Add tool to get merged cells (#59)

TOOLS.md

@@ -145,6 +145,19 @@ unmerge_cells(filepath: str, sheet_name: str, start_cell: str, end_cell: str) ->
 - `end_cell`: Ending cell of range
 - Returns: Success message
 
+### get_merged_cells
+
+Get merged cells in a worksheet.
+
+```python
+get_merged_cells(filepath: str, sheet_name: str) -> str
+```
+
+- `filepath`: Path to Excel file
+- `sheet_name`: Target worksheet name
+- Returns: String representation of merged cells
+
+
 ## Formula Operations
 
 ### apply_formula

src/excel_mcp/server.py

@@ -32,6 +32,7 @@ from excel_mcp.sheet import (
     rename_sheet,
     merge_range,
     unmerge_range,
+    get_merged_ranges,
 )
 
 # Get project root directory path for log file path.
@@ -469,6 +470,18 @@ def unmerge_cells(filepath: str, sheet_name: str, start_cell: str, end_cell: str
         logger.error(f"Error unmerging cells: {e}")
         raise
 
+@mcp.tool()
+def get_merged_cells(filepath: str, sheet_name: str) -> str:
+    """Get merged cells in a worksheet."""
+    try:
+        full_path = get_excel_path(filepath)
+        return str(get_merged_ranges(full_path, sheet_name))
+    except (ValidationError, SheetError) as e:
+        return f"Error: {str(e)}"
+    except Exception as e:
+        logger.error(f"Error getting merged cells: {e}")
+        raise
+
 @mcp.tool()
 def copy_range(
     filepath: str,

src/excel_mcp/sheet.py

@@ -243,6 +243,21 @@ def unmerge_range(filepath: str, sheet_name: str, start_cell: str, end_cell: str
         logger.error(f"Failed to unmerge range: {e}")
         raise SheetError(str(e))
 
+def get_merged_ranges(filepath: str, sheet_name: str) -> list[str]:
+    """Get merged cells in a worksheet."""
+    try:
+        wb = load_workbook(filepath)
+        if sheet_name not in wb.sheetnames:
+            raise SheetError(f"Sheet '{sheet_name}' not found")
+        worksheet = wb[sheet_name]
+        return [str(merged_range) for merged_range in worksheet.merged_cells.ranges]
+    except SheetError as e:
+        logger.error(str(e))
+        raise
+    except Exception as e:
+        logger.error(f"Failed to get merged cells: {e}")
+        raise SheetError(str(e))
+
 def copy_range_operation(
     filepath: str,
     sheet_name: str,