The full upstream README, mirrored here for reference. Install config, tool schemas, adoption signals, and an original overview live on the Eth Library MCP listing page.
🇨🇭 Part of the Swiss Public Data MCP Portfolio
🌐 English | Deutsch
MCP server giving AI models direct access to 30M+ resources at ETH Library Zurich – books, maps, images and archival material.
eth-library-mcp connects AI assistants like Claude to the largest natural-science library in Switzerland. It exposes full-text search, archive-level queries and resource-type filtering via the ETH Library's Discovery API – all through a single, standardised MCP interface.
6 Tools · 1 API · 2 Resources · 2 Prompts
MCP Protocol Version: 2026-07-28 (via mcp[cli]>=2.0.0,<3).
BUG-02 is resolved — by removing the tool.
eth_search_personswas documented as "currently non-functional, correct URL to be verified". It has now been verified, and there is no correct URL: the Persons API is gone from the gateway, not merely locked. The gateway routes before it checks the API key, so an existing route answers401and a missing one answers404—/discovery/v1/resourcesgives 401, every/persons/v1/*path gives 404, and so does a deliberately invented Discovery path used as a control. Offering a capability that cannot exist is the same mistake as returning an empty result, only louder. The measurement is recorded and dated intests/fixtures/api_routes.json.
Anchor demo query: "Find historical documents about Zurich school history in the ETH Library archives."
Without an API key the server returns a helpful error message with the registration link – no crashes.
Try it immediately in Claude Desktop:
"Find books about Swiss education history in the ETH Library." "Search the Max Frisch archive for manuscripts about Zurich."
→ More use cases by audience →
| Variable | Description | Required |
|---|---|---|
ETH_LIBRARY_API_KEY | API key for Discovery & Persons API | ✅ |
ETH_LIBRARY_LOG_LEVEL | Log level (DEBUG/INFO/WARNING/ERROR), default INFO | — |
ETH_LIBRARY_CORS_ORIGINS | Comma-separated CORS allow-origins for --http. Empty by default: no browser client is permitted. * allows any origin and is logged as a warning. Does not affect stdio clients. | — |
ETH_LIBRARY_ALLOWED_HOSTS | Comma-separated hostnames this server is reachable under. Required for a non-loopback bind (--host 0.0.0.0): the process cannot derive its own public name, and without this the SDK answers 421 Invalid Host header to every request. Empty by default; loopback stays reachable either way. | — |
Config file locations:
~/Library/Application Support/Claude/claude_desktop_config.json%APPDATA%\Claude\claude_desktop_config.jsonFor use via claude.ai in the browser (e.g. on managed workstations without local software):
The HTTP transport binds to 127.0.0.1 by default. To expose it on another
interface, pass --host explicitly:
⚠️ Do not bind to
0.0.0.0without a reverse proxy. The server has no built-in auth, rate-limiting or TLS — any LAN neighbour could call your tools.
💡 "stdio for the developer laptop, HTTP for the browser — behind a proxy."
| Tool | Description |
|---|---|
eth_search_resources | Full-text search over 30M+ resources with fields, operators, facets |
eth_get_resource | Full metadata for a specific resource via MMS-ID |
eth_search_archive | Search within a specific archive (University Archives, Max Frisch, Thomas Mann, etc.) |
eth_search_by_type | Filter by resource type (books, maps, images, archival material, etc.) |
eth_search_education | Curated search for education topics (pedagogy, school history, etc.) |
| Tool | Description |
|---|
| Tool | Description |
|---|---|
eth_library_info | Server overview: all types and archives at a glance |
| Item | Type | Description |
|---|---|---|
eth://resource-types | Resource | All available resource types |
eth://archives | Resource | All available archives and collections |
research-workflow | Prompt | Structured research workflow |
education-research | Prompt | Education topics workflow (Schulamt-optimised) |
The Discovery API uses structured queries:
| Field | Meaning |
|---|---|
any | All fields (recommended for starters) |
title | Title only |
creator | Author / creator |
sub | Subject headings / topics |
| Operator | Meaning |
|---|---|
contains | Term is present |
exact | Exact match |
begins_with | Starts with |
Examples:
| Identifier | Description |
|---|---|
ETH_Hochschularchiv | Institutional memory of ETH Zurich |
ETH_MaxFrischArchiv | Estate of Swiss author Max Frisch |
ETH_ThomasMannArchiv | Letters and documents of Thomas Mann |
ETH_GraphischeSammlung | Prints, drawings, graphic works |
ETH_Bildarchiv | Science/technology history, Swissair (E-Pics) |
| Query | Tool |
|---|---|
| "Find books about Zurich school history" | eth_search_education |
| "What's in the Max Frisch archive?" | eth_search_archive |
| "Find historical maps of Switzerland" | eth_search_by_type |
| "Get full metadata for resource ID 991170525863705501" | eth_get_resource |
| "Which archives does the ETH Library hold?" | eth_library_info |
This server speaks two protocol eras over the same endpoint. The client's first request on a connection decides which one applies; a later claim from the other era is refused.
| Era | Revision | Who reaches it |
|---|---|---|
initialize handshake | 2024-11-05 … 2025-11-25 | What today's clients speak. The server answers with the revision asked for, or with the 2025-11-25 ceiling when the request asks for something newer. |
| Per-request envelope | 2026-07-28 | A request carrying the 2026-07-28 _meta envelope opens a modern connection. |
Both revisions are pinned in
tests/test_protocol_version.py and asserted
against the installed SDK, so a Dependabot bump of mcp cannot move either one
silently. The handshake ceiling is measured against a live initialize through
the assembled ASGI stack, not read off a constant name.
Note that the SDK's LATEST_PROTOCOL_VERSION is an alias for the modern
era, not for the handshake era — pinning against it alone would leave the era
that current clients actually negotiate free to drift.
Update policy. When the gate fails, do not edit the constant blindly: read
the spec changelog between the two revisions, verify the server still behaves,
then move the constant, this section, README.de.md and
CHANGELOG.md together.
Until 2026-08-08 this repository had no live tests at all — pytest -m live
collected zero. Nothing in it had ever been held against the source.
The Discovery payloads still cannot be recorded: the API requires a key, and
tests/fixtures/PROVENANCE.md lists them explicitly as NOT RECORDED rather
than giving them a date they never had. What is recordable is the contract the
source gives up without a key — which routes the gateway serves — and that is
exactly what the finding hangs on. The two control_* entries are part of the
measurement, not decoration: without them the recording only proves that someone
got a 404; with them it proves what the gateway distinguishes.
The two live tests need no key and say something anyway: they report if the Persons API comes back (then the tool should return) or if Discovery loses its route (then five tools are affected).
ETH_LIBRARY_API_KEY environment variable and never logged or transmitted to third parties.limit and offset parameters conservatively.Contributions are welcome! See CONTRIBUTING.md (Deutsch) for guidelines.
Read-only, no PII, a single upstream API key, and a fixed egress allow-list of ETH Library endpoints. See SECURITY.md (Deutsch) for the full security posture and accepted-risk decisions.
See CHANGELOG.md
Hayal Oezkan · github.com/malkreide
Powered by Model Context Protocol • 1 API • 6 Tools • 2 Resources • 2 Prompts
Run via uv's uvx — no clone or manual install needed. Add to your MCP client config (mcpServers for Claude Desktop, Cursor and Windsurf; use a top-level servers key for VS Code in .vscode/mcp.json):