MatPlotLibNet.Mcp 1.18.0

.NET 10.0

{
  "inputs": [
    {
      "type": "promptString",
      "id": "MATPLOTLIBNET_MCP_OUTPUT_ROOT",
      "description": "The only directory save_chart may write under. Defaults to the system temp directory."
    },
    {
      "type": "promptString",
      "id": "MATPLOTLIBNET_FONTS",
      "description": "Font files (.ttf, .otf) and directories of them, separated by ';', registered at startup so a chart can use a script the bundled font lacks (Devanagari, Thai, Chinese). Arabic and Hebrew work without it."
    }
  ],
  "servers": {
    "matplotlibnet.mcp": {
      "type": "stdio",
      "command": "dnx",
      "args": ["matplotlibnet.mcp@1.18.0", "--yes"],
      "env": {
        "MATPLOTLIBNET_MCP_OUTPUT_ROOT": "${input:MATPLOTLIBNET_MCP_OUTPUT_ROOT}",
        "MATPLOTLIBNET_FONTS": "${input:MATPLOTLIBNET_FONTS}"
      }
    }
  }
}

This package contains an MCP Server. The server can be used in VS Code by copying the generated JSON to your VS Code workspace's .vscode/mcp.json settings file.

dotnet tool install --global MatPlotLibNet.Mcp --version 1.18.0

This package contains a .NET tool you can call from the shell/command line.

dotnet new tool-manifest
                    

                            if you are setting up this repo

dotnet tool install --local MatPlotLibNet.Mcp --version 1.18.0

This package contains a .NET tool you can call from the shell/command line.

#tool dotnet:?package=MatPlotLibNet.Mcp&version=1.18.0

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

nuke :add-package MatPlotLibNet.Mcp --version 1.18.0

The NuGet Team does not provide support for this client. Please contact its maintainers for support.

MatPlotLibNet.Mcp

mcp-name: io.github.xkqg/matplotlibnet

An MCP (Model Context Protocol) server for MatPlotLibNet. It gives an AI agent (Claude Code, VS Code, Claude Desktop, or any other MCP host) five tools:

tool	what it does
`render_chart`	renders a chart spec to a PNG image the model can look at
`save_chart`	writes the chart as PNG, SVG or PDF to a file and returns the path it wrote
`chart_data_table`	returns the chart's data as markdown tables the model can read, and the same values as structured content it can compute with
`list_chart_types`	lists the chart types the spec accepts; the list is read from the library's own registry
`describe_chart_schema`	describes the fields of the spec and gives a worked example for a chart type

The server communicates over stdio. It is a .NET tool: a host runs it with dnx MatPlotLibNet.Mcp (the .NET 10 SDK resolves and starts it), or with dotnet tool exec MatPlotLibNet.Mcp.

{
  "servers": {
    "MatPlotLibNet.Mcp": {
      "type": "stdio",
      "command": "dnx",
      "args": ["MatPlotLibNet.Mcp", "--yes"]
    }
  }
}

The spec

The spec is the library's own figure JSON: the same document that figure.ToJson() writes and ChartSerializer.FromJson reads. The agent can therefore ask for any chart the library can draw:

{
  "width": 800, "height": 600, "title": "Revenue",
  "subPlots": [{
    "series": [{ "type": "line", "xData": [1, 2, 3, 4, 5], "yData": [2, 4, 3, 5, 1], "label": "Q1" }]
  }]
}

The server validates the spec before it renders. It rejects an unknown field, an unknown chart type, a misspelled enum value, a colour the library does not know, or a missing size. The error message names the field that is wrong, so the model can correct the spec instead of receiving a blank picture.

What comes back

render_chart returns the PNG as an image block. Beside it, it returns a short text summary (chart types, series, axis ranges), so a model that cannot see the image still knows what it made. SVG and PDF output is large, so it goes to a file through save_chart and is never returned inline.

The SVG this server writes stores text as glyph outlines (<path>), not as <text> elements. This is because the PNG backend is loaded in the same process, and the library then embeds its own font so that the drawing is identical everywhere.

Limits

save_chart writes only under one directory: the system temp directory, or the one named by the MATPLOTLIBNET_MCP_OUTPUT_ROOT environment variable. It never overwrites an existing file unless asked.
Arabic and Hebrew text work without setup. For Devanagari, Thai, Chinese, Japanese or Korean, name font files or directories of font files in the MATPLOTLIBNET_FONTS environment variable, separated by ;; they are registered when the server starts. A bad entry is logged and skipped.
The server refuses a canvas larger than the documented ceiling, and the error message states the ceiling.

License

MIT — see the repository.

Product	Compatible and additional computed target framework versions.
.NET	net10.0 is compatible. net10.0-android was computed. net10.0-browser was computed. net10.0-ios was computed. net10.0-maccatalyst was computed. net10.0-macos was computed. net10.0-tvos was computed. net10.0-windows was computed.

Compatible target framework(s)

Included target framework(s) (in package)

Learn more about Target Frameworks and .NET Standard.

This package has no dependencies.

Version	Downloads	Last Updated
1.18.0	0	9/23/2026
1.17.1	93	9/13/2026
1.17.0	135	9/12/2026
1.16.0	111	9/12/2026
1.15.1	106	9/12/2026
1.15.0	105	9/11/2026

MatPlotLibNet 1.18.0. What changed in this release, and in every release before it, is written out in the changelog: https://github.com/xkqg/MatPlotLibNet/blob/main/CHANGELOG.md#1180