Implement translate-document tool for translating documents via the DeepL API

[j-christl]

Context

So far, only the text translation and text rephrasing functionality of DeepL is exposed via MCP tools.
This change adds a tool for translating documents via the DeepL API. This allows the user/LLM to translate documents such as *.pdf, *.docx and more (see "Document Formats" resource below).

Example usage

Request:

Please translate this file into german (de): /Users/myuser/Downloads/my_document.pdf

Response:

[...]
Perfect! ✅ Your PDF has been successfully translated from the original language to German. The translated document has been saved as /tmp/my_document de.pdf.

Limitations

Currently, Claude cannot transmit files via the MCP protocol that have been drag&dropped into Claude Desktop. Hence, this implementation depends on the user specifying the path of the file, rather than drag&dropping the file into Claude Desktop.

Resources

• Official Node.js Client Library for the DeepL API: https://github.com/DeepLcom/deepl-node
• DeepL Document Translation API: https://developers.deepl.com/docs/api-reference/document
• Document formats: https://support.deepl.com/hc/en-us/articles/360020582359-Document-formats

[morsssss]

Sorry - I didn't realize that no one had looked at your PR!

So... I wonder if we could support files in a more natural way, via one of two mechanisms:

• files brought into the flow from use of a tool like https://github.com/modelcontextprotocol/servers/tree/main/src/filesystem . In such a case, we'd get the file from their read_text_file, read_media_file, or read_multiple_files methods. Not sure whether this would be a common use case, but for users who'd installed a filesystem tool, we'd enable them to ask their AI client something like "Can you find that file in my Downloads folder that has Greek in it, and translate that into Spanish?"

• This resource, at least, tells us that LLMs have various ways of working with files. It does talk about Claude's way in particular.

Are you up for investigating either of these?