arolsen-mcp

MCP server exposing search and document retrieval against the Arolsen Archives online collection — a German archive of documents on Nazi persecution.

Install

The published package on npm is the recommended path. In Claude Desktop or Claude Code, add this MCP server entry:

{
  "mcpServers": {
    "arolsen": {
      "command": "npx",
      "args": ["-y", "arolsen-mcp@latest"]
    }
  }
}

For Claude Desktop, the config file lives at ~/Library/Application Support/Claude/claude_desktop_config.json (macOS).

Develop locally

git clone https://github.com/wspringer/arolsen-mcp
cd arolsen-mcp
npm install
npm run build

Then point your MCP client at the local build:

{
  "mcpServers": {
    "arolsen": {
      "command": "node",
      "args": ["/absolute/path/to/arolsen-mcp/dist/index.js"]
    }
  }
}

Tools

| Tool | Purpose | |---|---| | arolsen_search(query, syn_search?) | Run a search; returns counts + an opaque cursor. | | arolsen_search_results(cursor, kind, order_by?) | Paginate persons or archive units (opaque next_cursor). | | arolsen_get_archive_unit(desc_id) | Full metadata + breadcrumb for an archive unit. | | arolsen_get_documents_in_unit(desc_id, offset?) | Image-bearing documents inside a unit. Uses offset / next_offset (numeric) because the upstream call is stateless. | | arolsen_get_document(doc_id) | All page images of a single document. |

Notes on the upstream

Arolsen does not publish an official API. This server reverse-engineers the Angular SPA's ITS-WS.asmx JSON endpoints. Schema drift will break the server; tests use captured fixtures so changes fail loudly.

Terms of use

Arolsen's Terms of Use prohibit "integrating digital versions into another archive without consent of the Arolsen Archives" and require citation. This MCP server is a search client (a query UI), not a republishing system; it does not redistribute or re-archive content. If you intend any redistribution, contact Arolsen Archives first.

Tests

npm test           # unit tests against captured fixtures
npm run smoke      # one live request against the Arolsen API