GroupDocs.Signature

MCP server that exposes GroupDocs.Signature as AI-callable tools for Claude, Cursor, GitHub Copilot, and other MCP agents.

NuGet NuGet downloads Docker pulls MCP Registry Integration tests License: MIT

Installation

Install in VS Code Install in VS Code Insiders Add to Cursor Codex CLI setup Windsurf setup

One-click installs pre-fill every supported setting: edit the placeholder documents folder after install (output defaults to the same folder); an empty GROUPDOCS_LICENSE_PATH runs in evaluation mode - point it at your license to lift limits.

More clients - ready-made configs for Claude Code, Codex CLI, Visual Studio 2022, Cursor, Windsurf, Cline, and JetBrains Rider live in install/generated/.

Requires .NET 10 SDK.

Run directly with dnx (recommended — no install step):

dnx GroupDocs.Signature.Mcp --yes

Pulls the latest stable release on every invocation. To pin to a specific version (recommended for shared configs and CI), append @<version>:

dnx [email protected] --yes

Or install as a global dotnet tool:

dotnet tool install -g GroupDocs.Signature.Mcp
groupdocs-signature-mcp

Or run via Docker:

docker run --rm -i \
  -v $(pwd)/documents:/data \
  ghcr.io/groupdocs-signature/signature-net-mcp:latest

Native prerequisites

The underlying GroupDocs engine renders signature glyphs (text, QR codes, barcodes) onto document pages via System.Drawing (GDI+). When you run the server natively (via dnx or the global dotnet tool) on Linux or macOS, install the native libgdiplus library and a fonts package first:

Platform	Setup
Windows	Nothing — GDI+ is built into the OS.
Linux	sudo apt-get install -y libgdiplus libfontconfig1 ttf-mscorefonts-installer
macOS	brew install mono-libgdiplus
Docker	Nothing — the image already bundles libgdiplus, libfontconfig1, and ttf-mscorefonts-installer.

Skipping this on Linux/macOS surfaces as DllNotFoundException: libgdiplus in the tool response. The simplest zero-setup option on Linux/macOS is the Docker image.

Available MCP Tools

Tool	Description
Sign	Sign a document with a text, QR code, barcode, or digital certificate signature; saves the signed file as <name>_signed.<ext>
Verify	Verify signatures in a document (text, QR code, barcode, digital, or all) and return a validity report
SearchTextSignatures	Find embedded text signatures (stamps, labels, native text annotations) with optional substring filter
SearchBarcodes	Find barcode signatures (Code39, Code128, EAN, etc.) with optional decoded-text filter and optional inline image
SearchQrCodes	Find QR code signatures with optional decoded-text filter and optional inline image
SearchDigitalSignatures	Find digital certificate signatures and return signer, issuer, serial number, validity status
SearchImageSignatures	Find embedded image signatures (logos, stamp images, picture overlays) and return them as base64 PNGs
GetDocumentInfo	Return file type, page count, size, and per-page dimensions as JSON (no modification)

Example prompts

• "Sign contract.pdf with a QR code containing 'Signed by Alice'"
• "Verify all signatures in agreement.docx and tell me if any failed"
• "Search invoice.pdf for QR codes — return the decoded text and the QR images"
• "Are there any digital signatures in this report.pdf? If so, who signed it?"
• "Add a text signature 'APPROVED' to the bottom-right of every page of policy.pdf"

Licensing

The MCP server itself is MIT; the underlying GroupDocs.Signature engine requires a license for production use. Without one the server runs in evaluation mode:

• Operations run with evaluation limits, and output may carry evaluation notices.
• A single server process can open at most 15 documents; further calls fail with an evaluation-cap error until the server restarts.

To lift the limits, point GROUPDOCS_LICENSE_PATH at your GroupDocs.Total.lic:

• Get a free 30-day temporary license
• Purchase a license | Product page

Configuration

Variable	Description	Default
GROUPDOCS_MCP_STORAGE_PATH	Base folder for input and output files	current directory
GROUPDOCS_MCP_OUTPUT_PATH	(Optional) separate folder for output files	GROUPDOCS_MCP_STORAGE_PATH
GROUPDOCS_LICENSE_PATH	Path to GroupDocs license file	(evaluation mode)

Usage with Claude Desktop

{
  "mcpServers": {
    "groupdocs-signature": {
      "type": "stdio",
      "command": "dnx",
      "args": ["GroupDocs.Signature.Mcp", "--yes"],
      "env": {
        "GROUPDOCS_MCP_STORAGE_PATH": "/path/to/documents"
      }
    }
  }
}

To pin to a specific version, replace "GroupDocs.Signature.Mcp" with "[email protected]" in args. Pinning is recommended for shared / committed configs to avoid surprise upgrades.

Usage with VS Code / GitHub Copilot

NuGet.org generates a ready-to-use mcp.json snippet on the package page. Copy it directly into your .vscode/mcp.json.

Alternatively, add manually to .vscode/mcp.json:

{
  "inputs": [
    {
      "type": "promptString",
      "id": "storage_path",
      "description": "Base folder for input and output files.",
      "password": false
    }
  ],
  "servers": {
    "groupdocs-signature": {
      "type": "stdio",
      "command": "dnx",
      "args": ["GroupDocs.Signature.Mcp", "--yes"],
      "env": {
        "GROUPDOCS_MCP_STORAGE_PATH": "${input:storage_path}"
      }
    }
  }
}

Same pinning rule as above — swap "GroupDocs.Signature.Mcp" for "[email protected]" to lock to a specific release.

Usage with Docker Compose

cd docker
docker compose up

Edit docker/docker-compose.yml to point volumes at your local documents folder.

License

MIT — see LICENSE