Alexandria

A Model Context Protocol (MCP) server for querying, reading, and ingesting texts from 61 public digital libraries. Works with any MCP-compatible client (Claude Desktop, Cursor, VS Code Copilot, etc.).

Tools

Tool	Description
library_list_sources	List all 61 sources with descriptions and full-text capabilities
library_ask(query, max_sources?, results_per_source?)	Natural language search — routes your query to the best sources, searches in parallel, returns unified deduplicated results
library_search(query, source, limit?)	Search a specific source by title, author, or keywords
library_read(id, source)	Fetch full text or metadata for an item (200k char limit)
library_index(id, source)	Dry run: chunk and score text quality without writing anything
library_ingest(id, source)	Chunk → embed → store in your vector database. Idempotent.
library_recommend(id, limit?)	Get similar papers via Semantic Scholar's recommendation engine (up to 500)

library_ask is the primary entry point. library_search is for targeted queries against a known source. library_index / library_ingest are for building a vector knowledge base from retrieved texts.

Sources (61)

Public Domain Literature (29)

Source	Coverage	Full Text
gutenberg	76k+ public domain books	Yes
openlibrary	30M+ records	Metadata only
archive	41M+ texts, newspapers, scanned books	Yes
sacredtexts	Curated registry: Quran, Sufi corpus, Vedanta, Buddhism, Taoism, Hermeticism, Christian mysticism	Yes (scraped)
wikisource	Free-content library: historical documents, literary works	Yes
standardebooks	Carefully formatted, public domain ebooks	Yes
perseus	Classical Greek and Latin texts with translations	Yes
ctext	Chinese Text Project — pre-modern Chinese literature	Yes
gallica	Bibliothèque nationale de France — French heritage texts	Yes
loc	Library of Congress — US historical collections	Metadata only
hathitrust	17M+ volumes from research libraries	Metadata only
dpla	Digital Public Library of America — US cultural heritage	Metadata only
ndl	National Diet Library Japan	Metadata only
europeana	European cultural heritage — 50M+ objects	Metadata only
trove	National Library of Australia — newspapers, books, images	Yes
bhl	Biodiversity Heritage Library — natural history literature	Yes
digitalnz	National Library of New Zealand	Metadata only
internetclassics	Internet Classics Archive — 441 classical works	Yes
marxists	Marxists Internet Archive — political theory, philosophy	Yes
projectruneberg	Nordic literature and history	Yes
cervantes	Biblioteca Virtual Miguel de Cervantes — Spanish literature	Yes
doab	Directory of Open Access Books — 70k+ peer-reviewed OA books	Metadata only
oapen	Open Access Publishing in European Networks — humanities & social sciences	Yes
googlebooks	Google Books — metadata and preview snippets	Metadata only
chroniclingamerica	Library of Congress — US historic newspapers 1770–1963	Yes
ccel	Christian Classics Ethereal Library	Yes
feedbooks	Public domain and self-published ebooks	Yes
wdl	World Digital Library — international manuscripts and maps	Metadata only
datagov	Data.gov — US government open data catalog	Metadata only

Academic & Science (11)

Source	Coverage	Full Text
arxiv	2M+ preprints: physics, math, CS, biology, economics	Yes
core	57M+ open access research papers across all disciplines	Yes
europmc	Europe PubMed Central — life sciences literature	Yes
nasa	NASA Technical Reports Server	Yes
osti	DOE Office of Scientific and Technical Information	Yes
eric	Education Resources Information Center	Yes
nsf	NSF Award Search — funded research abstracts	Yes
courtlistener	US federal and state court opinions (Free Law Project). 125 req/day.	Yes
biorxiv	bioRxiv preprints — biology	Yes
zenodo	CERN open repository — papers, datasets, software. 2M+ records.	Yes
semanticscholar	Semantic Scholar — 200M+ papers with AI-powered metadata	Yes

Government, Law & International (5)

Source	Coverage	Full Text
govinfo	US Government Publishing Office — laws, regulations, congressional records	Yes
nih	NIH Office of Portfolio Analysis	Yes
nbnorway	National Library of Norway	Metadata only
legislation	legislation.gov.uk — UK Acts and Statutory Instruments	Yes
osf	Open Science Framework — preprints and research data	Yes

Specialized Corpora (3)

Source	Coverage	Full Text
earlyprint	Early English print 1473–1700	Yes
openiti	OpenITI — Arabic/Persian Islamic texts (GitHub-based)	Yes
legislationscot	Scottish legislation	Yes

Research Aggregators (8)

Source	Coverage	Full Text
openalex	OpenAlex — 240M+ scholarly works, open catalog	Metadata only
plos	PLOS journals — open access science	Yes
crossref	Crossref — 150M+ DOI metadata records	Metadata only
nasaads	NASA Astrophysics Data System	Yes
smithsonian	Smithsonian Institution — collections and research	Metadata only
doaj	Directory of Open Access Journals — 20k+ journals	Metadata only
nara	National Archives — US federal records	Metadata only
springer	SpringerNature — OA and metadata	Metadata only

Institutional Repositories (4)

Source	Coverage	Full Text
harvardlib	Harvard Library Digital Collections	Metadata only
apollo	Cambridge University repository	Yes
ora	Oxford Research Archive	Yes
base	Bielefeld Academic Search Engine — 300M+ documents (pending IP whitelist)	Metadata only

Software Documentation (1)

Source	Coverage	Full Text
codewiki	Google Code Wiki — open source project documentation	Yes

Credentials

Most tools query external library APIs directly and need no credentials at all. The two optional dependencies are scoped to specific tools:

OpenAI — optional (platform.openai.com)

Required by two tools only:

• library_ask — uses gpt-4o-mini to route your natural language query to the right sources and generate optimized per-source search terms. Without this key, use library_search to query sources directly.
• library_ingest — uses text-embedding-3-small to embed chunked text before writing to the vector store.

library_list_sources, library_search, library_read, library_index, and library_recommend all work without an OpenAI key.

Supabase — optional (supabase.com)

Required by one tool only:

• library_ingest — writes chunked, embedded text into a pgvector table for semantic search. Without this, retrieved texts stay in-context and are not persisted anywhere.

Everything else — searching, reading, browsing, getting recommendations — queries external sources in real time and needs no database.

Source-specific keys

Some sources require their own API key. These are free registrations. Sources without a key listed here work without any credentials.

Env Var	Source(s)	Get It
CORE_API_KEY	core	core.ac.uk/services/api
COURTLISTENER_API_KEY	courtlistener	courtlistener.com/profile/tokens
GOVINFO_API_KEY	govinfo, smithsonian	api.data.gov/signup — one key covers both
GOOGLE_BOOKS_API_KEY	googlebooks	Google Cloud Console → APIs & Services → Books API
BHL_API_KEY	bhl	biodiversitylibrary.org/getapikey
DIGITALNZ_API_KEY	digitalnz	digitalnz.org/developers
DPLA_API_KEY	dpla	pro.dp.la/developers/api-codex
EUROPEANA_API_KEY	europeana	apis.europeana.eu — test key immediate, personal ~1 week
GITHUB_TOKEN	openiti	github.com/settings/tokens — public repo read scope, optional but prevents rate limiting
NASA_ADS_API_KEY	nasaads	ui.adsabs.harvard.edu/user/settings/token
SPRINGER_OA_API_KEY + SPRINGER_META_API_KEY	springer	dev.springernature.com — same registration, two keys
ZENODO_API_KEY	zenodo	zenodo.org/account/settings/applications/tokens/new — optional, increases rate limits
SEMANTIC_SCHOLAR_API_KEY	semanticscholar	semanticscholar.org/product/api — optional, increases rate limits
TROVE_API_KEY	trove	trove.nla.gov.au/about/create-something/using-api — ~1 week approval
BASE_API_KEY	base	base-search.net/about/en/contact — requires IP whitelist

Setup

git clone https://github.com/suavecito585/alexandria-mcp
cd alexandria-mcp
npm install
npm run build

Copy .env.example to .env. Minimum configuration to run with no credentials (search and read only):

TRANSPORT=stdio

To enable library_ask:

TRANSPORT=stdio
OPENAI_API_KEY=sk-...

To enable library_ingest:

TRANSPORT=stdio
OPENAI_API_KEY=sk-...
SUPABASE_URL=https://your-project.supabase.co
SUPABASE_SERVICE_ROLE_KEY=eyJ...

Supabase Schema

Required only if using library_ingest:

create table if not exists knowledge_chunks (
  id bigserial primary key,
  content text not null,
  embedding vector(1536),
  mcp_name text,
  metadata jsonb,
  created_at timestamptz default now()
);

create table if not exists source_docs (
  id bigserial primary key,
  source_url text not null,
  mcp_name text not null,
  title text,
  source text,
  chunk_count int,
  indexed_at timestamptz,
  unique (source_url, mcp_name)
);

create index if not exists knowledge_chunks_embedding_idx
  on knowledge_chunks using ivfflat (embedding vector_cosine_ops)
  with (lists = 100);

Claude Desktop (stdio)

Minimum config (search and read only):

{
  "mcpServers": {
    "library": {
      "command": "node",
      "args": ["/path/to/alexandria-mcp/dist/index.js"],
      "env": {
        "TRANSPORT": "stdio"
      }
    }
  }
}

With library_ask and library_ingest enabled:

{
  "mcpServers": {
    "library": {
      "command": "node",
      "args": ["/path/to/alexandria-mcp/dist/index.js"],
      "env": {
        "TRANSPORT": "stdio",
        "OPENAI_API_KEY": "sk-...",
        "SUPABASE_URL": "https://your-project.supabase.co",
        "SUPABASE_SERVICE_ROLE_KEY": "eyJ..."
      }
    }
  }
}

Railway (HTTP)

Set env vars in the Railway dashboard and deploy:

railway up

Register in Claude Desktop:

{
  "mcpServers": {
    "library": {
      "url": "https://your-service.up.railway.app/mcp"
    }
  }
}

Health check: GET /health returns { status: "ok", sources: 61 }.

Adding Custom Providers

The pipeline is provider-agnostic. To add a new embedding model or vector store:

1. Implement EmbeddingProvider or VectorStoreProvider from src/types.ts
2. Add your implementation to src/pipeline/providers/
3. Register it in src/pipeline/providers/index.ts
4. Set EMBEDDING_PROVIDER or VECTOR_STORE_PROVIDER in your env

// Example: Ollama embedding provider
import type { EmbeddingProvider } from '../../types.js';

export class OllamaEmbeddingProvider implements EmbeddingProvider {
  readonly dimensions = 768;

  async embed(texts: string[]): Promise<number[][]> {
    // your implementation
  }
}