Add Discord setup documentation (#29)

- Create docs/discord-setup.md with full setup guide
- Update README to include Discord in channel list
- Add Discord to network architecture table

README.md

@@ -1,12 +1,12 @@
 # LettaBot
 
-Your personal AI assistant that remembers everything across **Telegram, Slack, WhatsApp, and Signal**. Powered by the [Letta Code SDK](https://github.com/letta-ai/letta-code-sdk).
+Your personal AI assistant that remembers everything across **Telegram, Slack, Discord, WhatsApp, and Signal**. Powered by the [Letta Code SDK](https://github.com/letta-ai/letta-code-sdk).
 
 <img width="750" alt="lettabot-preview" src="https://github.com/user-attachments/assets/9f01b845-d5b0-447b-927d-ae15f9ec7511" />
 
 ## Features
 
-- **Multi-Channel** - Chat seamlessly across Telegram, Slack, WhatsApp, and Signal
+- **Multi-Channel** - Chat seamlessly across Telegram, Slack, Discord, WhatsApp, and Signal
 - **Unified Memory** - Single agent remembers everything from all channels
 - **Persistent Memory** - Agent remembers conversations across sessions (days/weeks/months)
 - **Local Tool Execution** - Agent can read files, search code, run commands on your machine
@@ -129,9 +129,10 @@ LettaBot uses a **single agent with a single conversation** across all channels:
 
 ```
 Telegram ──┐
-           ├──→ ONE AGENT ──→ ONE CONVERSATION
+Slack ─────┤
-Slack ─────┤    (memory)      (chat history)
+Discord ───┼──→ ONE AGENT ──→ ONE CONVERSATION
-WhatsApp ──┘
+WhatsApp ──┤    (memory)      (chat history)
+Signal ────┘
 ```
 
 - Start a conversation on Telegram
@@ -143,6 +144,7 @@ WhatsApp ──┘
 |---------|-------|--------------|
 | Telegram | [Setup Guide](docs/getting-started.md) | Bot token from @BotFather |
 | Slack | [Setup Guide](docs/slack-setup.md) | Slack app with Socket Mode |
+| Discord | [Setup Guide](docs/discord-setup.md) | Discord bot + Message Content Intent |
 | WhatsApp | [Setup Guide](docs/whatsapp-setup.md) | Phone with WhatsApp |
 | Signal | [Setup Guide](docs/signal-setup.md) | signal-cli + phone number |
 
@@ -172,6 +174,7 @@ letta --agent <agent_id>
 |---------|-----------------|---------------|
 | Telegram | Long-polling (outbound HTTP) | None |
 | Slack | Socket Mode (outbound WebSocket) | None |
+| Discord | Gateway (outbound WebSocket) | None |
 | WhatsApp | Outbound WebSocket via Baileys | None |
 | Signal | Local daemon on 127.0.0.1 | None |
 
@@ -235,6 +238,7 @@ lettabot destroy
 
 - [Getting Started](docs/getting-started.md)
 - [Slack Setup](docs/slack-setup.md)
+- [Discord Setup](docs/discord-setup.md)
 - [WhatsApp Setup](docs/whatsapp-setup.md)
 - [Signal Setup](docs/signal-setup.md)
 

docs/discord-setup.md

@@ -0,0 +1,208 @@
+# Discord Setup for LettaBot
+
+This guide walks you through setting up Discord as a channel for LettaBot.
+
+## Overview
+
+LettaBot connects to Discord using a **Bot Application** with the Gateway API:
+- No public URL required (uses WebSocket connection)
+- Works behind firewalls
+- Real-time bidirectional communication
+
+## Prerequisites
+
+- A Discord server where you have permission to add bots
+- LettaBot installed and configured with at least `LETTA_API_KEY`
+
+## Step 1: Create a Discord Application
+
+1. Go to **https://discord.com/developers/applications**
+2. Click **"New Application"**
+3. Enter a name (e.g., `LettaBot`)
+4. Click **"Create"**
+
+## Step 2: Create the Bot
+
+1. In the left sidebar, click **"Bot"**
+2. Click **"Reset Token"** (or "Add Bot" if this is new)
+3. **Copy the token** - this is your `DISCORD_BOT_TOKEN`
+
+   > **Important**: You can only see this token once. If you lose it, you'll need to reset it.
+
+## Step 3: Enable Message Content Intent
+
+This is required for the bot to read message content.
+
+1. Still in the **"Bot"** section
+2. Scroll down to **"Privileged Gateway Intents"**
+3. Enable **"MESSAGE CONTENT INTENT"**
+4. Click **"Save Changes"**
+
+## Step 4: Generate Invite URL
+
+1. In the left sidebar, go to **"OAuth2"** → **"URL Generator"**
+2. Under **"Scopes"**, select:
+   - `bot`
+3. Under **"Bot Permissions"**, select:
+   - `Send Messages`
+   - `Read Message History`
+   - `View Channels`
+4. Copy the generated URL at the bottom
+
+Or use this URL template (replace `YOUR_CLIENT_ID`):
+```
+https://discord.com/oauth2/authorize?client_id=YOUR_CLIENT_ID&permissions=68608&scope=bot
+```
+
+> **Tip**: Your Client ID is in **"General Information"** or in the URL when viewing your app.
+
+## Step 5: Add Bot to Your Server
+
+1. Open the invite URL from Step 4 in your browser
+2. Select the server you want to add the bot to
+3. Click **"Authorize"**
+4. Complete the CAPTCHA if prompted
+
+You should see `[Bot Name] has joined the server` in Discord.
+
+## Step 6: Configure LettaBot
+
+Run the onboarding wizard and select Discord:
+
+```bash
+lettabot onboard
+```
+
+Or add directly to your `lettabot.yaml`:
+
+```yaml
+channels:
+  discord:
+    enabled: true
+    token: "your-bot-token-here"
+    dmPolicy: pairing  # or 'allowlist' or 'open'
+```
+
+## Step 7: Start LettaBot
+
+```bash
+lettabot server
+```
+
+You should see:
+```
+Registered channel: Discord
+[Discord] Connecting...
+[Discord] Bot logged in as YourBot#1234
+[Discord] DM policy: pairing
+```
+
+## Step 8: Test the Integration
+
+### In a Server Channel
+1. Go to a text channel in your Discord server
+2. Type `@YourBot hello!`
+3. The bot should respond
+
+### Direct Message
+1. Right-click on the bot in the server member list
+2. Click **"Message"**
+3. Send a message: `Hello!`
+4. The bot should respond (may require pairing approval first)
+
+## Access Control
+
+LettaBot supports three DM policies for Discord:
+
+### Pairing (Recommended)
+```yaml
+dmPolicy: pairing
+```
+- New users receive a pairing code
+- Approve with: `lettabot pairing approve discord <CODE>`
+- Most secure for personal use
+
+### Allowlist
+```yaml
+dmPolicy: allowlist
+allowedUsers:
+  - "123456789012345678"  # Discord user IDs
+```
+- Only specified users can interact
+- Find user IDs: Enable Developer Mode in Discord settings, then right-click a user → "Copy User ID"
+
+### Open
+```yaml
+dmPolicy: open
+```
+- Anyone can message the bot
+- Not recommended for personal bots
+
+## Adding Reactions
+
+LettaBot can react to messages using the `lettabot-react` CLI:
+
+```bash
+# React to the most recent message
+lettabot-react add --emoji ":eyes:"
+
+# React to a specific message
+lettabot-react add --emoji ":thumbsup:" --channel discord --chat 123456789 --message 987654321
+```
+
+## Troubleshooting
+
+### Bot shows as offline
+
+1. Make sure LettaBot is running (`lettabot server`)
+2. Check for errors in the console
+3. Verify your bot token is correct
+
+### Bot doesn't respond to messages
+
+1. **Check MESSAGE CONTENT INTENT** is enabled:
+   - Discord Developer Portal → Your App → Bot → Privileged Gateway Intents
+   - Toggle ON "MESSAGE CONTENT INTENT"
+
+2. **Check bot has permissions** in the channel:
+   - Server Settings → Roles → Your Bot's Role
+   - Or check channel-specific permissions
+
+3. **Check pairing status** if using pairing mode:
+   - New users need to be approved via `lettabot pairing list`
+
+### "0 Servers" in Developer Portal
+
+The bot hasn't been invited to any servers yet. Use the invite URL from Step 4.
+
+### Bot can't DM users
+
+Discord bots can only DM users who:
+- Share a server with the bot, OR
+- Have previously DM'd the bot
+
+This is a Discord limitation, not a LettaBot issue.
+
+### Rate limiting
+
+If the bot stops responding temporarily, it may be rate-limited by Discord. Wait a few minutes and try again. Avoid sending many messages in quick succession.
+
+## Security Notes
+
+- **Bot tokens** should be kept secret - never commit them to git
+- Use `dmPolicy: pairing` or `allowlist` in production
+- The bot can only see messages in channels it has access to
+- DMs are only visible between the bot and that specific user
+
+## Cross-Channel Memory
+
+Since LettaBot uses a single agent across all channels:
+- Messages you send on Discord continue the same conversation as Telegram/Slack
+- The agent remembers context from all channels
+- You can start a conversation on Telegram and continue it on Discord
+
+## Next Steps
+
+- [Slack Setup](./slack-setup.md)
+- [WhatsApp Setup](./whatsapp-setup.md)
+- [Signal Setup](./signal-setup.md)