ollama.ai