04 | cwprep and cwtwb Basic Cases: Script + MCP

What You Will Learn

• The minimum script pattern for direct usage
• The minimum MCP prompt pattern in AI clients
• Clear division of responsibilities between cwprep and cwtwb

Prerequisites

• MCP setup and connectivity check completed
• A demo-ready data source (table or CSV)

Case A: cwprep (Data Flow)

cwprep generates Tableau Prep flows (.tfl/.tflx).

Script Pattern

flow = {
  "flow_name": "orders_filter_demo",
  "connection": {"type": "database", "host": "localhost", "db_class": "mysql", "username": "root", "dbname": "demo"},
  "nodes": [
    {"type": "input_table", "name": "orders", "table": "orders"},
    {"type": "filter", "name": "sales_filter", "parent": "orders", "expression": "[sales] > 100"},
  ]
}

MCP Prompt Pattern

Use cwprep:
1) input table orders
2) filter sales > 100
3) output tfl to local output/demo.tfl

Case B: cwtwb (Workbook)

cwtwb generates Tableau workbooks (.twb/.twbx).

Script Pattern

Core actions are usually:

• Create workbook
• Connect data source
• Create worksheet
• Configure chart
• Save as .twb/.twbx

MCP Prompt Pattern

Use cwtwb:
1) load superstore data
2) create a Sales by Category bar chart worksheet
3) save to output/sales_by_category.twb

How They Work Together

• Use cwprep first to clean and shape data
• Use cwtwb second to build dashboards on top of that data

Validation Checklist

• One .tfl/.tflx generated successfully
• One .twb/.twbx generated successfully
• You can explain why cwprep -> cwtwb is the default order

First-Practice Tips

• Start from minimal cases, not full dashboards
• Keep prompts and outputs for reproducibility
• If it fails, isolate first: script command first, MCP config second