GroupDocs.Signature.Mcp

# GroupDocs.Signature MCP Server

MCP server for GroupDocs.Signature — sign, search, and verify document signatures via AI agents.

## Install

- With dnx (.NET 10 SDK, no install step): `dnx GroupDocs.Signature.Mcp@26.9.0 --yes`
- As a global dotnet tool: `dotnet tool install -g GroupDocs.Signature.Mcp` then run `groupdocs-signature-mcp`
- As a Docker container: `docker run --rm -i -v $(pwd)/documents:/data ghcr.io/groupdocs-signature/signature-net-mcp:latest`
- Native prerequisite for native (dnx / global tool) runs on Linux and macOS: install libgdiplus and MS core fonts — `sudo apt-get install -y libgdiplus libfontconfig1 ttf-mscorefonts-installer` on Linux, `brew install mono-libgdiplus` on macOS. Not needed on Windows (GDI+ built in) or in Docker (bundled in the image).

## MCP tools

- 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 (text / QR / barcode / digital / all) and return validity report as JSON
- SearchTextSignatures — find embedded text signatures with optional substring filter
- SearchBarcodes — find barcode signatures (Code39, Code128, EAN, etc.) with optional decoded-text filter; can return inline barcode images
- SearchQrCodes — find QR code signatures with optional decoded-text filter; can return inline QR images
- SearchDigitalSignatures — find digital certificate signatures and return signer, issuer, serial number, validity
- SearchImageSignatures — find embedded image signatures (logos, stamps, picture overlays) and return them as base64 PNGs
- GetDocumentInfo — return file type, page count, size, and per-page dimensions as JSON (read-only)

## Supported formats

PDF, DOCX, XLSX, PPTX, JPEG, PNG, TIFF, and 30+ other document and image formats supported by GroupDocs.Signature.

## Environment variables

- GROUPDOCS_MCP_STORAGE_PATH — base folder for input + output (defaults to current working directory)
- GROUPDOCS_MCP_OUTPUT_PATH — optional, routes output files to a separate folder
- GROUPDOCS_LICENSE_PATH — path to GroupDocs.Total.lic, omit for evaluation mode

## Licensing

The MCP server is MIT; the underlying GroupDocs.Signature engine requires a license for production use. Evaluation mode (no license): 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. Free 30-day temporary license: https://purchase.groupdocs.com/temporary-license/ — purchase: https://purchase.groupdocs.com/pricing/signature/net

## Key links

- NuGet: https://www.nuget.org/packages/GroupDocs.Signature.Mcp
- Repository: https://github.com/groupdocs-signature/GroupDocs.Signature.Mcp
- Docker: ghcr.io/groupdocs-signature/signature-net-mcp and docker.io/groupdocs/signature-net-mcp
- MCP Registry: io.github.groupdocs-signature/groupdocs-signature-mcp
- License: MIT

## Example prompts for AI agents

- "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"