GroupDocs.Signature.Mcp

# GroupDocs.Signature MCP Server

MCP server that exposes [GroupDocs.Signature](https://products.groupdocs.com/signature) as AI-callable tools
for Claude, Cursor, GitHub Copilot, and other MCP agents.

[![NuGet](https://img.shields.io/nuget/v/GroupDocs.Signature.Mcp?label=NuGet)](https://www.nuget.org/packages/GroupDocs.Signature.Mcp)
[![NuGet downloads](https://img.shields.io/nuget/dt/GroupDocs.Signature.Mcp?label=downloads)](https://www.nuget.org/packages/GroupDocs.Signature.Mcp)
[![Docker pulls](https://img.shields.io/docker/pulls/groupdocs/signature-net-mcp?label=docker%20pulls)](https://hub.docker.com/r/groupdocs/signature-net-mcp)
[![MCP Registry](https://img.shields.io/badge/MCP_Registry-listed-6f42c1)](https://registry.modelcontextprotocol.io/v0/servers?search=io.github.groupdocs-signature/groupdocs-signature-mcp)
[![Integration tests](https://github.com/groupdocs-signature/GroupDocs.Signature.Mcp.Tests/actions/workflows/integration.yml/badge.svg)](https://github.com/groupdocs-signature/GroupDocs.Signature.Mcp.Tests/actions/workflows/integration.yml)
[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)

<!-- TODO(manual): record 30s demo per improvement-plan M1 -->
<!-- ![Demo](assets/demo.gif) -->

## Installation

Requires [.NET 10 SDK](https://dotnet.microsoft.com/download/dotnet/10.0).

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

```bash
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>`:

```bash
dnx GroupDocs.Signature.Mcp@26.7.1 --yes
```

<!-- install-buttons:start - generated by install/generate-install-links.ps1; do not edit by hand -->
[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF)](https://vscode.dev/redirect/mcp/install?name=groupdocs-signature&inputs=%5B%7B%22type%22%3A%22promptString%22%2C%22id%22%3A%22storage_path%22%2C%22description%22%3A%22Base%20folder%20for%20input%20and%20output%20files%22%7D%2C%7B%22type%22%3A%22promptString%22%2C%22id%22%3A%22license_path%22%2C%22description%22%3A%22Path%20to%20GroupDocs%20license%20file%20%28optional%20-%20evaluation%20mode%20if%20empty%29%22%7D%5D&config=%7B%22command%22%3A%22dnx%22%2C%22args%22%3A%5B%22GroupDocs.Signature.Mcp%22%2C%22--yes%22%5D%2C%22env%22%3A%7B%22GROUPDOCS_MCP_STORAGE_PATH%22%3A%22%24%7Binput%3Astorage_path%7D%22%2C%22GROUPDOCS_LICENSE_PATH%22%3A%22%24%7Binput%3Alicense_path%7D%22%7D%7D) [![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5)](https://insiders.vscode.dev/redirect/mcp/install?name=groupdocs-signature&inputs=%5B%7B%22type%22%3A%22promptString%22%2C%22id%22%3A%22storage_path%22%2C%22description%22%3A%22Base%20folder%20for%20input%20and%20output%20files%22%7D%2C%7B%22type%22%3A%22promptString%22%2C%22id%22%3A%22license_path%22%2C%22description%22%3A%22Path%20to%20GroupDocs%20license%20file%20%28optional%20-%20evaluation%20mode%20if%20empty%29%22%7D%5D&config=%7B%22command%22%3A%22dnx%22%2C%22args%22%3A%5B%22GroupDocs.Signature.Mcp%22%2C%22--yes%22%5D%2C%22env%22%3A%7B%22GROUPDOCS_MCP_STORAGE_PATH%22%3A%22%24%7Binput%3Astorage_path%7D%22%2C%22GROUPDOCS_LICENSE_PATH%22%3A%22%24%7Binput%3Alicense_path%7D%22%7D%7D&quality=insiders) [![Add to Cursor](https://img.shields.io/badge/Cursor-Add_MCP-111111)](https://cursor.com/en/install-mcp?name=groupdocs-signature&config=eyJjb21tYW5kIjoiZG54IiwiYXJncyI6WyJHcm91cERvY3MuU2lnbmF0dXJlLk1jcCIsIi0teWVzIl0sImVudiI6eyJHUk9VUERPQ1NfTUNQX1NUT1JBR0VfUEFUSCI6Ii9wYXRoL3RvL2RvY3VtZW50cyJ9fQ%3D%3D)

> One-click buttons prompt for your documents folder (and optional license). Cursor's
> deeplink installs with a placeholder storage path - edit it after install.
<!-- install-buttons:end -->

> **More clients** — ready-made configs for Claude Code, Visual Studio 2022 (`.mcp.json`),
> Cursor, Windsurf, Cline, and JetBrains Rider live in [`install/generated/`](install/generated/).

**Or install as a global dotnet tool:**

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

**Or run via Docker:**

```bash
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](https://purchase.groupdocs.com/temporary-license/)
- [Purchase a license](https://purchase.groupdocs.com/pricing/signature/net) | [Product page](https://products.groupdocs.com/signature/net/)

## 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

```json
{
  "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
> `"GroupDocs.Signature.Mcp@26.7.1"` 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](https://www.nuget.org/packages/GroupDocs.Signature.Mcp).
Copy it directly into your `.vscode/mcp.json`.

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

```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
> `"GroupDocs.Signature.Mcp@26.7.1"` to lock to a specific release.

## Usage with Docker Compose

```bash
cd docker
docker compose up
```

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

## License

MIT — see [LICENSE](LICENSE)

<!-- mcp-name: io.github.groupdocs-signature/groupdocs-signature-mcp -->