cwtwb 0.18.3

Tableau Workbook (.twb) generation toolkit and MCP server

cwtwb

Tableau Workbook (.twb/.twbx) generation toolkit for reproducible dashboards and workbook engineering Programmatically create Tableau workbooks with stable analytical primitives, dashboard composition, and built-in structural validation.

Author: Cooper Wenhua <[e-mail]>

Overview

cwtwb is a Model Context Protocol (MCP) server and Python toolkit for generating Tableau Desktop workbook files (.twb / .twbx) from code or AI-driven tool calls.

It is designed as a workbook engineering layer, not as a conversational data exploration agent. The goal is to make workbook generation reproducible, inspectable, and safe to automate in local workflows, scripts, and CI.

The default workflow is:

1. Start from a known template (.twb or .twbx) or the built-in zero-config template
2. Add calculated fields and parameters
3. Build worksheets from stable chart primitives
4. Assemble dashboards and interactions
5. Save and validate a .twb or .twbx that opens in Tableau Desktop

The default MCP entrypoint exposes the low-level workbook engineering tools only. Experimental guided authoring code is still present in the package, but it is not registered in the default MCP tool or prompt surface so agents do not accidentally enter a long guided workflow when a direct workbook edit is wanted.

                            Interfaces
  ┌───────────────────────────────────────────────────────────────┐
  │  ┌──────────────────────────┐  ┌───────────────────────────┐  │
  │  │        MCP Server        │  │      Python Library       │  │
  │  │  tools_workbook          │  │  from cwtwb.twb_editor    │  │
  │  │  tools_layout            │  │  import TWBEditor         │  │
  │  │  tools_migration         │  │                           │  │
  │  │  tools_support           │  │  editor.add_...()         │  │
  │  │                          │  │  editor.configure_...()   │  │
  │  │  (Claude / Cursor /      │  │  editor.save(...)         │  │
  │  │   VSCode / Claude Code)  │  │                           │  │
  │  └─────────────┬────────────┘  └──────────────┬────────────┘  │
  │                └──────────────┬────────────────┘               │
  └─────────────────────────────  ┼  ─────────────────────────────┘
                                  ▼
  ┌───────────────────────────────────────────────────────────────┐
  │                          TWBEditor                            │
  │       ParametersMixin  ·  ConnectionsMixin                    │
  │       ChartsMixin      ·  DashboardsMixin                     │
  └──────────┬──────────────────┬──────────────────┬─────────────┘
             ▼                  ▼                  ▼
  ┌──────────────────┐  ┌──────────────┐  ┌──────────────────────┐
  │  Chart Builders  │  │  Dashboard   │  │  Analysis &          │
  │                  │  │  System      │  │  Migration           │
  │  Basic  DualAxis │  │              │  │                      │
  │  Pie    Text     │  │  layouts     │  │  migration.py        │
  │  Map    Recipes  │  │  actions     │  │  twb_analyzer.py     │
  │                  │  │  dependencies│  │  capability_registry │
  └────────┬─────────┘  └──────┬───────┘  └──────────┬───────────┘
           └───────────────────┼──────────────────────┘
                               ▼
  ┌───────────────────────────────────────────────────────────────┐
  │                     XML Engine  (lxml)                        │
  │    template.twb/.twbx  →  patch  →  validate  →  save        │
  └───────────────────────────────┬───────────────────────────────┘
                                  ▼
                      output.twb  /  output.twbx

Installation

pip install cwtwb

To run the bundled Hyper-backed example that inspects .hyper files and resolves the physical Orders_* table automatically, install the optional example dependency as well:

pip install "cwtwb[examples]"

Requirements

• Python >= 3.10
• lxml >= 5.0
• uv
• mcp >= 1.0

Quick Start

As MCP Server

To allow an MCP client to build Tableau workbooks automatically, add cwtwb to that client's MCP configuration.

The launch command is the same across clients:

uvx cwtwb

Each client stores this command in a different configuration format. Use the matching example below.

Claude Desktop

Open ~/Library/Application Support/Claude/claude_desktop_config.json on macOS or %APPDATA%\Claude\claude_desktop_config.json on Windows and add:

{
  "mcpServers": {
    "cwtwb": {
      "command": "uvx",
      "args": ["cwtwb"]
    }
  }
}

Cursor IDE

1. Open Cursor Settings -> Features -> MCP
2. Click Add New MCP Server
3. Set Type to command
4. Set Name to cwtwb
5. Set Command to uvx cwtwb

Claude Code

claude mcp add cwtwb -- uvx cwtwb

VSCode

Open the workspace .vscode/mcp.json file or your user-profile mcp.json file and add:

{
  "servers": {
    "cwtwb": {
      "command": "uvx",
      "args": ["cwtwb"]
    }
  }
}

In VSCode, you can open these files from the Command Palette with MCP: Open Workspace Folder Configuration or MCP: Open User Configuration. You can also use MCP: Add Server and enter the same uvx cwtwb command through the guided flow.

For local testing without uvx, you can also start the server with:

python -m cwtwb.mcp

As Python Library

Use TWBEditor(...) to start from a template and rebuild workbook content. Use TWBEditor.open_existing(...) when you want to keep existing worksheets and dashboards and reconfigure a sheet in place.

from cwtwb.twb_editor import TWBEditor

editor = TWBEditor("")  # "" uses the built-in Superstore template
editor.clear_worksheets()
editor.add_calculated_field("Profit Ratio", "SUM([Profit])/SUM([Sales])")

editor.add_worksheet("Sales by Category")
editor.configure_chart(
    worksheet_name="Sales by Category",
    mark_type="Bar",
    rows=["Category"],
    columns=["SUM(Sales)"],
)

editor.add_worksheet("Segment Pie")
editor.configure_chart(
    worksheet_name="Segment Pie",
    mark_type="Pie",
    color="Segment",
    wedge_size="SUM(Sales)",
)

editor.add_dashboard(
    dashboard_name="Overview",
    worksheet_names=["Sales by Category", "Segment Pie"],
    layout="horizontal",
)

editor.save("output/my_workbook.twb")

Clone and Refactor an Existing Worksheet

Use worksheet clone/refactor when you want to duplicate an existing visual module and rebind only the cloned worksheet to a different core measure. This is especially useful for KPI cards such as turning a Sales KPI worksheet into an independent Profit KPI worksheet while preserving the original sheet.

from cwtwb.twb_editor import TWBEditor

editor = TWBEditor.open_existing("examples/worksheet_refactor_kpi_profit/5 KPI Design Ideas (2).twb")

editor.clone_worksheet("1. KPI", "1. KPI Profit")
editor.apply_worksheet_refactor("1. KPI Profit", {"Sales": "Profit"})
editor.set_worksheet_hidden("1. KPI Profit", hidden=False)

editor.save("output/kpi_profit_clone.twb")

Available worksheet-refactor helpers:

• clone_worksheet(source_worksheet, target_worksheet)
• preview_worksheet_refactor(worksheet_name, replacements)
• apply_worksheet_refactor(worksheet_name, replacements)
• set_worksheet_hidden(worksheet_name, hidden=True)

apply_worksheet_refactor(...) now also performs a worksheet-local identity normalization pass for generic Tableau Calculation_* fields. This stabilizes pill labels after clone-and-replace workflows and returns post_process evidence describing renamed calculation identities and worksheet-local rewrite maps.

Working with Packaged Workbooks (.twbx)

.twbx files are ZIP archives that bundle the workbook XML together with data extracts (.hyper) and image assets. cwtwb reads and writes them transparently:

from cwtwb.twb_editor import TWBEditor

# Open a packaged workbook — extracts and images are preserved automatically
editor = TWBEditor.open_existing("templates/dashboard/MyDashboard.twbx")

# Make changes as usual
editor.add_calculated_field("Profit Ratio", "SUM([Profit])/SUM([Sales])")

# Save as .twbx — re-bundles the updated .twb with the original extracts/images
editor.save("output/MyDashboard_v2.twbx")

# Or extract just the XML when the packaged format isn't needed
editor.save("output/MyDashboard_v2.twb")

A plain .twb can also be packaged:

editor = TWBEditor("templates/twb/superstore.twb")
# ...
editor.save("output/superstore.twbx")  # produces a single-entry ZIP with the .twb inside

MCP Tools

Tool	Description
create_workbook	Load a .twb or .twbx template and initialize a rebuild-from-template workspace
open_workbook	Open an existing .twb or .twbx and keep its worksheets and dashboards for editing
list_fields	List all available dimensions and measures
list_worksheets	List worksheet names in the active workbook
list_dashboards	List dashboards and the worksheet zones they reference
add_parameter	Add an interactive parameter for what-if analysis
add_calculated_field	Add a calculated field with Tableau formula
remove_calculated_field	Remove a previously added calculated field
clone_worksheet	Clone an existing worksheet and its worksheet window
preview_worksheet_refactor	Preview worksheet-scoped field rewrites before mutating the workbook
apply_worksheet_refactor	Apply worksheet-scoped field rewrites while preserving the original worksheet
add_worksheet	Add a new blank worksheet
configure_chart	Configure chart type and field mappings
configure_worksheet_style	Apply worksheet-level styling: background color, axis/grid/border visibility
configure_dual_axis	Configure a dual-axis chart composition
configure_chart_recipe	Configure a showcase recipe chart such as lollipop, donut, butterfly, or calendar
add_dashboard	Create a dashboard combining worksheets
add_dashboard_action	Add filter, highlight, URL, or go-to-sheet actions to a dashboard
set_worksheet_caption	Set or clear a worksheet caption using plain text
set_worksheet_hidden	Hide or unhide a worksheet by updating its worksheet window metadata
generate_layout_json	Build an interactive structured dashboard flexbox layout
list_capabilities	Show cwtwb's declared support boundary
describe_capability	Explain whether a chart or feature is core, advanced, recipe, or unsupported
analyze_twb	Analyze a .twb file against the capability catalog; output includes both the full capability breakdown and the capability gap triage summary
diff_template_gap	Summarize the non-core gap of a template
validate_workbook	Validate a workbook against the official Tableau TWB XSD schema (2026.1)
set_excel_connection	Configure the datasource to use a local Excel workbook and register fields from the selected sheet
set_mysql_connection	Configure the datasource to use a local MySQL connection
set_tableauserver_connection	Configure connection to an online Tableau Server
set_hyper_connection	Configure the datasource to use a local Hyper extract connection
save_workbook	Save the workbook as .twb (plain XML) or .twbx (ZIP with bundled extracts and images)

Important save semantics for agents:

• save_workbook(output_path=...) is the only default MCP tool that writes the active in-memory workbook to disk.
• validate_workbook() validates the active in-memory workbook or an existing file, but it does not save or export anything.
• analyze_twb(file_path=...) requires an existing .twb or .twbx path. For a newly generated workbook, call save_workbook first, then call analyze_twb on the saved path.
• Migration tools are for repointing existing workbooks to new datasources; they are not a substitute for saving the active workbook.

MCP Prompts

The default MCP entrypoint currently registers no prompts. This is intentional: the default server is optimized for direct tool calling through the workbook engineering surface.

Guided Authoring Status

The datasource-first guided authoring implementation remains in the source tree for future use, but it is hidden from the default MCP entrypoint. In practical terms:

• The Python modules such as cwtwb.authoring_run and cwtwb.mcp.tools_authoring still exist.
• The default cwtwb MCP command does not import tools_authoring.py, so guided tools such as start_authoring_run and generate_workbook_from_run are not registered.
• The default MCP command does not register guided prompts such as guided_dashboard_authoring.
• The default MCP resources do not expose the guided authoring contract template or authoring_workflow skill.

To restore guided authoring later, re-register the guided modules from an MCP entrypoint by importing cwtwb.mcp.tools_authoring and the guided prompt module. For now, keeping them hidden prevents agents from choosing a long guided workflow when the intended task is a direct workbook edit.

Capability Model

Core primitives

These are the stable building blocks the project should continue to promise:

• Bar
• Line
• Area
• Pie
• Map
• Text / KPI cards
• Parameters and calculated fields
• Basic dashboard composition

Advanced patterns

These are supported, but they are higher-level compositions or interaction features rather than the default surface area:

• Scatterplot
• Heatmap
• Tree Map
• Bubble Chart
• Dual Axis — mark_color_1/2, color_map_1, reverse_axis_1, hide_zeroline, synchronized
• Table Calculations — RANK_DENSE, RUNNING_SUM, WINDOW_SUM via add_calculated_field(table_calc="Rows")
• KPI Difference badges — MIN(1) dummy axis + axis_fixed_range + color_map + customized_label
• Donut (via extra_axes) — multi-pane Pie + white circle using configure_dual_axis(extra_axes=[...]); supports color_map for :Measure Names palette
• Rich-text labels — configure_chart(label_runs=[...]) for multi-style KPI cards and dynamic titles with inline field values
• Advanced worksheet styling — configure_worksheet_style supports pane-level cell/datalabel/mark styles, per-field label/cell/header formats, axis tick control, tooltip disabling, and all Tableau visual noise suppressions
• Row dimension header suppression — configure_worksheet_style(hide_row_label="FieldName")
• Filter zones, parameter controls, color legends
• Dashboard filter, highlight, URL, and go-to-sheet actions
• Worksheet captions
• Declarative JSON layout workflows
• Dashboard zone title control via show_title: false in layout dicts

Recipes and showcase patterns

These can be generated today, but they should be treated as recipes or examples rather than first-class promises:

• Donut
• Lollipop
• Bullet
• Bump
• Butterfly
• Calendar

Recipe charts are intentionally exposed through a single configure_chart_recipe tool so the public MCP surface does not grow one tool at a time for every showcase pattern.

This distinction matters because cwtwb is not trying to become a chart zoo or compete with Tableau's own conversational analysis tooling. The project is strongest when it provides a reliable, automatable workbook generation layer.

Capability-first workflow

When you are not sure whether something belongs in the stable SDK surface:

1. Use list_capabilities to inspect the declared boundary
2. Use describe_capability to check a specific chart, encoding, or feature
3. Use analyze_twb or diff_template_gap before chasing a showcase template

This keeps new feature work aligned with the project's real product boundary instead of with whatever happens to appear in a sample workbook.

Built-in Validation

Structural validation

save() automatically validates the TWB XML before publishing the final file:

• Fatal errors such as missing <workbook> or <datasources> raise TWBValidationError
• Warnings such as missing <view> or <panes> are logged but do not block saving
• The workbook is first written to a same-directory temporary file, then parsed back from disk
• The saved .twb or packaged .twbx is checked against the Tableau TWB XSD when the vendored schema is available
• Strict XSD errors raise TWBValidationError; known Tableau compatibility warnings remain non-fatal
• The final output path is replaced only after the temporary file passes validation
• Validation can be disabled with editor.save("output.twb", validate=False) or editor.save("output.twbx", validate=False)

XSD schema validation

TWBEditor.validate_schema() checks the workbook against the official Tableau TWB XSD schema (2026.1). Source checkouts use vendor/tableau-document-schemas/; installed packages, including uvx cwtwb, use the packaged copy under cwtwb/vendor/:

result = editor.validate_schema()
print(result.to_text())
# PASS  Workbook is valid against Tableau TWB XSD schema (2026.1)
# — or —
# FAIL  Schema validation failed (2 error(s)):
#   * Element 'workbook': Missing child element(s)...

result.valid          # bool
result.errors         # list[str] — lxml error messages
result.schema_available  # False only if neither the packaged nor source schema is available

The same check is available as an MCP tool:

validate_workbook()                       # validate current open workbook in memory
validate_workbook(file_path="out.twb")    # validate a file on disk (.twb or .twbx)

When called directly, validate_workbook still returns a PASS/WARN/FAIL text summary. During save(), strict XSD errors are fail-closed and block the final output file; known Tableau compatibility warnings are reported but do not block saving.

Dashboard Layouts

Layout	Description
vertical	Stack worksheets top to bottom
horizontal	Place worksheets side by side
grid-2x2	2x2 grid layout for up to four worksheets
dict or .json path	Declarative custom layouts for more complex dashboards

Custom layouts can be built programmatically using a nested layout dictionary or via generate_layout_json for MCP workflows.

Use the canonical layout tree shape for nested dashboards:

{
  "type": "container",
  "direction": "horizontal",
  "children": [
    {"type": "worksheet", "name": "Sidebar", "fixed_size": 160},
    {
      "type": "container",
      "direction": "vertical",
      "children": [
        {"type": "worksheet", "name": "Header", "fixed_size": 80},
        {"type": "worksheet", "name": "Main Chart", "weight": 1}
      ]
    }
  ]
}

For compatibility with older MCP prompts and generated JSON files, add_dashboard also accepts legacy container aliases and normalizes them recursively: {"type": "horizontal", "children": [...]} and {"type": "vertical", "children": [...]}. Unknown layout node types now raise a clear error instead of silently creating an empty dashboard zone.

Hyper-backed Example

The examples/hyper_and_new_charts.py example uses the Sample - EU Superstore.hyper extract bundled directly in the package (src/cwtwb/references/) and resolves the physical Orders_* table via Tableau Hyper API before switching the workbook connection. No repository clone is needed — install with pip install "cwtwb[examples]" and run directly.

Workbook Migration

cwtwb includes a migration subsystem for switching an existing .twb to a new datasource — for example, repointing a workbook built on one Excel file to a different Excel with a different schema, or migrating between language variants of the same dataset.

How it works

Migration is a multi-step workflow. Each explicit step is available as both an MCP tool and a Python function:

1. inspect_target_schema   →  Scan the target Excel and list its columns
2. profile_twb_for_migration  →  Inventory which fields the workbook uses
3. propose_field_mapping   →  Match source fields to target columns (fuzzy)
4. preview_twb_migration   →  Dry-run: show what would change, blockers/warnings
5. apply_twb_migration     →  Write the migrated .twb + JSON reports

migrate_twb_guided remains available as a Python convenience wrapper that runs steps 2-5 in sequence and pauses automatically when only low-confidence field matches remain, returning a warning_review_bundle for human review before proceeding. It is not registered as a default MCP tool, keeping the MCP surface explicit and predictable.

Python example

from cwtwb.migration import migrate_twb_guided_json
import json

# One-call guided migration
result = migrate_twb_guided_json(
    file_path="templates/SalesDashboard.twb",
    target_source="data/new_data_source.xlsx",
    output_path="output/SalesDashboard_migrated.twb",
)
bundle = json.loads(result)

if bundle["status"] == "warning_review_required":
    # Inspect low-confidence matches and confirm or override them
    print(bundle["warning_review_bundle"])
    # Re-run with confirmed mappings
    result = migrate_twb_guided_json(
        file_path="templates/SalesDashboard.twb",
        target_source="data/new_data_source.xlsx",
        output_path="output/SalesDashboard_migrated.twb",
        mapping_overrides={"Old Field Name": "New Column Name"},
    )

MCP tool example

When using cwtwb as an MCP server, an AI agent can run the explicit workflow:

inspect_target_schema(target_source="data/new_data_source.xlsx")
→ returns column list and data types

profile_twb_for_migration(
    file_path="templates/SalesDashboard.twb",
    target_source="data/new_data_source.xlsx"
)
→ inventories source fields and workbook scope

propose_field_mapping(
    file_path="templates/SalesDashboard.twb",
    target_source="data/new_data_source.xlsx"
)
→ proposes source-to-target field mappings

preview_twb_migration(
    file_path="templates/SalesDashboard.twb",
    target_source="data/new_data_source.xlsx"
)
→ returns blockers, warnings, and planned rewrites

apply_twb_migration(
    file_path="templates/SalesDashboard.twb",
    target_source="data/new_data_source.xlsx",
    output_path="output/SalesDashboard_migrated.twb"
)
→ writes the migrated workbook and reports

Output files

A completed migration writes three files:

File	Contents
<output>.twb	Migrated workbook with rewritten field references
migration_report.json	Per-field status: mapped / warning / blocked
field_mapping.json	Final source→target field mapping for audit

Scope parameter

scope="workbook" migrates all worksheets. Pass a worksheet name to limit migration to a single sheet.

Self-contained example

examples/migrate_workflow/ contains a template .twb, the original Superstore Excel, a target Chinese-locale Superstore Excel, and a runnable script:

python examples/migrate_workflow/test_migration_workflow.py

Project Structure

cwtwb/
|-- src/cwtwb/
|   |-- __init__.py
|   |-- capability_registry.py
|   |-- config.py
|   |-- contracts/
|   |-- authoring_contract.py
|   |-- authoring_run.py
|   |-- charts/
|   |-- connections.py
|   |-- dashboard_actions.py
|   |-- dashboard_dependencies.py
|   |-- dashboard_layouts.py
|   |-- dashboards.py
|   |-- field_registry.py
|   |-- layout.py
|   |-- layout_model.py
|   |-- layout_rendering.py
|   |-- mcp/
|   |-- parameters.py
|   |-- skills/
|   |-- twb_analyzer.py
|   |-- twb_editor.py
|   |-- validator.py
|   `-- server.py
|-- tests/
|-- examples/
|-- docs/
|-- pyproject.toml
`-- README.md

Development

# Install in editable mode
pip install -e .

# Run test suite
pytest --basetemp=output/pytest_tmp

# Run the mixed showcase example
python examples/scripts/demo_all_supported_charts.py

# Run the advanced Hyper-backed example
python examples/scripts/demo_hyper_and_new_charts.py

# Run the guided migration example
python examples/migrate_workflow/test_migration_workflow.py

# Start MCP server
cwtwb

License

AGPL-3.0-or-later