mcp-open-library

# MCP Open Library

[![MCP Registry](https://img.shields.io/badge/dynamic/json?url=https%3A%2F%2Fregistry.modelcontextprotocol.io%2Fv0.1%2Fservers%3Fsearch%3Dio.github.8enSmith%2Fmcp-open-library%26version%3Dlatest&query=%24.servers%5B0%5D.server.version&label=MCP%20Registry&prefix=v&color=blue)](https://registry.modelcontextprotocol.io/v0.1/servers?search=io.github.8enSmith/mcp-open-library)
[![Socket Badge](https://badge.socket.dev/npm/package/mcp-open-library)](https://socket.dev/npm/package/mcp-open-library)
[![Trust Score](https://archestra.ai/mcp-catalog/api/badge/quality/8enSmith/mcp-open-library)](https://archestra.ai/mcp-catalog/8ensmith__mcp-open-library)
[![NPM](https://nodei.co/npm/mcp-open-library.png?mini=true)](https://npmjs.org/package/mcp-open-library)

A Model Context Protocol (MCP) server for the Open Library API that enables AI assistants to search for book and author information.

<a href="https://glama.ai/mcp/servers/@8enSmith/mcp-open-library">
  <img width="380" height="200" src="https://glama.ai/mcp/servers/@8enSmith/mcp-open-library/badge" alt="mcp-open-library MCP server" />
</a>

## Overview

This project implements an MCP server that provides tools for AI assistants to interact with the [Open Library](https://openlibrary.org/). It allows searching the catalogue by title, author, subject and other fields, searching for authors by name, retrieving detailed author information using their Open Library key, and getting URLs for book covers and author photos. The server returns JSON projections of the Open Library responses rather than the raw payloads.

## Features

- **Book Search**: Search across titles, authors, subjects, places, people, publishers and ISBNs, with sorting and paging (`search_books`).
- **Book Search by Title**: Search for books using their title (`get_book_by_title`).
- **Author Search by Name**: Search for authors using their name, with paging (`get_authors_by_name`).
- **Get Author Details**: Retrieve detailed information for a specific author using their Open Library key (`get_author_info`).
- **Get Author Photo**: Get the URL for an author's photo using their Open Library ID (OLID) (`get_author_photo`).
- **Get Book Cover**: Get the URL for a book's cover image using various identifiers (ISBN, OCLC, LCCN, OLID, ID) (`get_book_cover`).
- **Get Book by ID**: Retrieve detailed book information using various identifiers (ISBN, LCCN, OCLC, OLID) (`get_book_by_id`).

Search results are paged — every search tool returns at most `limit` results (default 10, maximum 50) alongside `num_found`, the total number of matches, which you page through with `offset` (maximum 1000). The two cover tools check that an image actually exists and say so when it does not, rather than handing back a URL that resolves to a blank placeholder.

Every tool is a read-only lookup and advertises itself as such with the `readOnlyHint` and `openWorldHint` annotations, which may allow a client to skip the confirmation prompt it shows for tools that could change something. These are hints: the MCP specification has clients treat annotations as untrusted unless the server is trusted, so the confirmation policy is the client's to decide. Failures — an unreachable API, a rejected argument — come back as a tool result flagged `isError`, so an assistant can read what went wrong and correct its next call rather than the request failing outright.

## Installation

### Quick Start

Nothing to install or build. Point an MCP client at the package with `npx` and it
will be fetched on first run:

```json
{
  "mcpServers": {
    "mcp-open-library": {
      "command": "npx",
      "args": ["-y", "mcp-open-library"]
    }
  }
}
```

In Claude Desktop that goes in `claude_desktop_config.json`; other clients use the
same shape. Restart the client and the seven tools below become available.

### MCP Registry

This server publishes to the official MCP Registry as
`io.github.8enSmith/mcp-open-library` from v1.0.3 onwards. Clients that
support the registry can install it by that name.

To inspect the published listing:

```bash
curl "https://registry.modelcontextprotocol.io/v0.1/servers?search=io.github.8enSmith/mcp-open-library"
```

### Manual Installation

```bash
# Clone the repository
git clone https://github.com/8enSmith/mcp-open-library.git
cd mcp-open-library

# Install dependencies
npm install

# Build the project
npm run build
```

## Usage

### Running the Server

  1. Ensure you are running node v22.21.1 (it'll probably work on a newer version of node but this is what Im using for this test). If you have `nvm` installed run `nvm use`.
  2. In the `mcp-open-library` root directory run `npm run build`
  3. Next run `npm run inspector`. Once built, click the URL with the `MCP_PROXY_AUTH_TOKEN` query string parameter to open the Inspector.
  4. In the Inspector, choose 'STDIO' transport
  5. Make sure the command is set to 'build/index.js'
  6. Click the 'Connect' button in the Inspector - you'll now connect to the server
  7. Click 'Tools' in the top right menu bar
  8. Try running a tool e.g. click get_book_by_title
  9. Search for a book e.g. In the title box enter 'The Hobbit' and then click 'Run Tool'. Server will then return book details.

### Using with an MCP Client

This server implements the Model Context Protocol, which means it can be used by any MCP-compatible AI assistant or client e.g. [Claude Desktop](https://modelcontextprotocol.io/quickstart/user). The server exposes the following tools:

- `search_books`: Search the catalogue by any combination of query, title, author, subject, place, person, publisher and ISBN
- `get_book_by_title`: Search for book information by title
- `get_authors_by_name`: Search for author information by name
- `get_author_info`: Get detailed information for a specific author using their Open Library Author Key
- `get_author_photo`: Get the URL for an author's photo using their Open Library Author ID (OLID)
- `get_book_cover`: Get the URL for a book's cover image using a specific identifier (ISBN, OCLC, LCCN, OLID, or ID)
- `get_book_by_id`: Get detailed book information using a specific identifier (ISBN, LCCN, OCLC, or OLID)

**Example `search_books` input:**

```json
{
  "author": "Ursula K. Le Guin",
  "subject": "fantasy",
  "sort": "old",
  "limit": 2
}
```

**Example `search_books` output:**

```json
{
  "num_found": 51,
  "offset": 0,
  "limit": 2,
  "results": [
    {
      "title": "A Wizard of Earthsea",
      "authors": ["Ursula K. Le Guin"],
      "first_publish_year": 1968,
      "open_library_work_key": "/works/OL59798W",
      "edition_count": 87,
      "author_keys": ["OL31353A"],
      "best_edition": {
        "edition_key": "OL5613890M"
      },
      "cover_url": "https://covers.openlibrary.org/b/id/13617691-M.jpg",
      "ratings_average": 3.95,
      "ebook_access": "borrowable"
    }
  ]
}
```

`best_edition` is one specific edition of the work — the one Open Library ranks best for your query — carrying that edition's own identifiers. Search results otherwise identify a **work** (`open_library_work_key`), which no tool accepts, so this is the route from a search hit to a concrete book.

Its `edition_key` is an OLID you can pass straight to `get_book_by_id` for the full edition record, including its complete ISBN arrays:

```json
{ "idType": "olid", "idValue": "OL5613890M" }
```

The `isbn_13` / `isbn_10` fields are omitted where Open Library holds no ISBN for that edition — as in the example above, and roughly a third of results — while `edition_key` is essentially always present. Where an edition lists several ISBNs of one kind, the first is reported; `get_book_by_id` returns them all.

The `search_books` tool accepts the following parameters:

- At least one of `q`, `title`, `author`, `subject`, `place`, `person`, `publisher` or `isbn` — the request is rejected without one, since an unfiltered search matches the entire catalogue. `q` takes a free-form Solr query such as `subject:cyberpunk AND first_publish_year:[1980 TO 1990]`
- `language`: Optional 3-letter MARC language code (e.g. `eng`, `fre`)
- `sort`: Optional ordering — `new`, `old`, `random`, `key`, `rating`, `readinglog`, `want_to_read`, `currently_reading`, `already_read` or `title`. Omit for relevance
- `limit`: Optional, 1–50, defaults to 10
- `offset`: Optional, 0–1000, defaults to 0

**Example `get_book_by_title` input:**

```json
{
  "title": "The Hobbit",
  "limit": 1
}
```

**Example `get_book_by_title` output:**

```json
{
  "num_found": 224,
  "offset": 0,
  "limit": 1,
  "results": [
    {
      "title": "The Hobbit",
      "authors": ["J.R.R. Tolkien"],
      "first_publish_year": 1937,
      "open_library_work_key": "/works/OL27482W",
      "edition_count": 481,
      "author_keys": ["OL26320A"],
      "best_edition": {
        "edition_key": "OL51709286M",
        "isbn_13": "9780395520215",
        "isbn_10": "0395520215"
      },
      "cover_url": "https://covers.openlibrary.org/b/id/14627509-M.jpg",
      "ratings_average": 4.29,
      "ebook_access": "borrowable"
    }
  ]
}
```

**Example `get_authors_by_name` input:**

```json
{
  "name": "J. R. R. Tolkien",
  "limit": 2
}
```

**Example `get_authors_by_name` output:**

Each result's `key` can be passed to `get_author_info` for that author's full
record. `alternate_names` is abridged here.

```json
{
  "num_found": 2,
  "offset": 0,
  "limit": 2,
  "results": [
    {
      "key": "OL26320A",
      "name": "J.R.R. Tolkien",
      "alternate_names": ["John Ronald Reuel Tolkien", "Tolkien"],
      "birth_date": "3 January 1892",
      "top_work": "The Hobbit",
      "work_count": 355
    },
    {
      "key": "OL332676A",
      "name": "J. R. R. Tolkien Centenary Conference (1992 Keble College, Oxford)",
      "top_work": "Proceedings of the J.R.R. Tolkien Centenary Conference, 1992",
      "work_count": 2
    }
  ]
}
```

**Example `get_author_info` input:**

```json
{
  "author_key": "OL26320A"
}
```

**Example `get_a