AI Document Summarization Pipeline

## AI Document Pipeline Setup

1. **Mock Data**: The 'Mock Document Data' node simulates incoming JSON with an `id` and `text` field.
2. **OpenAI**: You need an OpenAI API Key. The workflow splits the text processing into two parallel branches: Summary and Key Points.
3. **Google Sheets**: Create a sheet with columns `ID`, `Summary`, and `KeyPoints` and connect your account.
4. **Error Handling**: If a document is empty, it stops. Global errors are sent to Slack.