# Matrix-Letta Bridge

A bridge connecting [Letta](https://letta.com) AI agents to encrypted Matrix rooms using [mautrix-python](https://github.com/mautrix/python).

## Features

- **End-to-end encryption (E2EE)** - Full support via mautrix-python's OlmMachine
- **Reaction-to-feedback mapping** - Matrix emoji reactions (thumbs up/down) are sent as feedback to Letta for preference learning
- **Persistent crypto store** - SQLite-based storage for E2EE keys and session state
- **Cross-signing support** - Optional recovery key for device verification

## Setup

### Prerequisites

- Python 3.10+
- A Matrix homeserver account
- A Letta Cloud account and agent

### Installation

```bash
python -m venv venv
source venv/bin/activate
pip install mautrix python-dotenv requests
```

### Configuration

Create a `.env` file:

```bash
# Matrix
MATRIX_HOMESERVER=https://your-homeserver.example.com
MATRIX_USER_ID=@bot:your-homeserver.example.com
MATRIX_PASSWORD=your-bot-password
MATRIX_RECOVERY_KEY=  # Optional: for cross-signing verification

# Letta
LETTA_API_KEY=sk-let-...
LETTA_AGENT_ID=agent-...
LETTA_BASE_URL=https://api.letta.com/v1/

# Optional
BRIDGE_DB_URL=sqlite:store/bridge.db
CRYPTO_PICKLE_KEY=your-pickle-key
```

### Running

```bash
python bridge-e2ee.py
```

Or install as a systemd service using `meridian-bridge.service`.

## Reaction Feedback Mapping

| Reaction | Feedback |
|----------|----------|
| 👍 👍️ ❤️ 🎉 ✅ 🙌 💯 | positive |
| 👎 👎️ 👀 ❓ 😕 ❌ | negative |

Feedback is sent to Letta's `/v1/steps/{step_id}/feedback` endpoint via PATCH.

## Architecture

- `bridge-e2ee.py` - Main bridge script
- `sqlite_crypto_store.py` - E2EE key storage implementation
- `store/` - Runtime data (SQLite databases, session state)

## License

MIT