claude-hidden-toolkit/tool-catalog/hidden-tools/office-addin-tools.md

Office Add-in Tools (5 tools)

Status: UNTESTED — requires Microsoft Office (Excel/Word/PowerPoint) with the Claude add-in connected. tool_search returns nothing for "office", "workbook", or "addin" in any session type, indicating these tools are only registered when the Office add-in WebSocket bridge is active.

Verified: 2026-03-19. Could not test (no Office installed). Schemas documented from binary extraction only.

Tools for direct Excel/Word/PowerPoint integration via the Claude add-in panel. Requires the Office add-in to be installed and connected to Claude Desktop.

Manifest URL: https://pivot.claude.ai/manifest.xml Add-in UUID: 29673e3c-d826-4f00-92ee-162334a52b1a Module ID: office-addin OAuth scope (when enabled): user:inference user:office

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open_office_file

Opens an Office file in the default application and automatically opens the Claude add-in panel.

On macOS, the add-in is opened using the Accessibility API (requires Accessibility permissions). On Windows, the add-in auto-opens via manifest configuration.

After opening, use office_addin_run or office_addin_get_context to interact with the file.

Parameters

Param	Type	Required	Description
path	string	yes	Absolute path to the Office file to open

Supported file types

• .xlsx → Microsoft Excel
• .docx → Microsoft Word
• .pptx → Microsoft PowerPoint

Notes

• macOS requires Accessibility permissions for the add-in panel auto-open
• The app-to-application mapping is hardcoded
• Throws Unknown Office extension for any other file type
• The tool description mentions office_addin_task as an alternative to office_addin_run — this name appears in the description text but has no separate tool registration

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close_office_file

Closes an Office file that is currently open.

Parameters

Param	Type	Required	Default	Description
path	string	yes	—	Absolute path to the Office file to close
save_changes	boolean	no	true	If true, saves changes before closing. If false, discards changes.

Notes

• Only works with .xlsx, .docx, .pptx
• The file must actually be open in the corresponding Office application
• Default is to save

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office_addin_run

Execute Office.js code directly in Excel. Changes appear instantly in the document.

The code runs inside Excel.run() with context available.

Parameters

Param	Type	Required	Description
code	string	yes	Office.js code to execute. Has context object available. Must call await context.sync() to apply changes.
display_message	string	no	Brief user-friendly action label shown in the add-in UI (e.g., "Calculate sum", "Create chart")
workbook	string	no	Target workbook ID (addinId). If not specified, uses the currently selected workbook. Use list_connected_workbooks to see available workbooks.

Code examples from description

Write to cell:

context.workbook.worksheets.getActiveWorksheet().getRange("A1").values = [["Hello"]];
await context.sync();

Read data:

const range = context.workbook.worksheets.getActiveWorksheet().getRange("A1:B10");
range.load("values");
await context.sync();
range.values; // Returns the data

Notes

• Must call await context.sync() after making changes
• User must have the Excel add-in open and connected to Claude Desktop
• Currently only described for Excel, even though open_office_file supports Word and PowerPoint
• The display_message shows in the add-in UI as a status indicator

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office_addin_get_context

Fetch current spreadsheet context: selection, sheets, recent changes, and add-in conversation history.

Parameters

Param	Type	Required	Default	Description
include_changes	boolean	no	true	Include user change events (edits, inserts, deletes, etc.)
include_conversation	boolean	no	true	Include the add-in conversation history
include_selection	boolean	no	true	Include current cursor/selection and its values
include_sheets	boolean	no	true	Include sheet metadata (names, dimensions, frozen rows/cols)
max_changes	number	no	100	Maximum number of change events to return
max_messages	number	no	50	Maximum number of conversation messages to return
workbook	string	no	—	Target workbook ID (addinId). If not specified, uses currently selected workbook.

Returns

• Current selection address and values
• All sheet names and metadata
• Recent user edits, inserts, deletes
• Prior conversation with the add-in Claude

Notes

• The "add-in conversation" is a separate conversation the user may have had with the Claude embedded in Excel — this provides context on what was discussed
• All includes default to true — pass false to reduce response size

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list_connected_workbooks

List all Excel workbooks currently connected via the Claude add-in.

Parameters

None.

Returns

Connected workbooks with their IDs, document names, and connection details. Use the returned workbook IDs to target specific workbooks in office_addin_run and office_addin_get_context.

Notes

• Returns addinId values used as the workbook parameter in other tools
• Multiple workbooks can be connected simultaneously
• Connection is via WebSocket (wss://localhost:8766 or configured OFFICE_ADDIN_BRIDGE_URL)
• If no workbooks are connected, the other tools default to "currently selected" which may fail

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Architecture

The Office add-in system uses:

1. WebSocket bridge — connects Claude Desktop to the Excel add-in running inside Office
2. OAuth authentication — uses the user's Claude token with user:office scope
3. Office.js API — code runs in Excel's JavaScript runtime via Excel.run()
4. Accessibility API (macOS) — used to auto-open the add-in panel when opening files
5. Profile API — fetches user's account UUID from {apiHost}/api/oauth/profile