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+# Deployment Troubleshooting Guide
+
+## Known Issues & Solutions
+
+### 1. Database Password with Special Characters in DATABASE_URL
+
+**Problem**: When the database password contains special characters (especially `%`), the backend container fails to connect with:
+```
+sqlalchemy.exc.OperationalError: (psycopg.OperationalError) connection failed:
+  FATAL: password authentication failed for user "postgres"
+```
+
+**Root Cause**: The `DATABASE_URL` uses URL encoding. When the password contains `%`, the URL parser interprets it as a URL-encoded character. For example, `%81` gets decoded as a single byte instead of the literal characters `%81`.
+
+**Example**:
+- Original password: `zmfCSR%816709301`
+- In docker-compose.yml `POSTGRES_PASSWORD`: use **exact** password: `zmfCSR%816709301`
+- In `DATABASE_URL`: must URL-encode the `%` as `%25`: `zmfCSR%25816709301`
+
+**Solution**:
+```yaml
+# docker-compose.server.yml
+environment:
+  POSTGRES_PASSWORD: zmfCSR%816709301  # Exact password for postgres
+  DATABASE_URL: postgresql+psycopg://postgres:zmfCSR%25816709301@postgres:5432/ai_contract_platform
+```
+
+**Rule of thumb**: Any `%` in a URL must be written as `%25`. This applies to `DATABASE_URL`, `REDIS_URL`, and any other URL-based configuration.
+
+**Quick fix command** (on server):
+```bash
+cd /opt/ai-contract-platform
+# Stop backend
+docker compose -f docker-compose.server.yml stop backend
+# Fix DATABASE_URL: replace % with %25 in docker-compose.server.yml
+sed -i 's|zmfCSR%816709301|zmfCSR%25816709301|g' docker-compose.server.yml
+# Verify
+grep DATABASE_URL docker-compose.server.yml
+# Restart
+docker compose -f docker-compose.server.yml up -d backend
+```
+
+### 2. Missing Template Files at Startup
+
+**Problem**: Backend crashes on startup with:
+```
+FileNotFoundError: [Errno 2] No such file or directory:
+  '/project-docs/phase13-legal-knowledge-template-library/contract-templates/...'
+```
+
+**Root Cause**: Docker build doesn't include `project-docs/` directory. The `template_service.py` tries to load template markdown files at import time.
+
+**Solution**: Fixed in commit `323e7cf`. The `_load_phase13_template_asset` function now:
+1. Returns `None` if source files are missing
+2. Filters out `None` entries from `DEFAULT_TEMPLATES` at module load time
+
+### 3. Missing `_context` Method in RemoteSharedAIPlatformClient
+
+**Problem**: Chat API returns 500 error:
+```
+AttributeError: 'RemoteSharedAIPlatformClient' object has no attribute '_context'
+```
+
+**Root Cause**: The `RemoteSharedAIPlatformClient` class uses `self._context(current_user)` in many methods, but the method was never defined.
+
+**Solution**: Fixed in commit `3ff384c`. Added the `_context` method:
+```python
+def _context(self, current_user: Dict[str, Any]) -> SharedAIRequestContext:
+    return SharedAIRequestContext(
+        tenant_id=current_user.get("tenant_id", ""),
+        user_id=current_user.get("id", ""),
+        user_role=current_user.get("role", "admin"),
+    )
+```
+
+## Deployment Checklist
+
+1. **Verify password encoding**: Check `DATABASE_URL` in `docker-compose.server.yml` has `%` encoded as `%25`
+2. **Pull latest code**: `git pull origin main`
+3. **Clean rebuild**: `docker compose -f docker-compose.server.yml down && docker compose -f docker-compose.server.yml up -d --build`
+4. **Wait for postgres**: The `backend` container depends on `postgres` health check (up to 20 retries)
+5. **Verify**: `curl -s http://localhost:8001/health` should return `{"status":"ok"}`
+
+## Server Information
+
+- **Server**: 192.168.3.90
+- **Project directory**: `/opt/ai-contract-platform`
+- **SSH key**: `~/.ssh/water_audit_ed25519`
+- **SSH user**: `root`
+- **Gitea**: http://192.168.3.90:3000
+- **Frontend**: http://192.168.3.90:3003
+- **Backend API**: http://192.168.3.90:8001
+- **Database password**: `zmfCSR%816709301` (use `%25` in URLs)