Merge 319ca8806e into b9ec13edcf

app/MindWork AI Studio/Assistants/AssistantBase.razor.cs

@@ -339,6 +339,7 @@ public abstract partial class AssistantBase<TSettings> : AssistantLowerBase wher
         this.ChatThread = new()
         {
             IncludeDateTime = false,
+            AllowChartOutput = true,
             SelectedProvider = this.ProviderSettings.Id,
             SelectedProfile = this.AllowProfiles ? this.CurrentProfile.Id : Profile.NO_PROFILE.Id,
             SystemPrompt = this.SystemPrompt,
@@ -355,6 +356,7 @@ public abstract partial class AssistantBase<TSettings> : AssistantLowerBase wher
         this.ChatThread = new()
         {
             IncludeDateTime = false,
+            AllowChartOutput = true,
             SelectedProvider = this.ProviderSettings.Id,
             SelectedProfile = this.AllowProfiles ? this.CurrentProfile.Id : Profile.NO_PROFILE.Id,
             SystemPrompt = this.SystemPrompt,
@@ -922,4 +924,4 @@ public abstract partial class AssistantBase<TSettings> : AssistantLowerBase wher
     protected virtual void RestoreCustomAssistantSessionState(AssistantSessionStateReader state) { }
 
     #endregion
-}
+}

app/MindWork AI Studio/Assistants/I18N/allTexts.lua

@@ -2797,6 +2797,9 @@ UI_TEXT_CONTENT["AISTUDIO::ASSISTANTS::VISUALBRIEFING::VISUALBRIEFINGFAILUREEXTE
 -- The model response used an unsupported contract version. Please try again or select another model.
 UI_TEXT_CONTENT["AISTUDIO::ASSISTANTS::VISUALBRIEFING::VISUALBRIEFINGFAILUREEXTENSIONS::T921285247"] = "The model response used an unsupported contract version. Please try again or select another model."
 
+-- This chart cannot be displayed: {0}
+UI_TEXT_CONTENT["AISTUDIO::CHAT::CHARTBLOCK::T1070038198"] = "This chart cannot be displayed: {0}"
+
 -- System
 UI_TEXT_CONTENT["AISTUDIO::CHAT::CHATROLEEXTENSIONS::T2402387132"] = "System"
 

app/MindWork AI Studio/Chat/ChartBlock.razor

@@ -0,0 +1,61 @@
+@namespace AIStudio.Chat
+@using MudBlazor
+@inherits AIStudio.Components.MSGComponentBase
+
+@if (this.Result.Chart is { } chart)
+{
+    <div class="chart-block-shell my-3">
+        <MudPaper Class="chart-block" Outlined="true">
+            <MudText Typo="Typo.h6" Class="chart-block-title">@chart.Title</MudText>
+            @if (chart.Type is ChartDefinitionType.TIME_SERIES)
+            {
+                <div class="chart-block-plot chart-block-plot-axis">
+                    <MudTimeSeriesChart ChartSeries="@this.TimeSeriesChartSeries"
+                                        ChartOptions="@this.ChartOptions"
+                                        AxisChartOptions="@this.AxisChartOptions"
+                                        TimeLabelSpacing="@this.TimeLabelSpacing"
+                                        TimeLabelFormat="@this.TimeLabelFormat"
+                                        DataMarkerTooltipTimeLabelFormat="dd-MM-yyyy HH:mm:ss 'UTC'"
+                                        Width="100%"
+                                        Height="350px" />
+                </div>
+            }
+            else if (chart.Type is ChartDefinitionType.PIE or ChartDefinitionType.DONUT)
+            {
+                <div class="chart-block-plot chart-block-plot-circular">
+                    <MudChart ChartType="@this.ChartType"
+                              InputData="@chart.Series[0].Values.ToArray()"
+                              InputLabels="@chart.Categories.ToArray()"
+                              ChartOptions="@this.ChartOptions"
+                              Width="100%"
+                              Height="200px" />
+                </div>
+            }
+            else
+            {
+                <div class="chart-block-plot chart-block-plot-axis">
+                    <MudChart ChartType="@this.ChartType"
+                              ChartSeries="@this.ChartSeries"
+                              XAxisLabels="@chart.Categories.ToArray()"
+                              ChartOptions="@this.CategoryChartOptions"
+                              AxisChartOptions="@this.AxisChartOptions"
+                              Width="100%"
+                              Height="350px" />
+                </div>
+            }
+            @if (chart.Caption is not null)
+            {
+                <MudText Typo="Typo.caption" Align="Align.Center" Class="chart-block-caption d-block">
+                    <em>@chart.Caption</em>
+                </MudText>
+            }
+        </MudPaper>
+    </div>
+}
+else
+{
+    <MudAlert Severity="Severity.Warning" Variant="Variant.Outlined" Class="my-3">
+        @string.Format(T("This chart cannot be displayed: {0}"), this.Result.Error)
+    </MudAlert>
+    <pre class="overflow-auto"><code>@this.Result.RawJson</code></pre>
+}

app/MindWork AI Studio/Chat/ChartBlock.razor.cs

@@ -0,0 +1,99 @@
+using System.Globalization;
+
+using AIStudio.Components;
+using Microsoft.AspNetCore.Components;
+
+namespace AIStudio.Chat;
+
+public partial class ChartBlock : MSGComponentBase
+{
+    private AxisChartOptions AxisChartOptions { get; } = new() { MatchBoundsToSize = true };
+
+    private ChartOptions ChartOptions { get; } = new()
+    {
+        ChartPalette =
+        [
+            "#236A50", "#F2D264", "#79AE90", "#C97857", "#4E7894", "#9B6B8F",
+            "#6A233D", "#6484F2", "#AE7997", "#57A8C9", "#946A4E", "#6B9B77",
+        ],
+    };
+
+    private ChartOptions HeatMapChartOptions { get; } = new()
+    {
+        ChartPalette = ["#236A50", "#79AE90", "#F2D264", "#C97857", "#6A233D"],
+        EnableSmoothGradient = true,
+        YAxisLabelPosition = YAxisLabelPosition.Right,
+        
+    };
+
+    [Parameter]
+    public ChartBlockParseResult Result { get; set; } = ChartBlockParseResult.Invalid(string.Empty, string.Empty);
+
+    private ChartType ChartType => this.Result.Chart?.Type switch
+    {
+        ChartDefinitionType.BAR => ChartType.Bar,
+        ChartDefinitionType.STACKED_BAR => ChartType.StackedBar,
+        ChartDefinitionType.LINE => ChartType.Line,
+        ChartDefinitionType.PIE => ChartType.Pie,
+        ChartDefinitionType.DONUT => ChartType.Donut,
+        ChartDefinitionType.HEATMAP => ChartType.HeatMap,
+        _ => ChartType.Bar,
+    };
+
+    private List<ChartSeries> ChartSeries => this.Result.Chart?.Series
+        .Select(series => new ChartSeries { Name = series.Name, Data = series.Values.ToArray() })
+        .ToList() ?? [];
+
+    private ChartOptions CategoryChartOptions => this.Result.Chart?.Type is ChartDefinitionType.HEATMAP
+        ? this.HeatMapChartOptions
+        : this.ChartOptions;
+
+    private List<TimeSeriesChartSeries> TimeSeriesChartSeries => this.Result.Chart is not { } chart
+        ? []
+        : chart.Series
+            .Select(series => new TimeSeriesChartSeries
+            {
+                Name = series.Name,
+                Data = chart.Categories
+                    .Select((category, index) => new TimeSeriesChartSeries.TimeValue(
+                        DateTimeOffset.Parse(category, CultureInfo.InvariantCulture).UtcDateTime,
+                        series.Values[index]))
+                    .ToList(),
+                IsVisible = true,
+            })
+            .ToList();
+
+    private TimeSpan TimeLabelSpacing
+    {
+        get
+        {
+            var timestamps = this.GetTimeSeriesTimestamps();
+            if (timestamps.Count < 2)
+                return TimeSpan.FromSeconds(1);
+
+            var range = timestamps[^1] - timestamps[0];
+            var intervalCount = Math.Min(timestamps.Count - 1, 8);
+            return TimeSpan.FromTicks(Math.Max(TimeSpan.TicksPerSecond, range.Ticks / intervalCount));
+        }
+    }
+
+    private string TimeLabelFormat
+    {
+        get
+        {
+            var timestamps = this.GetTimeSeriesTimestamps();
+            if (timestamps.Count < 2)
+                return "yyyy-MM-dd HH:mm";
+
+            var range = timestamps[^1] - timestamps[0];
+            if (range <= TimeSpan.FromDays(2))
+                return "MM-dd HH:mm";
+
+            return range <= TimeSpan.FromDays(730) ? "yyyy-MM-dd" : "yyyy";
+        }
+    }
+
+    private List<DateTimeOffset> GetTimeSeriesTimestamps() => this.Result.Chart?.Categories
+        .Select(category => DateTimeOffset.Parse(category, CultureInfo.InvariantCulture).ToUniversalTime())
+        .ToList() ?? [];
+}

app/MindWork AI Studio/Chat/ChartBlock.razor.css

@@ -0,0 +1,55 @@
+.chart-block-shell {
+    --chart-pine: #236a50;
+    --chart-sage: #79ae90;
+    --chart-sun: #f2d264;
+    --chart-mist: #eaf1ec;
+    padding: 0 1.5rem;
+}
+
+.chart-block-shell ::deep .chart-block {
+    position: relative;
+    overflow: hidden;
+    padding: clamp(1rem, 2.5vw, 1.5rem);
+    border-color: color-mix(in srgb, var(--mud-palette-lines-default) 85%, var(--chart-pine));
+    border-radius: 1.25rem;
+    background: var(--mud-palette-surface);
+    background: color-mix(in srgb, var(--mud-palette-surface) 96%, var(--chart-mist));
+    box-shadow: 0 18px 55px rgba(22, 75, 59, .07);
+}
+
+.chart-block-shell ::deep .chart-block::before {
+    position: absolute;
+    inset: 0 0 auto;
+    height: .25rem;
+    background: linear-gradient(90deg, var(--chart-pine), var(--chart-sage), var(--chart-sun));
+    content: "";
+}
+
+.chart-block-shell ::deep .chart-block-title {
+    margin-block-end: 1rem;
+    font-weight: 700;
+    letter-spacing: -.02em;
+}
+
+.chart-block-plot {
+    width: 100%;
+    margin-inline: auto;
+}
+
+.chart-block-plot-circular {
+    max-width: 30rem;
+}
+
+.chart-block-plot-axis {
+    max-width: 56rem;
+}
+
+.chart-block-plot-heatmap {
+    max-width: none;
+}
+
+.chart-block-shell ::deep .chart-block-caption {
+    margin-block-start: .75rem;
+    color: var(--mud-palette-text-secondary);
+    line-height: 1.5;
+}

app/MindWork AI Studio/Chat/ChartBlockParser.cs

@@ -0,0 +1,315 @@
+using System.Text;
+using System.Text.Json;
+
+namespace AIStudio.Chat;
+
+/// <summary>
+/// Parses and validates versioned AI Studio chart blocks without executing their content.
+/// </summary>
+public static class ChartBlockParser
+{
+    private const int MAX_JSON_BYTES = 32 * 1024;
+    private const int MAX_CATEGORIES = 50;
+    private const int MAX_SERIES = 10;
+
+    private static readonly HashSet<string> ROOT_PROPERTIES = ["schema_version", "type", "title", "caption", "data"];
+    private static readonly HashSet<string> DATA_PROPERTIES = ["categories", "series"];
+    private static readonly HashSet<string> SERIES_PROPERTIES = ["name", "values"];
+
+    /// <summary>
+    /// Parses a JSON chart definition and applies the complete local version 1 validation contract.
+    /// </summary>
+    public static ChartBlockParseResult Parse(string json)
+    {
+        if (Encoding.UTF8.GetByteCount(json) > MAX_JSON_BYTES)
+            return ChartBlockParseResult.Invalid(json, "The chart JSON exceeds the 32 KB limit.");
+
+        try
+        {
+            using var document = JsonDocument.Parse(json, new JsonDocumentOptions
+            {
+                AllowTrailingCommas = false,
+                CommentHandling = JsonCommentHandling.Disallow,
+                MaxDepth = 8,
+            });
+
+            var root = document.RootElement;
+            if (root.ValueKind is not JsonValueKind.Object)
+                return ChartBlockParseResult.Invalid(json, "The chart definition must be a JSON object.");
+
+            if (!HasOnlyKnownProperties(root, ROOT_PROPERTIES, out var propertyError))
+                return ChartBlockParseResult.Invalid(json, propertyError);
+
+            if (!TryGetRequiredInt(root, "schema_version", out var schemaVersion) || schemaVersion != 1)
+                return ChartBlockParseResult.Invalid(json, "schema_version must be 1.");
+
+            if (!TryGetRequiredString(root, "type", out var typeText)
+                || !TryParseType(typeText, out var type))
+                return ChartBlockParseResult.Invalid(json, "type must be bar, stacked_bar, line, pie, donut, heatmap, or time_series.");
+
+            if (!TryGetRequiredString(root, "title", out var title) || string.IsNullOrWhiteSpace(title))
+                return ChartBlockParseResult.Invalid(json, "title must be a non-empty string.");
+
+            string? caption = null;
+            if (root.TryGetProperty("caption", out var captionElement))
+            {
+                if (captionElement.ValueKind is not JsonValueKind.String
+                    || string.IsNullOrWhiteSpace(captionElement.GetString()))
+                    return ChartBlockParseResult.Invalid(json, "caption must be a non-empty string when provided.");
+
+                caption = captionElement.GetString();
+            }
+
+            if (!root.TryGetProperty("data", out var data) || data.ValueKind is not JsonValueKind.Object)
+                return ChartBlockParseResult.Invalid(json, "data must be a JSON object.");
+
+            if (!HasOnlyKnownProperties(data, DATA_PROPERTIES, out propertyError))
+                return ChartBlockParseResult.Invalid(json, propertyError);
+
+            if (!TryReadCategories(data, type, out var categories, out var error))
+                return ChartBlockParseResult.Invalid(json, error);
+
+            if (!TryReadSeries(data, categories.Count, out var series, out error))
+                return ChartBlockParseResult.Invalid(json, error);
+
+            if (type is ChartDefinitionType.PIE or ChartDefinitionType.DONUT)
+            {
+                if (series.Count != 1)
+                    return ChartBlockParseResult.Invalid(json, "Pie and donut charts require exactly one series.");
+
+                if (series[0].Values.Any(value => value < 0))
+                    return ChartBlockParseResult.Invalid(json, "Pie and donut chart values must not be negative.");
+            }
+
+            return ChartBlockParseResult.Valid(json, new(schemaVersion, type, title, caption, categories, series));
+        }
+        catch (JsonException exception)
+        {
+            return ChartBlockParseResult.Invalid(json, $"The chart JSON is invalid: {exception.Message}");
+        }
+    }
+
+    private static bool TryReadCategories(
+        JsonElement data,
+        ChartDefinitionType type,
+        out IReadOnlyList<string> categories,
+        out string error)
+    {
+        categories = [];
+        error = string.Empty;
+        if (!data.TryGetProperty("categories", out var element) || element.ValueKind is not JsonValueKind.Array)
+        {
+            error = "data.categories must be an array.";
+            return false;
+        }
+
+        var values = new List<string>();
+        DateTimeOffset? previousTimestamp = null;
+        foreach (var item in element.EnumerateArray())
+        {
+            if (item.ValueKind is not JsonValueKind.String || string.IsNullOrWhiteSpace(item.GetString()))
+            {
+                error = "Every category must be a non-empty string.";
+                return false;
+            }
+
+            var value = item.GetString()!;
+            if (type is ChartDefinitionType.TIME_SERIES)
+            {
+                if (!HasExplicitTimeZone(value) || !item.TryGetDateTimeOffset(out var timestamp))
+                {
+                    error = "Time series categories must be ISO 8601 timestamps with Z or an explicit UTC offset.";
+                    return false;
+                }
+
+                if (previousTimestamp is not null && timestamp <= previousTimestamp.Value)
+                {
+                    error = "Time series categories must be strictly increasing timestamps.";
+                    return false;
+                }
+
+                previousTimestamp = timestamp;
+            }
+
+            values.Add(value);
+            if (values.Count > MAX_CATEGORIES)
+            {
+                error = $"A chart can contain at most {MAX_CATEGORIES} categories.";
+                return false;
+            }
+        }
+
+        if (values.Count == 0)
+        {
+            error = "A chart requires at least one category.";
+            return false;
+        }
+
+        if (type is ChartDefinitionType.TIME_SERIES && values.Count < 2)
+        {
+            error = "A time series chart requires at least two timestamps.";
+            return false;
+        }
+
+        categories = values;
+        return true;
+    }
+
+    private static bool HasExplicitTimeZone(string value)
+    {
+        if (value.EndsWith('Z'))
+            return true;
+
+        if (value.Length < 6)
+            return false;
+
+        var offsetSign = value[^6];
+        return offsetSign is '+' or '-'
+               && char.IsAsciiDigit(value[^5])
+               && char.IsAsciiDigit(value[^4])
+               && value[^3] is ':'
+               && char.IsAsciiDigit(value[^2])
+               && char.IsAsciiDigit(value[^1]);
+    }
+
+    private static bool TryReadSeries(JsonElement data, int categoryCount, out IReadOnlyList<ChartDefinitionSeries> series, out string error)
+    {
+        series = [];
+        error = string.Empty;
+        if (!data.TryGetProperty("series", out var element) || element.ValueKind is not JsonValueKind.Array)
+        {
+            error = "data.series must be an array.";
+            return false;
+        }
+
+        var result = new List<ChartDefinitionSeries>();
+        foreach (var item in element.EnumerateArray())
+        {
+            if (item.ValueKind is not JsonValueKind.Object)
+            {
+                error = "Every series must be a JSON object.";
+                return false;
+            }
+
+            if (!HasOnlyKnownProperties(item, SERIES_PROPERTIES, out error))
+                return false;
+
+            if (!TryGetRequiredString(item, "name", out var name) || string.IsNullOrWhiteSpace(name))
+            {
+                error = "Every series requires a non-empty name.";
+                return false;
+            }
+
+            if (!item.TryGetProperty("values", out var valuesElement) || valuesElement.ValueKind is not JsonValueKind.Array)
+            {
+                error = "Every series requires a values array.";
+                return false;
+            }
+
+            var values = new List<double>();
+            foreach (var valueElement in valuesElement.EnumerateArray())
+            {
+                if (valueElement.ValueKind is not JsonValueKind.Number
+                    || !valueElement.TryGetDouble(out var value)
+                    || !double.IsFinite(value))
+                {
+                    error = "Series values must be finite JSON numbers.";
+                    return false;
+                }
+
+                values.Add(value);
+            }
+
+            if (values.Count != categoryCount)
+            {
+                error = "Every series must contain exactly one value per category.";
+                return false;
+            }
+
+            result.Add(new(name, values));
+            if (result.Count > MAX_SERIES)
+            {
+                error = $"A chart can contain at most {MAX_SERIES} series.";
+                return false;
+            }
+        }
+
+        if (result.Count == 0)
+        {
+            error = "A chart requires at least one series.";
+            return false;
+        }
+
+        series = result;
+        return true;
+    }
+
+    private static bool HasOnlyKnownProperties(JsonElement element, HashSet<string> knownProperties, out string error)
+    {
+        var seenProperties = new HashSet<string>(StringComparer.Ordinal);
+        foreach (var property in element.EnumerateObject())
+        {
+            if (!knownProperties.Contains(property.Name))
+            {
+                error = $"Unknown chart property: {property.Name}.";
+                return false;
+            }
+
+            if (!seenProperties.Add(property.Name))
+            {
+                error = $"Duplicate chart property: {property.Name}.";
+                return false;
+            }
+        }
+
+        error = string.Empty;
+        return true;
+    }
+
+    private static bool TryGetRequiredInt(JsonElement element, string propertyName, out int value)
+    {
+        value = 0;
+        return element.TryGetProperty(propertyName, out var property)
+               && property.ValueKind is JsonValueKind.Number
+               && property.TryGetInt32(out value);
+    }
+
+    private static bool TryGetRequiredString(JsonElement element, string propertyName, out string value)
+    {
+        value = string.Empty;
+        if (!element.TryGetProperty(propertyName, out var property) || property.ValueKind is not JsonValueKind.String)
+            return false;
+
+        value = property.GetString() ?? string.Empty;
+        return true;
+    }
+
+    private static bool TryParseType(string value, out ChartDefinitionType type)
+    {
+        type = value switch
+        {
+            "bar" => ChartDefinitionType.BAR,
+            "stacked_bar" => ChartDefinitionType.STACKED_BAR,
+            "line" => ChartDefinitionType.LINE,
+            "pie" => ChartDefinitionType.PIE,
+            "donut" => ChartDefinitionType.DONUT,
+            "heatmap" => ChartDefinitionType.HEATMAP,
+            "time_series" => ChartDefinitionType.TIME_SERIES,
+            _ => default,
+        };
+
+        return value is "bar" or "stacked_bar" or "line" or "pie" or "donut" or "heatmap" or "time_series";
+    }
+}
+
+/// <summary>
+/// The safe result of parsing a chart block, including the original JSON for fallback display.
+/// </summary>
+public sealed record ChartBlockParseResult(string RawJson, ChartDefinition? Chart, string Error)
+{
+    public bool IsValid => this.Chart is not null;
+
+    public static ChartBlockParseResult Valid(string rawJson, ChartDefinition chart) => new(rawJson, chart, string.Empty);
+
+    public static ChartBlockParseResult Invalid(string rawJson, string error) => new(rawJson, null, error);
+}

app/MindWork AI Studio/Chat/ChartDefinition.cs

@@ -0,0 +1,31 @@
+namespace AIStudio.Chat;
+
+/// <summary>
+/// A renderer-independent, validated chart definition produced by an AI response.
+/// </summary>
+public sealed record ChartDefinition(
+    int SchemaVersion,
+    ChartDefinitionType Type,
+    string Title,
+    string? Caption,
+    IReadOnlyList<string> Categories,
+    IReadOnlyList<ChartDefinitionSeries> Series);
+
+/// <summary>
+/// A named series in a chart definition.
+/// </summary>
+public sealed record ChartDefinitionSeries(string Name, IReadOnlyList<double> Values);
+
+/// <summary>
+/// Chart types supported by version 1 of the AI Studio chart contract.
+/// </summary>
+public enum ChartDefinitionType
+{
+    BAR,
+    STACKED_BAR,
+    LINE,
+    PIE,
+    DONUT,
+    HEATMAP,
+    TIME_SERIES,
+}

app/MindWork AI Studio/Chat/ChatThread.cs

@@ -13,6 +13,36 @@ namespace AIStudio.Chat;
 public sealed record ChatThread
 {
     private static readonly ILogger<ChatThread> LOGGER = Program.LOGGER_FACTORY.CreateLogger<ChatThread>();
+
+    private const string CHART_OUTPUT_INSTRUCTIONS = """
+        When a chart is useful or explicitly requested, you may include one or more complete chart blocks in your normal response. Use exactly this fenced JSON format:
+        ```aistudio-chart
+        {
+          "schema_version": 1,
+          "type": "bar",
+          "title": "Chart title",
+          "caption": "Contextual interpretation of the chart",
+          "data": {
+            "categories": ["A", "B"],
+            "series": [
+              {
+                "name": "Series",
+                "values": [1, 2]
+              }
+            ]
+          }
+        }
+        ```
+        
+        - Supported types are `bar`, `stacked_bar`, `line`, `pie`, `donut`, `heatmap`, and `time_series`.
+        - Every series needs exactly one finite numeric value per category.
+        - Pie and donut charts need exactly one series and non-negative values.
+        - For heatmaps, categories are the columns, series names are the rows, and series values are the cells.
+        - Time series categories must contain at least two strictly increasing ISO 8601 timestamps with `Z` or an explicit UTC offset.
+        - Add a concise caption that correctly contextualizes the chart and may explain the chart's main finding.
+        - Use only the fields shown above.
+        - Keep other explanatory text outside the chart block.
+        """;
     
     /// <summary>
     /// The unique identifier of the chat thread.
@@ -56,6 +86,12 @@ public sealed record ChatThread
     /// </summary>
     public bool IncludeDateTime { get; set; } = false;
 
+    /// <summary>
+    /// Indicates whether the model may emit locally rendered chart blocks.
+    /// False by default so internal structured model requests remain unchanged.
+    /// </summary>
+    public bool AllowChartOutput { get; set; } = false;
+
     /// <summary>
     /// The data source options for this chat thread.
     /// </summary>
@@ -198,23 +234,32 @@ public sealed record ChatThread
         }
         
         LOGGER.LogInformation(logMessage);
-        if(!this.IncludeDateTime)
+        if(this.IncludeDateTime)
+        {
+            //
+            // Prepend the current date and time to the system prompt:
+            //
+            var nowUtc = DateTime.UtcNow;
+            var nowLocal = DateTime.Now;
+            var currentDateTime = string.Create(
+                new CultureInfo("en-US"),
+                $"Today is {nowUtc:dddd, MMMM d, yyyy h:mm tt} (UTC) and {nowLocal:dddd, MMMM d, yyyy h:mm tt} (local time)."
+            );
+
+            systemPromptText = $"""
+                               {currentDateTime}
+
+                               {systemPromptText}
+                               """;
+        }
+
+        if (!this.AllowChartOutput)
             return systemPromptText;
-        
-        //
-        // Prepend the current date and time to the system prompt:
-        //
-        var nowUtc = DateTime.UtcNow;
-        var nowLocal = DateTime.Now;
-        var currentDateTime = string.Create(
-            new CultureInfo("en-US"),
-            $"Today is {nowUtc:dddd, MMMM d, yyyy h:mm tt} (UTC) and {nowLocal:dddd, MMMM d, yyyy h:mm tt} (local time)."
-        );
 
         return $"""
-                {currentDateTime}
-
                 {systemPromptText}
+
+                {CHART_OUTPUT_INSTRUCTIONS}
                 """;
     }
 
@@ -314,4 +359,4 @@ public sealed record ChatThread
         
         return new Tools.ERIClient.DataModel.ChatThread { ContentBlocks = contentBlocks };
     }
-}
+}

app/MindWork AI Studio/Chat/ContentBlockComponent.razor

@@ -105,10 +105,14 @@
                                         {
                                             <MudMarkdown @key="@segment.RenderKey" Value="@segmentContent" Props="Markdown.DefaultConfig" Styling="@this.MarkdownStyling" MarkdownPipeline="Markdown.CHAT_MARKDOWN_PIPELINE" />
                                         }
-                                        else
+                                        else if (segment.Type is MarkdownRenderSegmentType.MATH_BLOCK)
                                         {
                                             <MathJaxBlock @key="@segment.RenderKey" Value="@segmentContent" Class="mb-5" />
                                         }
+                                        else if (segment.ChartResult is not null)
+                                        {
+                                            <ChartBlock @key="@segment.RenderKey" Result="@segment.ChartResult" />
+                                        }
                                     }
                                     @if (textContent.Sources.Count > 0)
                                     {

app/MindWork AI Studio/Chat/ContentBlockComponent.razor.cs

@@ -17,6 +17,7 @@ public partial class ContentBlockComponent : MSGComponentBase, IAsyncDisposable
     private const string HTML_SELF_CLOSING_TAG = "/>";
     private const string CODE_FENCE_MARKER_BACKTICK = "```";
     private const string CODE_FENCE_MARKER_TILDE = "~~~";
+    private const string CHART_CODE_FENCE_LANGUAGE = "aistudio-chart";
     private const string MATH_BLOCK_MARKER_DOLLAR = "$$";
     private const string MATH_BLOCK_MARKER_BRACKET_OPEN = """\[""";
     private const string MATH_BLOCK_MARKER_BRACKET_CLOSE = """\]""";
@@ -336,6 +337,20 @@ public partial class ContentBlockComponent : MSGComponentBase, IAsyncDisposable
             }
 
             var trimmedLine = TrimWhitespace(normalizedSpan[lineStart..lineEnd]);
+            if (activeMathBlockFenceType is MathBlockFenceType.NONE
+                && activeCodeFenceMarker == '\0'
+                && TryGetChartFenceMarker(trimmedLine, out var chartFenceMarker)
+                && TryFindClosingCodeFence(normalizedSpan, nextLineStart, chartFenceMarker, out var chartContentEnd, out var afterChartFence))
+            {
+                AddMarkdownSegment(markdownSegmentStart, lineStart);
+                var (start, end) = TrimLineBreaks(normalizedSpan, nextLineStart, chartContentEnd);
+                var chartJson = normalized.Substring(start, end - start);
+                segments.Add(new(MarkdownRenderSegmentType.CHART, start, end - start, ChartBlockParser.Parse(chartJson)));
+                markdownSegmentStart = afterChartFence;
+                lineStart = afterChartFence;
+                continue;
+            }
+
             if (activeMathBlockFenceType is MathBlockFenceType.NONE && TryUpdateCodeFenceState(trimmedLine, ref activeCodeFenceMarker))
             {
                 lineStart = nextLineStart;
@@ -463,6 +478,48 @@ public partial class ContentBlockComponent : MSGComponentBase, IAsyncDisposable
         return true;
     }
 
+    private static bool TryGetChartFenceMarker(ReadOnlySpan<char> trimmedLine, out char fenceMarker)
+    {
+        fenceMarker = '\0';
+        if (trimmedLine.SequenceEqual($"{CODE_FENCE_MARKER_BACKTICK}{CHART_CODE_FENCE_LANGUAGE}".AsSpan()))
+            fenceMarker = '`';
+        else if (trimmedLine.SequenceEqual($"{CODE_FENCE_MARKER_TILDE}{CHART_CODE_FENCE_LANGUAGE}".AsSpan()))
+            fenceMarker = '~';
+
+        return fenceMarker != '\0';
+    }
+
+    private static bool TryFindClosingCodeFence(ReadOnlySpan<char> text, int searchStart, char fenceMarker, out int contentEnd, out int afterFence)
+    {
+        contentEnd = 0;
+        afterFence = 0;
+        var closingFence = fenceMarker == '`' ? CODE_FENCE_MARKER_BACKTICK : CODE_FENCE_MARKER_TILDE;
+
+        for (var lineStart = searchStart; lineStart < text.Length;)
+        {
+            var lineEnd = lineStart;
+            while (lineEnd < text.Length && text[lineEnd] is not '\r' and not '\n')
+                lineEnd++;
+
+            var nextLineStart = lineEnd;
+            if (nextLineStart < text.Length && text[nextLineStart] == '\r')
+                nextLineStart++;
+            if (nextLineStart < text.Length && text[nextLineStart] == '\n')
+                nextLineStart++;
+
+            if (TrimWhitespace(text[lineStart..lineEnd]).SequenceEqual(closingFence.AsSpan()))
+            {
+                contentEnd = lineStart;
+                afterFence = nextLineStart;
+                return true;
+            }
+
+            lineStart = nextLineStart;
+        }
+
+        return false;
+    }
+
     private static ReadOnlySpan<char> TrimWhitespace(ReadOnlySpan<char> text)
     {
         var start = 0;
@@ -492,6 +549,7 @@ public partial class ContentBlockComponent : MSGComponentBase, IAsyncDisposable
     {
         MARKDOWN,
         MATH_BLOCK,
+        CHART,
     }
 
     private enum MathBlockFenceType
@@ -506,7 +564,7 @@ public partial class ContentBlockComponent : MSGComponentBase, IAsyncDisposable
         public static readonly MarkdownRenderPlan EMPTY = new(string.Empty, []);
     }
 
-    private sealed class MarkdownRenderSegment(MarkdownRenderSegmentType type, int start, int length)
+    private sealed class MarkdownRenderSegment(MarkdownRenderSegmentType type, int start, int length, ChartBlockParseResult? chartResult = null)
     {
         private string? cachedContent;
 
@@ -516,6 +574,8 @@ public partial class ContentBlockComponent : MSGComponentBase, IAsyncDisposable
 
         public int Length { get; } = length;
 
+        public ChartBlockParseResult? ChartResult { get; } = chartResult;
+
         public int RenderKey { get; } = HashCode.Combine(type, start, length);
 
         public string GetContent(string source)

app/MindWork AI Studio/Components/ChatComponent.razor.cs

@@ -817,6 +817,9 @@ public partial class ChatComponent : MSGComponentBase, IAsyncDisposable
             //
         }
 
+        // This is a user-visible chat request. Internal structured LLM requests keep the default disabled.
+        this.ChatThread.AllowChartOutput = true;
+
         var time = DateTimeOffset.Now;
         IContent? lastUserPrompt;
         if (!reuseLastUserPrompt)
@@ -1304,4 +1307,4 @@ public partial class ChatComponent : MSGComponentBase, IAsyncDisposable
     }
 
     #endregion
-}
+}

app/MindWork AI Studio/Plugins/assistants/README.md

@@ -87,6 +87,40 @@ Each assistant plugin lives in its own directory under the assistants plugin roo
   - `LaunchBehavior = "OPEN_WORKSPACE_CHAT_BY_NAME"`
   - `WorkspaceName = "<target workspace name>"`
 - `UI.Type` is always `"FORM"` and `UI.Children` is a list of component tables.
+
+### Chart output
+
+When an assistant is expected to return a chart, include the following instructions in `ASSISTANT.SystemPrompt`. AI Studio validates and renders the block locally; Lua does not generate or render the chart itself.
+
+````text
+When a chart is useful or explicitly requested, you may include one or more complete chart blocks in your normal response. Use exactly this fenced JSON format:
+```aistudio-chart
+{
+  "schema_version": 1,
+  "type": "bar",
+  "title": "Chart title",
+  "caption": "Contextual interpretation of the chart",
+  "data": {
+    "categories": ["A", "B"],
+    "series": [
+      {
+        "name": "Series",
+        "values": [1, 2]
+      }
+    ]
+  }
+}
+```
+
+- Supported types are `bar`, `stacked_bar`, `line`, `pie`, `donut`, `heatmap`, and `time_series`.
+- Every series needs exactly one finite numeric value per category.
+- Pie and donut charts need exactly one series and non-negative values.
+- For heatmaps, categories are the columns, series names are the rows, and series values are the cells.
+- Time series categories must contain at least two strictly increasing ISO 8601 timestamps with `Z` or an explicit UTC offset.
+- Add a concise caption that correctly contextualizes the chart and may explain the chart's main finding.
+- Use only the fields shown above.
+- Keep other explanatory text outside the chart block.
+````
 - Each component table declares `Type`, an optional `Children` array, and a `Props` table that feeds the component’s parameters.
 
 ### Example: Minimal Requirements Assistant Table
@@ -96,7 +130,7 @@ DEPLOYED_USING_CONFIG_SERVER = false
 ASSISTANT = {
     ["Title"] = "",
     ["Description"] = "",
-    ["SystemPrompt"] = "",
+    ["SystemPrompt"] = "", -- request an aistudio-chart block here when the expected result is a chart
     ["SubmitText"] = "",
     ["AllowProfiles"] = true,
     ["LaunchBehavior"] = "OPEN_WORKSPACE_CHAT_BY_NAME",

app/MindWork AI Studio/Plugins/assistants/plugin.lua

@@ -63,11 +63,41 @@ ASSISTANT = {
     },
 }
 
+--[[
+When a chart is useful or explicitly requested, you may include one or more complete chart blocks in your normal response. Use exactly this fenced JSON format:
+```aistudio-chart
+{
+  "schema_version": 1,
+  "type": "bar",
+  "title": "Chart title",
+  "caption": "Contextual interpretation of the chart",
+  "data": {
+    "categories": ["A", "B"],
+    "series": [
+      {
+        "name": "Series",
+        "values": [1, 2]
+      }
+    ]
+  }
+}
+```
+
+- Supported types are `bar`, `stacked_bar`, `line`, `pie`, `donut`, `heatmap`, and `time_series`.
+- Every series needs exactly one finite numeric value per category.
+- Pie and donut charts need exactly one series and non-negative values.
+- For heatmaps, categories are the columns, series names are the rows, and series values are the cells.
+- Time series categories must contain at least two strictly increasing ISO 8601 timestamps with `Z` or an explicit UTC offset.
+- Add a concise caption that correctly contextualizes the chart and may explain the chart's main finding.
+- Use only the fields shown above.
+- Keep other explanatory text outside the chart block.
+]]
+
 -- usage example with the full feature set:
 ASSISTANT = {
     ["Title"] = "<main title of assistant>", -- required
     ["Description"] = "<assistant description>", -- required
-    ["SystemPrompt"] = "<prompt that fundamentally changes behaviour, personality and task focus of your assistant. Invisible to the user>", -- required
+    ["SystemPrompt"] = "<prompt that fundamentally changes behaviour, personality and task focus of your assistant. If the expected result is a chart, include the chart-output instructions above. Invisible to the user>", -- required
     ["SubmitText"] = "<label for submit button>", -- required
     ["AllowProfiles"] = true, -- if true, allows AiStudios profiles; required
     ["LaunchBehavior"] = "<NONE|OPEN_WORKSPACE_CHAT_BY_NAME>", -- optional; when set to OPEN_WORKSPACE_CHAT_BY_NAME the tile opens a chat directly

app/MindWork AI Studio/Plugins/languages/de-de-43065dbc-78d0-45b7-92be-f14c2926e2dc/plugin.lua

@@ -2799,6 +2799,9 @@ UI_TEXT_CONTENT["AISTUDIO::ASSISTANTS::VISUALBRIEFING::VISUALBRIEFINGFAILUREEXTE
 -- The model response used an unsupported contract version. Please try again or select another model.
 UI_TEXT_CONTENT["AISTUDIO::ASSISTANTS::VISUALBRIEFING::VISUALBRIEFINGFAILUREEXTENSIONS::T921285247"] = "Die Modellantwort verwendet eine nicht unterstützte Vertragsversion. Bitte versuchen Sie es erneut oder wählen Sie ein anderes Modell aus."
 
+-- This chart cannot be displayed: {0}
+UI_TEXT_CONTENT["AISTUDIO::CHAT::CHARTBLOCK::T1070038198"] = "Dieses Diagramm kann nicht angezeigt werden: {0}"
+
 -- System
 UI_TEXT_CONTENT["AISTUDIO::CHAT::CHATROLEEXTENSIONS::T2402387132"] = "System"
 

app/MindWork AI Studio/Plugins/languages/en-us-97dfb1ba-50c4-4440-8dfa-6575daf543c8/plugin.lua

@@ -2799,6 +2799,9 @@ UI_TEXT_CONTENT["AISTUDIO::ASSISTANTS::VISUALBRIEFING::VISUALBRIEFINGFAILUREEXTE
 -- The model response used an unsupported contract version. Please try again or select another model.
 UI_TEXT_CONTENT["AISTUDIO::ASSISTANTS::VISUALBRIEFING::VISUALBRIEFINGFAILUREEXTENSIONS::T921285247"] = "The model response used an unsupported contract version. Please try again or select another model."
 
+-- This chart cannot be displayed: {0}
+UI_TEXT_CONTENT["AISTUDIO::CHAT::CHARTBLOCK::T1070038198"] = "This chart cannot be displayed: {0}"
+
 -- System
 UI_TEXT_CONTENT["AISTUDIO::CHAT::CHATROLEEXTENSIONS::T2402387132"] = "System"