From 9ef9fff2b0c3f1a44b62bf1a246795dfc710530a Mon Sep 17 00:00:00 2001
From: Chris Coutinho <chris@coutinho.io>
Date: Mon, 13 Oct 2025 18:08:01 +0200
Subject: [PATCH] docs: Update Docs

---
 docs/running.md         | 440 +++++++++++++++++++++++++++++++++
 docs/troubleshooting.md | 531 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 971 insertions(+)
 create mode 100644 docs/running.md
 create mode 100644 docs/troubleshooting.md

diff --git a/docs/running.md b/docs/running.md
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+# Running the Server
+
+This guide covers different ways to start and run the Nextcloud MCP server.
+
+## Prerequisites
+
+Before running the server:
+
+1. **Install the server** - See [Installation Guide](installation.md)
+2. **Configure environment** - See [Configuration Guide](configuration.md)
+3. **Set up authentication** - See [OAuth Setup](oauth-setup.md) or [Authentication](authentication.md)
+
+---
+
+## Quick Start
+
+Load your environment variables and start the server:
+
+```bash
+# Load environment variables from .env
+export $(grep -v '^#' .env | xargs)
+
+# Start the server
+uv run nextcloud-mcp-server
+```
+
+The server will start on `http://127.0.0.1:8000` by default.
+
+---
+
+## Running Locally
+
+### Method 1: Using nextcloud-mcp-server CLI (Recommended)
+
+The CLI provides a simple interface with built-in defaults:
+
+#### OAuth Mode
+
+```bash
+# Auto-detected when NEXTCLOUD_USERNAME/PASSWORD not set
+uv run nextcloud-mcp-server
+
+# Explicitly force OAuth mode
+uv run nextcloud-mcp-server --oauth
+
+# OAuth with custom host and port
+uv run nextcloud-mcp-server --oauth --host 0.0.0.0 --port 8080
+
+# OAuth with pre-configured client
+uv run nextcloud-mcp-server --oauth \
+  --oauth-client-id abc123 \
+  --oauth-client-secret xyz789
+
+# OAuth with specific apps only
+uv run nextcloud-mcp-server --oauth \
+  --enable-app notes \
+  --enable-app calendar
+```
+
+#### BasicAuth Mode (Legacy)
+
+```bash
+# Auto-detected when NEXTCLOUD_USERNAME/PASSWORD are set
+uv run nextcloud-mcp-server
+
+# Explicitly force BasicAuth mode
+uv run nextcloud-mcp-server --no-oauth
+
+# BasicAuth with specific apps
+uv run nextcloud-mcp-server --no-oauth \
+  --enable-app notes \
+  --enable-app webdav
+```
+
+### Method 2: Using uvicorn
+
+For more control over server options (workers, reload, etc.):
+
+```bash
+# Load environment variables
+export $(grep -v '^#' .env | xargs)
+
+# Run with uvicorn
+uv run uvicorn nextcloud_mcp_server.app:get_app \
+  --factory \
+  --host 127.0.0.1 \
+  --port 8000 \
+  --reload  # Enable auto-reload for development
+```
+
+See all uvicorn options at [https://www.uvicorn.org/settings/](https://www.uvicorn.org/settings/)
+
+### Method 3: Using Python Module
+
+```bash
+# Load environment variables
+export $(grep -v '^#' .env | xargs)
+
+# Run as Python module
+python -m nextcloud_mcp_server.app --oauth --port 8000
+```
+
+---
+
+## Running with Docker
+
+### Basic Docker Run
+
+```bash
+# OAuth mode
+docker run -p 127.0.0.1:8000:8000 --env-file .env --rm \
+  ghcr.io/cbcoutinho/nextcloud-mcp-server:latest --oauth
+
+# BasicAuth mode
+docker run -p 127.0.0.1:8000:8000 --env-file .env --rm \
+  ghcr.io/cbcoutinho/nextcloud-mcp-server:latest
+```
+
+### Docker with Persistent OAuth Storage
+
+```bash
+docker run -p 127.0.0.1:8000:8000 --env-file .env \
+  -v $(pwd)/.oauth:/app/.oauth \
+  --rm ghcr.io/cbcoutinho/nextcloud-mcp-server:latest --oauth
+```
+
+### Docker Compose
+
+Create `docker-compose.yml`:
+
+```yaml
+version: '3.8'
+
+services:
+  mcp:
+    image: ghcr.io/cbcoutinho/nextcloud-mcp-server:latest
+    command: --oauth --enable-app notes --enable-app calendar
+    ports:
+      - "127.0.0.1:8000:8000"
+    env_file:
+      - .env
+    volumes:
+      - ./oauth-storage:/app/.oauth
+    restart: unless-stopped
+```
+
+Start the service:
+
+```bash
+# Start in foreground
+docker-compose up
+
+# Start in background
+docker-compose up -d
+
+# View logs
+docker-compose logs -f
+
+# Stop the service
+docker-compose down
+```
+
+---
+
+## Server Options
+
+### Host and Port
+
+```bash
+# Bind to all interfaces (accessible from network)
+uv run nextcloud-mcp-server --host 0.0.0.0 --port 8000
+
+# Bind to localhost only (default, more secure)
+uv run nextcloud-mcp-server --host 127.0.0.1 --port 8000
+
+# Use a different port
+uv run nextcloud-mcp-server --port 8080
+```
+
+**Security Note:** Using `--host 0.0.0.0` exposes the server to your network. Only use this if you understand the security implications.
+
+### Transport Protocols
+
+The server supports multiple MCP transport protocols:
+
+```bash
+# Streamable HTTP (recommended)
+uv run nextcloud-mcp-server --transport streamable-http
+
+# SSE - Server-Sent Events (default, deprecated)
+uv run nextcloud-mcp-server --transport sse
+
+# HTTP
+uv run nextcloud-mcp-server --transport http
+```
+
+> [!WARNING]
+> SSE transport is deprecated and will be removed in a future version of the MCP spec. Please migrate to `streamable-http`.
+
+### Logging
+
+```bash
+# Set log level (critical, error, warning, info, debug, trace)
+uv run nextcloud-mcp-server --log-level debug
+
+# Production: use warning or error
+uv run nextcloud-mcp-server --log-level warning
+```
+
+### Selective App Enablement
+
+By default, all supported Nextcloud apps are enabled. You can enable specific apps only:
+
+```bash
+# Available apps: notes, tables, webdav, calendar, contacts, deck
+
+# Enable all apps (default)
+uv run nextcloud-mcp-server
+
+# Enable only Notes
+uv run nextcloud-mcp-server --enable-app notes
+
+# Enable multiple apps
+uv run nextcloud-mcp-server \
+  --enable-app notes \
+  --enable-app calendar \
+  --enable-app contacts
+
+# Enable only WebDAV for file operations
+uv run nextcloud-mcp-server --enable-app webdav
+```
+
+**Use cases:**
+- Reduce memory usage and startup time
+- Limit functionality for security/organizational reasons
+- Test specific app integrations
+- Run lightweight instances with only needed features
+
+---
+
+## Development Mode
+
+For active development with auto-reload:
+
+```bash
+# Using uvicorn with reload
+uv run uvicorn nextcloud_mcp_server.app:get_app \
+  --factory \
+  --reload \
+  --host 127.0.0.1 \
+  --port 8000 \
+  --log-level debug
+```
+
+Or use the CLI with reload flag:
+
+```bash
+uv run nextcloud-mcp-server --reload --log-level debug
+```
+
+---
+
+## Connecting to the Server
+
+### Using MCP Inspector
+
+MCP Inspector is a browser-based tool for testing MCP servers:
+
+```bash
+# Start MCP Inspector
+uv run mcp dev
+
+# In the browser:
+# 1. Enter server URL: http://localhost:8000
+# 2. Complete OAuth flow (if using OAuth)
+# 3. Explore tools and resources
+```
+
+### Using MCP Clients
+
+MCP clients (like Claude Desktop, LLM IDEs) can connect to your server:
+
+1. Configure the client with your server URL
+2. Complete OAuth authentication (if enabled)
+3. Start interacting with Nextcloud through the LLM
+
+---
+
+## Verifying Server Status
+
+### Check Server Health
+
+```bash
+# Test if server is responding
+curl http://localhost:8000/health
+
+# Expected response: HTTP 200 OK
+```
+
+### Check OAuth Configuration
+
+Look for these log messages on startup:
+
+**OAuth mode:**
+```
+INFO     OAuth mode detected (NEXTCLOUD_USERNAME/PASSWORD not set)
+INFO     Configuring MCP server for OAuth mode
+INFO     OIDC discovery successful
+INFO     OAuth client ready: <client-id>...
+INFO     OAuth initialization complete
+```
+
+**BasicAuth mode:**
+```
+INFO     BasicAuth mode detected (NEXTCLOUD_USERNAME/PASSWORD set)
+INFO     Initializing Nextcloud client with BasicAuth
+```
+
+---
+
+## Process Management
+
+### Running as a Background Service
+
+#### Using systemd (Linux)
+
+Create `/etc/systemd/system/nextcloud-mcp.service`:
+
+```ini
+[Unit]
+Description=Nextcloud MCP Server
+After=network.target
+
+[Service]
+Type=simple
+User=your-user
+WorkingDirectory=/path/to/nextcloud-mcp-server
+EnvironmentFile=/path/to/.env
+ExecStart=/path/to/uv run nextcloud-mcp-server --oauth
+Restart=on-failure
+RestartSec=10
+
+[Install]
+WantedBy=multi-user.target
+```
+
+Enable and start:
+
+```bash
+sudo systemctl daemon-reload
+sudo systemctl enable nextcloud-mcp
+sudo systemctl start nextcloud-mcp
+sudo systemctl status nextcloud-mcp
+```
+
+#### Using Docker Compose
+
+See [Docker Compose section](#docker-compose) above - includes `restart: unless-stopped`.
+
+### Monitoring Logs
+
+```bash
+# Local installation with systemd
+sudo journalctl -u nextcloud-mcp -f
+
+# Docker
+docker logs -f <container-name>
+
+# Docker Compose
+docker-compose logs -f mcp
+```
+
+---
+
+## Performance Tuning
+
+### Multiple Workers
+
+For production deployments with higher load:
+
+```bash
+# Using CLI (if supported)
+uv run nextcloud-mcp-server --workers 4
+
+# Using uvicorn
+uv run uvicorn nextcloud_mcp_server.app:get_app \
+  --factory \
+  --workers 4 \
+  --host 0.0.0.0 \
+  --port 8000
+```
+
+### Production Settings
+
+```bash
+# Recommended production configuration
+uv run nextcloud-mcp-server \
+  --oauth \
+  --host 127.0.0.1 \
+  --port 8000 \
+  --log-level warning \
+  --transport streamable-http \
+  --workers 2
+```
+
+---
+
+## Troubleshooting
+
+### Server won't start
+
+Check logs for errors:
+```bash
+uv run nextcloud-mcp-server --log-level debug
+```
+
+Common issues:
+- Environment variables not loaded - See [Configuration](configuration.md#loading-environment-variables)
+- Port already in use - Try a different port with `--port`
+- OAuth configuration errors - See [Troubleshooting](troubleshooting.md)
+
+### Can't connect to server
+
+1. Verify server is running: `curl http://localhost:8000/health`
+2. Check firewall settings
+3. Verify host binding (use `0.0.0.0` to allow network access)
+4. Check OAuth authentication if enabled
+
+### OAuth authentication fails
+
+See [Troubleshooting OAuth](troubleshooting.md) for detailed OAuth troubleshooting.
+
+---
+
+## See Also
+
+- [Configuration Guide](configuration.md) - Environment variables
+- [OAuth Setup](oauth-setup.md) - OAuth authentication setup
+- [Troubleshooting](troubleshooting.md) - Common issues and solutions
+- [Installation](installation.md) - Installing the server
diff --git a/docs/troubleshooting.md b/docs/troubleshooting.md
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+# Troubleshooting
+
+This guide covers common issues and solutions for the Nextcloud MCP server.
+
+## OAuth Issues
+
+### Issue: "OAuth mode requires NEXTCLOUD_HOST environment variable"
+
+**Cause:** The `NEXTCLOUD_HOST` environment variable is not set or empty.
+
+**Solution:**
+
+```bash
+# Ensure NEXTCLOUD_HOST is set in your .env file
+echo "NEXTCLOUD_HOST=https://your.nextcloud.instance.com" >> .env
+
+# Load environment variables
+export $(grep -v '^#' .env | xargs)
+
+# Verify it's set
+echo $NEXTCLOUD_HOST
+```
+
+---
+
+### Issue: "OAuth mode requires either client credentials OR dynamic client registration"
+
+**Cause:** The Nextcloud OIDC app either:
+1. Is not installed
+2. Doesn't have dynamic client registration enabled
+3. Isn't providing a registration endpoint
+
+**Solution:**
+
+**Option 1: Enable dynamic client registration**
+
+1. Verify OIDC app is installed:
+   - Navigate to Nextcloud **Apps** → **Security**
+   - Install "OpenID Connect user backend" if not present
+
+2. Enable dynamic client registration:
+   - Go to **Settings** → **OIDC** (Administration)
+   - Enable "Allow dynamic client registration"
+
+3. Verify the registration endpoint exists:
+   ```bash
+   curl https://your.nextcloud.instance.com/.well-known/openid-configuration | jq '.registration_endpoint'
+   # Should output: "https://your.nextcloud.instance.com/apps/oidc/register"
+   ```
+
+**Option 2: Provide pre-configured credentials**
+
+Register a client and add credentials to `.env`:
+
+```bash
+# On your Nextcloud server
+php occ oidc:create \
+  --name="Nextcloud MCP Server" \
+  --type=confidential \
+  --redirect-uri="http://localhost:8000/oauth/callback"
+
+# Add to .env
+echo "NEXTCLOUD_OIDC_CLIENT_ID=<from-output>" >> .env
+echo "NEXTCLOUD_OIDC_CLIENT_SECRET=<from-output>" >> .env
+```
+
+See [OAuth Setup Guide](oauth-setup.md) for detailed instructions.
+
+---
+
+### Issue: "Stored client has expired"
+
+**Cause:** Dynamically registered OAuth clients expire (default: 1 hour).
+
+**Solution:**
+
+**Option 1: Restart the server** (automatic re-registration)
+
+```bash
+# Server checks credentials at startup and re-registers if expired
+uv run nextcloud-mcp-server --oauth
+```
+
+**Option 2: Use pre-configured credentials** (recommended for production)
+
+```bash
+# Register permanent client via Nextcloud CLI
+php occ oidc:create \
+  --name="Nextcloud MCP Server" \
+  --type=confidential \
+  --redirect-uri="http://localhost:8000/oauth/callback"
+
+# Add to .env
+NEXTCLOUD_OIDC_CLIENT_ID=<from-output>
+NEXTCLOUD_OIDC_CLIENT_SECRET=<from-output>
+```
+
+**Option 3: Increase expiration time**
+
+```bash
+# Via Nextcloud occ command (default: 3600 seconds)
+php occ config:app:set oidc expire_time --value "86400"  # 24 hours
+```
+
+---
+
+### Issue: "HTTP 401 Unauthorized" when calling Nextcloud APIs
+
+**Cause:** OAuth Bearer tokens may not work with certain Nextcloud endpoints due to session handling in the CORS middleware.
+
+**Background:** The `user_oidc` app's CORS middleware interferes with Bearer token authentication for non-OCS endpoints (like Notes API). This affects app-specific APIs but not OCS APIs.
+
+**Solution:**
+
+A patch for the `user_oidc` app is required to fix Bearer token support. See [oauth2-bearer-token-session-issue.md](oauth2-bearer-token-session-issue.md) for:
+- Detailed explanation of the issue
+- Patch to apply to the `user_oidc` app
+- Link to upstream pull request
+
+**Affected endpoints:**
+- Notes API (`/apps/notes/api/`)
+- Other app-specific endpoints
+
+**Unaffected endpoints:**
+- OCS APIs (`/ocs/v2.php/`)
+- Capabilities endpoint
+
+---
+
+### Issue: "Permission denied" when reading/writing OAuth client credentials file
+
+**Cause:** The server cannot access the OAuth client storage file (default: `.nextcloud_oauth_client.json`).
+
+**Solution:**
+
+```bash
+# Check file permissions
+ls -la .nextcloud_oauth_client.json
+
+# Fix file permissions (should be 0600 - owner read/write only)
+chmod 600 .nextcloud_oauth_client.json
+
+# Ensure the directory is writable
+chmod 755 $(dirname .nextcloud_oauth_client.json)
+
+# If the file doesn't exist, ensure the directory is writable so it can be created
+mkdir -p $(dirname .nextcloud_oauth_client.json)
+```
+
+---
+
+### Issue: "OIDC discovery failed" or "Cannot reach OIDC discovery endpoint"
+
+**Cause:** The server cannot reach the Nextcloud OIDC discovery endpoint.
+
+**Solution:**
+
+1. Verify the Nextcloud URL is correct:
+   ```bash
+   echo $NEXTCLOUD_HOST
+   # Should be the full URL: https://your.nextcloud.instance.com
+   ```
+
+2. Test the discovery endpoint manually:
+   ```bash
+   curl https://your.nextcloud.instance.com/.well-known/openid-configuration
+   # Should return JSON with OIDC configuration
+   ```
+
+3. Check network connectivity:
+   ```bash
+   ping your.nextcloud.instance.com
+   ```
+
+4. Verify OIDC app is installed and enabled in Nextcloud
+
+5. Check firewall rules if using Docker
+
+---
+
+### Switching Between OAuth and BasicAuth
+
+#### To switch from BasicAuth to OAuth:
+
+```bash
+# 1. Remove or comment out USERNAME/PASSWORD in .env
+sed -i 's/^NEXTCLOUD_USERNAME/#NEXTCLOUD_USERNAME/' .env
+sed -i 's/^NEXTCLOUD_PASSWORD/#NEXTCLOUD_PASSWORD/' .env
+
+# 2. Ensure NEXTCLOUD_HOST is set
+grep NEXTCLOUD_HOST .env
+
+# 3. Restart server with OAuth
+export $(grep -v '^#' .env | xargs)
+uv run nextcloud-mcp-server --oauth
+```
+
+#### To switch from OAuth to BasicAuth:
+
+```bash
+# 1. Add USERNAME/PASSWORD to .env
+echo "NEXTCLOUD_USERNAME=your-username" >> .env
+echo "NEXTCLOUD_PASSWORD=your-password" >> .env
+
+# 2. Restart server (BasicAuth auto-detected, or use --no-oauth)
+export $(grep -v '^#' .env | xargs)
+uv run nextcloud-mcp-server --no-oauth
+```
+
+---
+
+## Configuration Issues
+
+### Issue: Environment variables not loaded
+
+**Cause:** Environment variables from `.env` file are not loaded into the shell.
+
+**Solution:**
+
+**On Linux/macOS:**
+```bash
+# Load all variables from .env
+export $(grep -v '^#' .env | xargs)
+
+# Verify variables are set
+env | grep NEXTCLOUD
+```
+
+**On Windows (PowerShell):**
+```powershell
+# Load variables from .env
+Get-Content .env | ForEach-Object {
+    if ($_ -match '^\s*([^#][^=]*)\s*=\s*(.*)$') {
+        [Environment]::SetEnvironmentVariable($matches[1].Trim(), $matches[2].Trim(), "Process")
+    }
+}
+
+# Verify variables are set
+Get-ChildItem Env:NEXTCLOUD*
+```
+
+**With Docker:**
+```bash
+# Docker automatically loads .env when using --env-file
+docker run -p 127.0.0.1:8000:8000 --env-file .env --rm \
+  ghcr.io/cbcoutinho/nextcloud-mcp-server:latest
+```
+
+---
+
+### Issue: ".env file not found"
+
+**Cause:** The `.env` file doesn't exist or is in the wrong location.
+
+**Solution:**
+
+```bash
+# Create .env from sample
+cp env.sample .env
+
+# Edit with your Nextcloud details
+nano .env  # or vim, code, etc.
+
+# Ensure you're in the correct directory when running commands
+pwd  # Should be in the project directory containing .env
+```
+
+---
+
+### Issue: "Invalid Nextcloud credentials"
+
+**Cause:** BasicAuth credentials are incorrect or the app password has been revoked.
+
+**Solution:**
+
+1. **Verify username:**
+   ```bash
+   # Username should match your Nextcloud login
+   echo $NEXTCLOUD_USERNAME
+   ```
+
+2. **Generate a new app password:**
+   - Log in to Nextcloud
+   - Go to **Settings** → **Security**
+   - Under "Devices & sessions", create a new app password
+   - Update `.env` with the new password
+
+3. **Test credentials manually:**
+   ```bash
+   curl -u "$NEXTCLOUD_USERNAME:$NEXTCLOUD_PASSWORD" \
+     "$NEXTCLOUD_HOST/ocs/v2.php/cloud/capabilities" \
+     -H "OCS-APIRequest: true"
+   # Should return XML with capabilities
+   ```
+
+---
+
+## Server Issues
+
+### Issue: "Address already in use" / Port conflict
+
+**Cause:** Another process is using port 8000.
+
+**Solution:**
+
+**Option 1: Use a different port**
+```bash
+uv run nextcloud-mcp-server --port 8080
+```
+
+**Option 2: Find and kill the process using the port**
+```bash
+# On Linux/macOS
+lsof -ti:8000 | xargs kill -9
+
+# On Windows
+netstat -ano | findstr :8000
+taskkill /PID <pid> /F
+```
+
+**Option 3: Stop other MCP server instances**
+```bash
+# Check for running instances
+ps aux | grep nextcloud-mcp-server
+
+# Kill specific process
+kill <pid>
+```
+
+---
+
+### Issue: Server starts but can't connect
+
+**Cause:** Server is bound to localhost only, or firewall is blocking connections.
+
+**Solution:**
+
+1. **Check server binding:**
+   ```bash
+   # Bind to all interfaces to allow network access
+   uv run nextcloud-mcp-server --host 0.0.0.0 --port 8000
+   ```
+
+2. **Test connectivity:**
+   ```bash
+   # Test from same machine
+   curl http://localhost:8000/health
+
+   # Test from network (if using --host 0.0.0.0)
+   curl http://<server-ip>:8000/health
+   ```
+
+3. **Check firewall:**
+   ```bash
+   # Linux (ufw)
+   sudo ufw allow 8000/tcp
+
+   # Linux (firewalld)
+   sudo firewall-cmd --add-port=8000/tcp --permanent
+   sudo firewall-cmd --reload
+   ```
+
+---
+
+### Issue: Server crashes or restarts frequently
+
+**Cause:** Various issues including memory limits, uncaught exceptions, or OAuth token expiration.
+
+**Solution:**
+
+1. **Check logs with debug level:**
+   ```bash
+   uv run nextcloud-mcp-server --log-level debug
+   ```
+
+2. **Monitor resource usage:**
+   ```bash
+   # Check memory and CPU
+   top -p $(pgrep -f nextcloud-mcp-server)
+   ```
+
+3. **Use process manager for automatic restart:**
+   ```bash
+   # With systemd (see Running guide for full config)
+   sudo systemctl restart nextcloud-mcp
+
+   # With Docker Compose (includes restart: unless-stopped)
+   docker-compose up -d
+   ```
+
+4. **Check for OAuth credential expiration** (if using dynamic registration):
+   - See ["Stored client has expired"](#issue-stored-client-has-expired) above
+
+---
+
+## Connection Issues
+
+### Issue: MCP client can't authenticate
+
+**Cause:** OAuth flow failing or credentials invalid.
+
+**Solution:**
+
+**For OAuth:**
+1. Verify OAuth is configured correctly:
+   ```bash
+   uv run nextcloud-mcp-server --oauth --log-level debug
+   # Look for "OAuth initialization complete"
+   ```
+
+2. Check that OIDC app is accessible:
+   ```bash
+   curl https://your.nextcloud.instance.com/.well-known/openid-configuration
+   ```
+
+3. Verify MCP_SERVER_URL matches your setup:
+   ```bash
+   echo $NEXTCLOUD_MCP_SERVER_URL
+   # Should match the URL clients use to connect
+   ```
+
+**For BasicAuth:**
+1. Verify credentials work:
+   ```bash
+   curl -u "$NEXTCLOUD_USERNAME:$NEXTCLOUD_PASSWORD" \
+     "$NEXTCLOUD_HOST/ocs/v2.php/cloud/capabilities" \
+     -H "OCS-APIRequest: true"
+   ```
+
+---
+
+### Issue: Tools return errors or don't work
+
+**Cause:** Missing Nextcloud apps, incorrect permissions, or API issues.
+
+**Solution:**
+
+1. **Verify required Nextcloud apps are installed:**
+   - Notes: Install "Notes" app
+   - Calendar: Ensure CalDAV is enabled
+   - Contacts: Ensure CardDAV is enabled
+   - Deck: Install "Deck" app
+
+2. **Check user permissions:**
+   - Ensure the authenticated user has access to the resources
+   - Check sharing permissions for shared resources
+
+3. **Test API directly:**
+   ```bash
+   # Test Notes API
+   curl -u "$NEXTCLOUD_USERNAME:$NEXTCLOUD_PASSWORD" \
+     "$NEXTCLOUD_HOST/apps/notes/api/v1/notes"
+
+   # Test with OAuth Bearer token
+   curl -H "Authorization: Bearer $TOKEN" \
+     "$NEXTCLOUD_HOST/apps/notes/api/v1/notes"
+   ```
+
+4. **Check server logs for specific errors:**
+   ```bash
+   uv run nextcloud-mcp-server --log-level debug
+   ```
+
+---
+
+## Getting Help
+
+If you continue to experience issues:
+
+### 1. Enable Debug Logging
+
+```bash
+uv run nextcloud-mcp-server --log-level debug
+```
+
+Review the logs for specific error messages.
+
+### 2. Verify OIDC Configuration (OAuth mode)
+
+```bash
+# Check OIDC discovery
+curl https://your.nextcloud.instance.com/.well-known/openid-configuration
+
+# Check registration endpoint exists
+curl https://your.nextcloud.instance.com/.well-known/openid-configuration | jq '.registration_endpoint'
+```
+
+### 3. Test Nextcloud API Access
+
+```bash
+# Test OCS API (should work with OAuth)
+curl -H "Authorization: Bearer $TOKEN" \
+  "$NEXTCLOUD_HOST/ocs/v2.php/cloud/capabilities?format=json" \
+  -H "OCS-APIRequest: true"
+
+# Test app API (may need patch - see oauth2-bearer-token-session-issue.md)
+curl -H "Authorization: Bearer $TOKEN" \
+  "$NEXTCLOUD_HOST/apps/notes/api/v1/notes"
+```
+
+### 4. Check Versions
+
+```bash
+# MCP Server version
+uv run nextcloud-mcp-server --version
+
+# Python version
+python3 --version
+
+# Nextcloud version (check in admin panel)
+```
+
+### 5. Open an Issue
+
+If problems persist, open an issue on the [GitHub repository](https://github.com/cbcoutinho/nextcloud-mcp-server/issues) with:
+
+- **Server logs** (with `--log-level debug`)
+- **Nextcloud version**
+- **OIDC app version** (if using OAuth)
+- **Error messages**
+- **Steps to reproduce**
+- **Environment details** (OS, Python version, Docker vs local)
+
+---
+
+## See Also
+
+- [OAuth Setup Guide](oauth-setup.md) - OAuth configuration
+- [Configuration](configuration.md) - Environment variables
+- [Running the Server](running.md) - Server options
+- [OAuth Bearer Token Issue](oauth2-bearer-token-session-issue.md) - Required patch