# Troubleshooting Flynn

This guide covers common issues, error messages, and debugging techniques for Flynn.

## Table of Contents

- [Common Errors](#common-errors)
- [Model Issues](#model-issues)
- [Tool Issues](#tool-issues)
- [Channel Issues](#channel-issues)
- [Gateway Issues](#gateway-issues)
- [Configuration Issues](#configuration-issues)
- [Memory & Database Issues](#memory--database-issues)
- [Debug Mode](#debug-mode)
- [Getting Help](#getting-help)

## Common Errors

### `Error: Environment variable FLYNN_CONFIG is not set`

Flynn can't find your configuration file.

**Solution:**

```bash
# Create config from template
cp config/default.yaml ~/.config/flynn/config.yaml

# Or specify config file explicitly
flynn start --config ~/my-config.yaml
```

### `Error: Failed to load config: ...`

Configuration validation failed. Check your YAML syntax.

**Solution:**

```bash
# Validate your config
flynn doctor --config ~/.config/flynn/config.yaml

# Check YAML syntax
cat ~/.config/flynn/config.yaml | yamllint
```

Common issues:
- Missing quotes around special characters
- Incorrect indentation (YAML is space-sensitive, 2 spaces)
- Invalid boolean values (use `true`/`false`, not `yes`/`no`)

### `Error: Tool 'xxx' is not allowed by tool policy`

Tool execution blocked by policy configuration.

**Solution:**

1. Check tool policy in config:
   ```yaml
   tools:
     policy: 'full'  # or 'coding', 'messaging', 'minimal'
     profiles:
       full:
         allow: ['*']
         deny: []
   ```

2. Check agent-specific tool overrides:
   ```yaml
   agents:
     my-agent:
       toolPolicy: 'full'
   ```

3. Verify tool is registered (check `src/daemon/index.ts`)

### `Error: Session not found`

Gateway tried to access a non-existent session.

**Solution:**

```bash
# List active sessions
flynn sessions

# Sessions are auto-created on first message
# Ensure you're sending to a valid channel/sender combination
```

## Model Issues

### Model refuses to answer / "I can't help with that"

The model may be rejecting requests due to content filters or safety constraints.

**Solution:**

1. Try rephrasing your request
2. Check if the model has specific content policies
3. Try a different model tier:
   ```bash
   # In TUI, switch models
   /model complex
   ```

### Rate Limit Errors / Too Many Requests

API rate limits exceeded.

**Solution:**

1. Reduce request frequency
2. Add retry configuration in config:
   ```yaml
   models:
     default:
       anthropic:
         apiKey: 'sk-...'
         retry:
           maxAttempts: 3
           initialDelayMs: 1000
           maxDelayMs: 30000
           multiplier: 2
   ```

3. Switch to a different provider or tier

### Model Fallback Not Working

Fallback chain not triggering on errors.

**Solution:**

1. Check model router config:
   ```yaml
   models:
     router:
       tiers:
         default: 'anthropic:claude-sonnet-4-20250514'
         fallbackChain:
           - 'github:claude-sonnet-4-5'
           - 'local:ollama:llama3'
   ```

2. Check error patterns in retry config (errors matching these patterns won't retry):
   ```yaml
   retry:
     nonRetryablePatterns:
       - 'invalid_api_key'
       - 'permission_denied'
   ```

3. Enable debug logging to see fallback decisions:
   ```bash
   DEBUG='*' flynn start
   ```

### Context Window Exceeded

Conversation too long for model's context window.

**Solution:**

1. Check compaction settings:
   ```yaml
   agents:
     default:
       compaction:
         thresholdPct: 80
         keepTurns: 4
         summaryMaxTokens: 1024
   ```

2. Increase `keepTurns` to preserve more recent history
3. Increase `thresholdPct` to trigger compaction earlier

## Tool Issues

### Tool Execution Timeout

Tool took too long to complete.

**Solution:**

1. Check timeout config:
   ```yaml
   tools:
     executor:
       defaultTimeoutMs: 30000
   ```

2. Increase timeout for specific tools (if supported):
   ```bash
   shell.exec --timeout 60000 "long-running-command"
   ```

3. Check if tool is hanging (stuck process, network issue)

### Tool Permission Denied

Tool can't access file/execute command.

**Solution:**

1. Check file permissions:
   ```bash
   ls -la /path/to/file
   chmod +x /path/to/executable
   ```

2. Check Docker sandbox permissions (if enabled):
   ```bash
   # Ensure Docker daemon is running
   docker ps

   # Check Flynn's Docker access
   groups $USER | grep docker
   ```

3. Verify hook configuration (hooks may block tools):
   ```bash
   flynn config | grep -A 20 hooks
   ```

### Tool Output Truncated

Output exceeds maximum size limit.

**Solution:**

Check max output config:
```yaml
tools:
  executor:
    maxOutputBytes: 51200  # 50KB default
```

Increase limit if needed, or use file operations to handle large outputs.

### Tool Not Found

Tool doesn't exist or isn't registered.

**Solution:**

```bash
# List available tools
flynn doctor --config ~/.config/flynn/config.yaml

# Check if tool is in builtin list
grep -r "name: 'your.tool'" src/tools/builtin/
```

If you added a custom tool, ensure it's registered in `src/daemon/index.ts`.

## Channel Issues

### Telegram Bot Not Responding

Telegram bot not receiving or processing messages.

**Solution:**

1. Check bot token in config:
   ```yaml
   channels:
     telegram:
       enabled: true
       token: '123456789:ABCdefGHIjklMNOpqrSTUvwxYZ'
   ```

2. Verify bot is running:
   ```bash
   # Check Flynn logs for telegram startup
   flynn start 2>&1 | grep telegram
   ```

3. Test bot via Telegram API:
   ```bash
   curl https://api.telegram.org/bot<YOUR_TOKEN>/getMe
   ```

4. Check `allowed_chat_ids` whitelist:
   ```yaml
   channels:
     telegram:
       allowedChatIds: ['123456789']  # Your chat ID
   ```

### Discord Bot Not Joining Channels

Discord bot permissions issues.

**Solution:**

1. Check bot token:
   ```yaml
   channels:
     discord:
       enabled: true
       token: 'MTIzNDU2Nzg5O...ABcDefGhIjKlMnOpQrStUvWxYz'
   ```

2. Verify guild/channel IDs in whitelist:
   ```yaml
   channels:
     discord:
       allowedGuildIds: ['123456789012345678']
       allowedChannelIds: ['123456789012345678']
   ```

3. Check bot permissions in Discord server (need `Read Messages`, `Send Messages`, `Embed Links`)

### Slack Webhooks Not Receiving

Slack event subscription issues.

**Solution:**

1. Verify signing secret in config:
   ```yaml
   channels:
     slack:
       enabled: true
       signingSecret: 'a1b2c3d4e5f6g7h8i9j0k1l2m3n4o5p6'
   ```

2. Check Slack app permissions and event subscriptions
3. Verify ngrok/tunnel if testing locally

### WhatsApp Bot Not Connecting

WhatsApp Web.js connection issues.

**Solution:**

1. Check phone number whitelist:
   ```yaml
   channels:
     whatsapp:
       enabled: true
       allowedNumbers: ['+1234567890']
   ```

2. WhatsApp requires QR code scan on first run - run in foreground:
   ```bash
   flynn start  # Watch console for QR code
   ```

3. If running in Docker, ensure it can display QR code or use saved session

## Gateway Issues

### WebSocket Connection Refused

Can't connect to gateway WebSocket.

**Solution:**

1. Check gateway is running:
   ```bash
   curl http://localhost:18800/health
   ```

2. Check port configuration:
   ```yaml
   gateway:
     enabled: true
     port: 18800
   ```

3. Check firewall rules:
   ```bash
   sudo ufw allow 18800
   ```

4. Check auth token if configured:
   ```yaml
   gateway:
     auth:
       token: 'your-secret-token'
   ```

### Gateway Lock Active

Only one WebSocket client allowed at a time.

**Solution:**

```yaml
gateway:
  lock:
    enabled: false  # Disable lock
```

Or disconnect existing client first.

### Tailscale Serve Not Exposing

Tailscale integration not working.

**Solution:**

1. Ensure Tailscale is installed and running:
   ```bash
   tailscale status
   ```

2. Check Tailscale config:
   ```yaml
   gateway:
     tailscaleServe:
       enabled: true
       hostname: 'my-flynn'
       port: 443
   ```

3. Check Flynn logs for Tailscale errors:
   ```bash
   flynn start 2>&1 | grep -i tailscale
   ```

## Configuration Issues

### Invalid YAML Syntax

Configuration file has YAML syntax errors.

**Solution:**

```bash
# Validate with YAML linter
pip install yamllint
yamllint ~/.config/flynn/config.yaml

# Or use online YAML validator
# https://www.yamllint.com/
```

Common mistakes:
- Using tabs instead of spaces (YAML requires spaces)
- Incorrect indentation (must be consistent)
- Missing quotes around special characters (`:`, `{`, `}`, `[`, `]`)
- Unclosed brackets or quotes

### Environment Variable Expansion Not Working

`${ENV_VAR}` in config not expanding.

**Solution:**

1. Ensure variable is set:
   ```bash
   echo $MY_API_KEY
   ```

2. Check variable syntax in config:
   ```yaml
   models:
     default:
       anthropic:
         apiKey: '${ANTHROPIC_API_KEY}'  # Correct
         # Not: $ANTHROPIC_API_KEY or "${ANTHROPIC_API_KEY}"
   ```

3. Ensure no quotes around the entire value:
   ```yaml
   # Wrong
   apiKey: '${ANTHROPIC_API_KEY}'

   # Correct
   apiKey: '${ANTHROPIC_API_KEY}'
   ```

### Secrets Showing in Logs

API keys or sensitive data visible in logs.

**Solution:**

Flynn automatically redacts secrets when showing config with `flynn config`.

If you see secrets in output, check:
- Don't log config manually (use the built-in redaction)
- Don't commit config files to git (add to `.gitignore`)
- Use `FLYNN_CONFIG` env var for sensitive paths

## Memory & Database Issues

### SQLite Database Locked

Can't write to session or vector database.

**Solution:**

1. Check if another Flynn instance is running:
   ```bash
   ps aux | grep flynn
   ```

2. Kill existing instances:
   ```bash
   pkill flynn
   ```

3. Check database permissions:
   ```bash
   ls -la ~/.local/share/flynn/*.db
   chmod 644 ~/.local/share/flynn/*.db
   ```

### Memory Not Saving

Memory writes not persisting.

**Solution:**

1. Check memory directory:
   ```bash
   ls -la ~/.local/share/flynn/memory/
   ```

2. Check namespace format (must be valid filename):
   ```bash
   # Good
   memory.write --namespace 'my-knowledge'

   # Bad
   memory.write --namespace 'my/namespace'  # Creates directory
   ```

3. Check disk space:
   ```bash
   df -h ~/.local/share/flynn/
   ```

### Vector Search Returns No Results

Hybrid search not finding matches.

**Solution:**

1. Ensure embeddings are generated:
   ```bash
   # Check vector database
   sqlite3 ~/.local/share/flynn/vectors.db "SELECT COUNT(*) FROM embeddings;"
   ```

2. Check embedding provider config:
   ```yaml
   memory:
     embeddings:
       provider: 'openai'  # or 'gemini', 'ollama', 'llamacpp'
       openai:
         apiKey: '${OPENAI_API_KEY}'
         model: 'text-embedding-3-small'
   ```

3. Try keyword search only:
   ```bash
   memory.search --query 'my query' --keyword-only
   ```

## Debug Mode

### Enable Debug Logging

Flynn uses console logging. Enable verbose output:

```bash
# Set DEBUG environment variable (if using debug packages)
DEBUG='*' flynn start

# Or redirect all output to file
flynn start > /tmp/flynn.log 2>&1

# Monitor logs in real-time
tail -f /tmp/flynn.log
```

### Run Doctor Command

Use the built-in diagnostic tool:

```bash
# Full check
flynn doctor

# Check specific component
flynn doctor --config ~/.config/flynn/config.yaml

# Check connectivity
flynn doctor --check connectivity
```

The doctor checks:
- Config syntax and validation
- Model provider connectivity
- Channel adapter status
- Memory and database integrity
- Gateway health

### Test Components Individually

```bash
# Test model connectivity
flynn send "Hello, world!"

# Test specific tool (in TUI)
/file.read /path/to/file

# Test channel
# Send message via platform (Telegram, Discord, etc.)

# Test gateway
curl http://localhost:18800/health
```

### Inspect Session Data

```bash
# View sessions
flynn sessions

# Inspect session database directly
sqlite3 ~/.local/share/flynn/sessions.db "SELECT * FROM sessions LIMIT 5;"

# View session messages
sqlite3 ~/.local/share/flynn/sessions.db "SELECT * FROM messages WHERE session_id = '...';"
```

### Enable Heartbeat Monitoring

Flynn includes a heartbeat monitor that checks system health:

```yaml
automation:
  heartbeat:
    enabled: true
    interval: '5m'
    checks:
      - 'gateway'
      - 'model'
      - 'channels'
      - 'memory'
      - 'disk'
```

Failures will be logged and notifications sent (if configured).

## Getting Help

### Log Your Issue

When reporting issues, include:

1. **Error message** (full stack trace if available)
2. **Flynn version**: `flynn --version`
3. **Configuration** (redact secrets): `flynn config`
4. **Node version**: `node --version`
5. **OS**: `uname -a`
6. **Steps to reproduce**

### Check Existing Issues

Search GitHub issues for similar problems:
- https://github.com/your-repo/flynn/issues

### Ask for Help

- **GitHub Issues**: Bug reports and feature requests
- **GitHub Discussions**: Questions and community help
- **Documentation**: Check README.md, AGENTS.md, and this file

### Provide Diagnostic Output

```bash
# Run doctor and save output
flynn doctor > /tmp/flynn-doctor.txt 2>&1

# Get config (redacted)
flynn config > /tmp/flynn-config.txt

# Get logs
journalctl -u flynn -n 100 --no-pager > /tmp/flynn-logs.txt

# Attach these files to your issue
```

---

Still having issues? Open a GitHub issue with the diagnostic output above.