ArXivarius

A Ruby gem for fetching paper metadata from the arXiv. Retrieve titles, abstracts, authors, categories, and links for any paper on arXiv.

Installation

Add to your Gemfile:

gem 'arxivarius'

Or install directly:

gem install arxivarius

Usage

Fetching a paper

Pass any arXiv ID to Arxivarius.get:

paper = Arxivarius.get('2601.00470')

Data sources

By default the gem queries the arXiv Atom API (export.arxiv.org). That host has been unstable lately and sometimes responds with 429 Rate exceeded (Arxivarius::Error::ApiError). When it does, you can fall back to scraping the public abstract page (arxiv.org/abs/...) instead:

Arxivarius.get('2601.00470')                # arXiv API (default)
Arxivarius.get('2601.00470', source: :api)  # arXiv API, explicitly
Arxivarius.get('2601.00470', source: :web)  # scrape the abstract page

Both sources return the same Paper object, so the rest of the API below works unchanged. The web source recovers every field the API does except author affiliations, which the abstract page does not list (author.affiliations is []).

All common ID formats work:

Arxivarius.get('2601.00470')                        # current format
Arxivarius.get('2601.00470v1')                      # with version
Arxivarius.get('hep-th/9901001')                    # legacy format
Arxivarius.get('math.DG/0510097')                   # legacy with subcategory (auto-normalized)
Arxivarius.get('https://arxiv.org/abs/2601.00470')  # full URL

Paper metadata

paper.title       # => "Betelgeuse: Detection of the Expanding Wake of the Companion Star"
paper.abstract    # => "Recent analyses conclude that Betelgeuse, a red supergiant star..."
paper.comment     # => "20 pages + 1 appendix, 9 figures, accepted by ApJ"
paper.arxiv_url   # => "https://arxiv.org/abs/2601.00470v1"
paper.created_at  # => 2026-01-01 20:56:05 UTC
paper.updated_at  # => 2026-01-01 20:56:05 UTC

IDs and versions

paper.arxiv_id            # => "2601.00470"
paper.arxiv_versioned_id  # => "2601.00470v1"
paper.version             # => 1
paper.revision?           # => false (true when the paper has been updated)
paper.legacy_article?     # => false (true for pre-2007 IDs like hep-th/9901001)

PDF access

paper.available_in_pdf?  # => true
paper.pdf_url            # => "https://arxiv.org/pdf/2601.00470v1"
paper.content_types      # => ["text/html", "application/pdf"]

Links

Each paper has a list of links with URLs and content types:

paper.links.each do |link|
  link.url           # => "https://arxiv.org/pdf/2601.00470v1"
  link.content_type  # => "application/pdf"
end

Authors

paper.authors.map(&:name)
# => ["Andrea K. Dupree", "Paul I. Cristofari", "Morgan MacLeod", "Kateryna Kravchenko"]

author = paper.authors.first
author.name          # => "Andrea K. Dupree"
author.first_name    # => "Andrea K."
author.last_name     # => "Dupree"
author.affiliations  # => ["Center for Astrophysics | Harvard & Smithsonian, Cambridge, USA"]

Categories

The gem includes descriptions for all 150+ arXiv categories:

paper.categories.map(&:name)  # => ["astro-ph.SR", "physics.space-ph"]

cat = paper.primary_category
cat.name              # => "astro-ph.SR"
cat.description       # => "Solar and Stellar Astrophysics"
cat.long_description  # => "astro-ph.SR (Solar and Stellar Astrophysics)"

Error handling

begin
  paper = Arxivarius.get('2601.00470')
rescue Arxivarius::Error::PaperNotFound
  # paper does not exist on arXiv
rescue Arxivarius::Error::MalformedId
  # the ID format is invalid
end

Credits

ArXivarius is based on the outdated arxiv gem. Arxivarius picks up where it left off, with updated dependencies and a few improvements.

License

MIT