Skip to main content

Documentation Index

Fetch the complete documentation index at: https://duomi.mintlify.app/llms.txt

Use this file to discover all available pages before exploring further.

​
Chart Blocks

Use a chart block when the template slide contains a bar or column chart region and your request needs to provide chart data. The template supplies placement and default styling. The payload supplies categories, series, chart type, and optional formatting overrides.

​
Basic Shape

Inside slide_data.content.blocks, a chart block looks like this: 
{
  "type": "chart",
  "chart": {
    "chart_type": "stacked_column",
    "categories": ["Q2", "Q3", "Q4"],
    "series": [
      { "name": "Committed", "values": [18.2, 21.4, 24.1] },
      { "name": "Upside", "values": [4.5, 3.9, 5.2] }
    ]
  }
}
Each series must have one value per category.

​
Supported Chart Types

Chart blocks support bar and column charts only.
TypeUse when
clustered_columnCompare series side by side with vertical columns
stacked_columnShow stacked contribution by category with vertical columns
percent_stacked_columnShow each category as 100% with vertical columns
clustered_barCompare series side by side with horizontal bars
stacked_barShow stacked contribution by category with horizontal bars
percent_stacked_barShow each category as 100% with horizontal bars
If you omit chart_type, generation preserves the template chart type where supported. Pie, line, area, scatter, combo, and other arbitrary PowerPoint chart types are not part of the supported chart block API.

​
Categories and Series

categories defines the labels along the category axis. For column charts, categories appear on the X-axis. For bar charts, categories appear on the Y-axis. series defines the plotted values. Each series has a name, a values array, and an optional color. 
{
  "categories": ["Q2", "Q3", "Q4"],
  "series": [
    { "name": "Committed", "values": [18.2, 21.4, 24.1], "color": "#0F766E" },
    { "name": "Upside", "values": [4.5, 3.9, 5.2], "color": "#2563EB" },
    { "name": "At risk", "values": [2.1, 3.4, 2.8], "color": "#DC2626" }
  ]
}
If a series color is omitted, the renderer uses the template or default chart colors.

​
Titles, Legends, and Axes

Chart blocks can specify the chart title, legend, value axis, and category axis. 
{
  "title": "Renewal Outlook by Cohort",
  "title_format": {
    "font_size": 14,
    "bold": true,
    "color": "#111827"
  },
  "legend": {
    "show": true,
    "position": "bottom",
    "text_format": { "font_size": 8 }
  },
  "value_axis": {
    "title": "ARR",
    "number_format": "#,##0",
    "label_format": { "font_size": 8 }
  },
  "value_axis_unit": "$M",
  "category_axis": {
    "label_rotation": -45,
    "label_format": { "font_size": 8 }
  }
}
Legend positions are bottom, left, right, top, and top_right. Axis fields include visible, title, title_format, label_format, label_rotation, number_format, min_value, and max_value.

​
Bar Labels

Set show_bar_labels: true to add total labels to stacked bars or columns. 
{
  "chart_type": "stacked_column",
  "show_bar_labels": true
}
This is most useful for stacked_column, stacked_bar, percent_stacked_column, and percent_stacked_bar. Bar labels are calculated automatically from the chart series values.

​
Data Rows

Use data_rows to add a small data table beneath the chart. These values are part of the input payload; the API positions and formats the rows, but it does not derive values like n= or NPS from the chart series. 
{
  "data_rows": [
    ["Total ARR", "$24.8M", "$28.7M", "$32.1M"],
    ["At-risk %", "8%", "12%", "9%"]
  ],
  "data_table_header_column": true,
  "data_table_format": {
    "font_name": "Arial",
    "font_size": 8,
    "color": "#333333"
  }
}
Providing data_rows automatically enables the chart data table. If data_table_header_column is true, the first value in each row is treated as a row label.

​
Complete Example

{
  "title": "Customer NPS Scores by Company",
  "footnote": "Source: Q4 2024 Customer Satisfaction Survey",
  "content": {
    "blocks": [
      {
        "type": "chart",
        "chart": {
          "chart_type": "percent_stacked_column",
          "categories": [
            "Acme Corp",
            "TechFlow Inc",
            "DataSync Ltd",
            "CloudFirst",
            "Innovate Labs",
            "SecureNet",
            "GrowthMetrics",
            "Nexus Digital"
          ],
          "series": [
            {
              "name": "Promoters (9-10)",
              "values": [
                45,
                38,
                12,
                28,
                52,
                31,
                8,
                42
              ]
            },
            {
              "name": "Passives (7-8)",
              "values": [
                32,
                35,
                25,
                38,
                28,
                42,
                22,
                33
              ]
            },
            {
              "name": "Detractors (0-6)",
              "values": [
                23,
                27,
                63,
                34,
                20,
                27,
                70,
                25
              ]
            }
          ],
          "legend": {
            "position": "top"
          },
          "show_bar_labels": true,
          "data_rows": [
            [
              "n=",
              "156",
              "142",
              "89",
              "178",
              "201",
              "134",
              "67",
              "188"
            ],
            [
              "NPS",
              "+22",
              "+11",
              "-51",
              "-6",
              "+32",
              "+4",
              "-62",
              "+17"
            ]
          ],
          "data_table_header_column": true,
          "data_table_format": {
            "font_name": "Arial",
            "color": "#000000",
            "bold": false,
            "italic": false,
            "underline": false
          }
        }
      },
      {
        "type": "text",
        "text": {
          "text": "Question: What is driving the significant detractor rates at DataSync Ltd and GrowthMetrics?"
        }
      }
    ]
  }
}
The visual example below is generated from the complete payload above. It shows the API-added total labels above each stacked column and the aligned data rows beneath the chart.
Template slide with a placeholder chart before chart data is generated.
Generated stacked column chart with total labels above each column and data rows aligned beneath the chart.

​
Updating Charts Later

Use chart blocks when you are generating a supported bar or column chart slide from a template. Use Chart Updates when a .pptx already exists and you only need to refresh the chart data. Chart updates are useful when:
  • New data arrives after the deck was generated
  • A user manually edited the deck in PowerPoint and you want to preserve those edits
  • You want to keep chart formatting, colors, legends, axes, bar labels, and data-row positioning while replacing the underlying numbers
For updates, send data fields such as categories, series, data_rows, and data_table_header_column. Omit styling fields such as chart_type, title, legend, and axes when you want the existing chart formatting preserved.

Presentation Generation

Generate one slide or a full deck.

Table Blocks

Author table rows and formatting.

Text Blocks

Author slide text and text sections.