# Mem0 Local Hermes Plugin

Self-hosted Mem0 memory provider for Hermes-Agent. Provides semantic memory search, automatic fact extraction, and context injection without tool calls.

## Features

- **Local Mem0 server** — No cloud dependency, full data privacy
- **Async prefetch** — Memory retrieval happens in background (~40ms)
- **Context injection** — Relevant memories injected directly into LLM prompt
- **Automatic fact extraction** — Server-side LLM extracts facts from conversations
- **Semantic search** — Find memories by meaning, not keywords
- **Circuit breaker** — Automatic failover on server unavailability

## Prerequisites

1. **Mem0 server running locally**:

   Using Docker:
   ```bash
   docker run -d -p 8000:8000 mem0ai/mem0:latest
   ```

   Or via Docker Compose with custom config:
   ```yaml
   version: "3.8"
   services:
     mem0:
       image: mem0ai/mem0:latest
       ports:
         - "8000:8000"
       environment:
         - MEM0_CONFIG_PATH=/app/config.yaml
       volumes:
         - ./mem0-config.yaml:/app/config.yaml
         - mem0_data:/app/data
   volumes:
     mem0_data:
   ```

2. **Verify server is reachable**:
   ```bash
   curl http://localhost:8000/health
   ```

   Your setup uses port 8889:
   ```bash
   curl http://10.0.0.150:8889/health
   ```

## Installation

From GitHub repository:
```bash
hermes plugins install https://github.com/yourusername/mem0-local-hermes-plugin.git
```

Or with shorthand:
```bash
hermes plugins install yourusername/mem0-local-hermes-plugin
```

From local directory (during development):
```bash
hermes plugins install /path/to/mem0-local-hermes-plugin
```

The installer will prompt for:
- `MEM0_BASE_URL` — Your local Mem0 server URL (default: `http://localhost:8000`)
- `MEM0_USER_ID` — User identifier for memory scoping (default: `hermes-user`)

## Configuration

The plugin supports two configuration methods that work together:

1. **Environment variables** (`~/.hermes/.env`) - Primary configuration
2. **Config file** (`~/.hermes/mem0-local.json`) - Optional overrides

**Precedence**: Config file values override environment variables. This allows you to set defaults in `.env` and override specific values in the JSON file.

### Method 1: Environment Variables (Recommended)

Set in `~/.hermes/.env`:

| Variable | Description | Default |
|----------|-------------|---------|
| `MEM0_BASE_URL` | Local Mem0 server URL | `http://localhost:8000` |
| `MEM0_USER_ID` | User identifier | `hermes-user` |
| `MEM0_AGENT_ID` | Agent identifier | `hermes` |

Example:
```env
MEM0_BASE_URL=http://10.0.0.150:8889
MEM0_USER_ID=henry_hofmann
MEM0_AGENT_ID=hermes
```

### Method 2: Config File (Optional Overrides)

Create `~/.hermes/mem0-local.json` to override specific settings:
```json
{
  "base_url": "http://10.0.0.150:8889",
  "user_id": "henry_hofmann",
  "agent_id": "hermes",
  "rerank": true,
  "timeout": 10.0
}
```

Example for your setup:
```json
{
  "base_url": "http://10.0.0.150:8889",
  "user_id": "henry_hofmann",
  "agent_id": "hermes",
  "rerank": true,
  "timeout": 10.0
}
```

## Usage

### Activate the Memory Provider

```bash
hermes memory mem0-local
```

### Restart Gateway

```bash
hermes gateway restart
```

### How It Works

1. **User message received** → `queue_prefetch()` spawns background thread
2. **Mem0 search** → Semantic search for relevant memories (~40ms)
3. **Context injection** → Results injected via `pre_llm_call` hook
4. **LLM receives** → User message + memory context (no tool call needed!)

**Example**:
```
User: "Hey, is a new episode out from my favorite anime?"

↓ [Background: mem0.prefetch() searches for "favorite anime"]

LLM receives:
"""
Hey, is a new episode out from my favorite anime?

## Mem0 Memory
- My favorite animes are Naruto, One Piece, and Demon Slayer (score: 0.87)
"""

Assistant: "Let me check for new episodes of Naruto, One Piece, and Demon Slayer..."
```

### Available Tools

The plugin also provides explicit memory tools:

| Tool | Description |
|------|-------------|
| `mem0_profile` | Retrieve all stored memories about the user |
| `mem0_search` | Search memories by semantic similarity |
| `mem0_conclude` | Store a fact verbatim (no LLM extraction) |

**Tool usage examples**:

```
# Get all memories
mem0_profile()

# Search with reranking
mem0_search(query="project deadlines", rerank=true, top_k=5)

# Store a fact explicitly
mem0_conclude(conclusion="I prefer Python over JavaScript for backend development")
```

## Circuit Breaker

After 5 consecutive API failures, the plugin pauses requests for 120 seconds to avoid hammering a down server. The breaker resets automatically.

## Troubleshooting

### "Mem0 server temporarily unavailable"

- Check server is running: `curl http://your-server:port/health`
- Verify `MEM0_BASE_URL` is correct
- Wait 2 minutes for circuit breaker to reset

### "No memories stored yet"

- Mem0 extracts facts automatically from conversations
- Or use `mem0_conclude` to store facts explicitly

### Memory not injected

- Check `is_available()` returns `True` in logs
- Verify `prefetch()` is being called (debug logs)
- Ensure Mem0 server has indexed memories
- Check network connectivity to your local server

### Connection issues

If your Mem0 server is on a different machine (like your 10.0.0.150):
- Ensure firewall allows connections on port 8889
- Verify the server binds to 0.0.0.0, not just localhost
- Check network routing between Hermes-Agent and Mem0 server

## Differences from Cloud Version

| Aspect | Cloud Version | Local Version |
|--------|--------------|---------------|
| **Client** | `mem0.MemoryClient(api_key=...)` | HTTP requests to local server |
| **Auth** | API key | None (local network) |
| **Config** | `MEM0_API_KEY` | `MEM0_BASE_URL` |
| **Latency** | Network-dependent | ~40ms (local) |
| **Privacy** | Cloud processing | Full local control |
| **Cost** | Pay-per-use | Free (self-hosted) |

## Development

For development, install from local path:
```bash
hermes plugins install /path/to/mem0-local-hermes-plugin
```

Watch for changes:
```bash
# In plugin directory
hermes gateway restart  # After each change
```

## License

MIT