Browser Skills

https://www.gutenberg.org — 78 000+ free public-domain ebooks. Every workflow here is pure http_get — no browser needed.

Do this first

Use the Gutendex REST API (gutendex.com) for all search and discovery. It is one call, returns clean JSON, and requires no auth. Go to gutenberg.org URLs only to fetch actual file content.

python

import json

# Search by title/author keyword
data = json.loads(http_get("https://gutendex.com/books/?search=pride+and+prejudice"))
# data['count'] = 6 (total matches)
# data['results'] = list of up to 32 book objects
book = data['results'][0]
# book['id'] = 1342  ← use this ID for all further calls
# book['formats']['text/plain; charset=utf-8'] = direct txt URL

# Fetch the plain-text content of that book
text = http_get(book['formats']['text/plain; charset=utf-8'])
# Returns 763 083 chars including Project Gutenberg header/footer boilerplate

For a known book ID, skip search entirely:

python

book = json.loads(http_get("https://gutendex.com/books/1342/"))

Common workflows

Search by keyword and get the first result

python

import json

data = json.loads(http_get("https://gutendex.com/books/?search=frankenstein"))
if data['results']:
    b = data['results'][0]
    print(b['id'], b['title'], b['authors'][0]['name'])
    # 84  Frankenstein; or, the modern prometheus  Shelley, Mary Wollstonecraft
    txt_url = b['formats'].get('text/plain; charset=utf-8')
    if txt_url:
        text = http_get(txt_url)

Get the most downloaded books (popularity ranking)

python

import json

data = json.loads(http_get("https://gutendex.com/books/?sort=popular"))
for b in data['results'][:10]:
    authors = ', '.join(a['name'] for a in b['authors'])
    print(f"[{b['id']}] {b['title']} — {authors} ({b['download_count']:,} downloads)")
# [84]    Frankenstein                      — Shelley, Mary Wollstonecraft  (178,271)
# [45304] The City of God, Volume I         — Augustine, of Hippo, Saint    (147,663)
# [2701]  Moby Dick; Or, The Whale          — Melville, Herman              (112,302)
# [1342]  Pride and Prejudice               — Austen, Jane                  (107,502)
# [768]   Wuthering Heights                 — Brontë, Emily                  (72,775)
# [1513]  Romeo and Juliet                  — Shakespeare, William           (70,272)
# [11]    Alice's Adventures in Wonderland  — Carroll, Lewis                 (65,243)
# [64317] The Great Gatsby                  — Fitzgerald, F. Scott           (60,632)
# [100]   Complete Works of Shakespeare     — Shakespeare, William           (60,527)
# [1260]  Jane Eyre: An Autobiography       — Brontë, Charlotte              (57,602)

Browse by genre / topic

python

import json

# 'topic' matches both subjects and bookshelves fields
data = json.loads(http_get("https://gutendex.com/books/?topic=science+fiction"))
# data['count'] = 3473 total results, 32 per page

data = json.loads(http_get("https://gutendex.com/books/?topic=detective+fiction"))
# data['count'] = 111
# data['results'][0]: id=1661 The Adventures of Sherlock Holmes — Doyle, Arthur Conan

# Filter by language (ISO 639-1 code)
data = json.loads(http_get("https://gutendex.com/books/?languages=fr&topic=roman"))
# data['count'] = 254 French books with 'roman' in topic

Paginate through results

python

import json

url = "https://gutendex.com/books/?topic=science+fiction"
books = []
while url:
    data = json.loads(http_get(url))
    books.extend(data['results'])
    url = data['next']   # None on last page
    # data['previous'] is also populated after page 1
    # e.g. data['next'] = "https://gutendex.com/books/?page=3&topic=science+fiction"
# All 3473 sci-fi books loaded across ~109 pages of 32 each

Fetch multiple specific books by ID

python

import json

data = json.loads(http_get("https://gutendex.com/books/?ids=1342,11,84"))
# Returns exactly those 3 books, count=3
for b in data['results']:
    print(b['id'], b['title'])
# 84    Frankenstein; or, the modern prometheus
# 1342  Pride and Prejudice
# 11    Alice's Adventures in Wonderland

Read the plain text of a book (boilerplate stripped)

python

raw = http_get("https://www.gutenberg.org/cache/epub/1342/pg1342.txt")
# 763 083 chars total including PG licence header and footer

START = "*** START OF THE PROJECT GUTENBERG EBOOK"
END   = "*** END OF THE PROJECT GUTENBERG EBOOK"
s = raw.find(START)
e = raw.find(END)
if s != -1:
    content = raw[raw.index('\n', s) + 1 : e].strip()
    # 743 241 chars of actual novel text

The cache URL is the most reliable direct path. The formats dict in Gutendex also provides a redirect URL that resolves to the same file:

python

# Both of these return identical content (763 083 chars):
http_get("https://www.gutenberg.org/ebooks/1342.txt.utf-8")          # redirect
http_get("https://www.gutenberg.org/cache/epub/1342/pg1342.txt")     # direct cache

Download formats available per book

Every book's formats dict maps MIME type to URL. All URLs resolve to /cache/epub/{id}/ files via redirect.

MIME type	URL pattern (after redirect)	Typical size
`text/plain; charset=utf-8`	`pg{id}.txt`	~750 KB
`text/html`	`pg{id}-images.html`	~850 KB
`application/epub+zip`	`pg{id}-images-3.epub`	~25 MB
`application/x-mobipocket-ebook`	`pg{id}-images-kf8.mobi`	~25 MB
`application/rdf+xml`	`{id}.rdf` via gutenberg.org	metadata XML
`image/jpeg`	`pg{id}.cover.medium.jpg`	cover image
`application/octet-stream`	`pg{id}-h.zip`	HTML+images zip

python

import json

b = json.loads(http_get("https://gutendex.com/books/1342/"))
# Grab every downloadable format URL:
for mime, url in b['formats'].items():
    print(mime, '->', url)
# text/html                         -> https://www.gutenberg.org/ebooks/1342.html.images
# application/epub+zip              -> https://www.gutenberg.org/ebooks/1342.epub3.images
# application/x-mobipocket-ebook   -> https://www.gutenberg.org/ebooks/1342.kf8.images
# application/rdf+xml               -> https://www.gutenberg.org/ebooks/1342.rdf
# image/jpeg                        -> https://www.gutenberg.org/cache/epub/1342/pg1342.cover.medium.jpg
# application/octet-stream          -> https://www.gutenberg.org/cache/epub/1342/pg1342-h.zip
# text/plain; charset=utf-8         -> https://www.gutenberg.org/ebooks/1342.txt.utf-8

Fetch RDF/XML metadata for a book

python

import re

rdf = http_get("https://www.gutenberg.org/cache/epub/1342/pg1342.rdf")
# Also available as: http_get("https://www.gutenberg.org/ebooks/1342.rdf")

title     = re.search(r'<dcterms:title>(.*?)</dcterms:title>', rdf, re.DOTALL)
creator   = re.findall(r'<pgterms:name>(.*?)</pgterms:name>', rdf)
birth     = re.findall(r'<pgterms:birthdate[^>]*>(\d+)', rdf)
death     = re.findall(r'<pgterms:deathdate[^>]*>(\d+)', rdf)
issued    = re.search(r'<dcterms:issued[^>]*>(.*?)</dcterms:issued>', rdf)
rights    = re.search(r'<dcterms:rights>(.*?)</dcterms:rights>', rdf)
downloads = re.search(r'<pgterms:downloads[^>]*>(\d+)</pgterms:downloads>', rdf)
language  = re.search(r'<dcterms:language>.*?<rdf:value>(.*?)</rdf:value>', rdf, re.DOTALL)
subjects  = re.findall(r'<dcterms:subject>.*?<rdf:value>(.*?)</rdf:value>.*?</dcterms:subject>', rdf, re.DOTALL)

print(title.group(1))          # Pride and Prejudice
print(creator)                 # ['Austen, Jane']
print(birth, death)            # ['1775'] ['1817']
print(issued.group(1))         # 1998-06-01
print(rights.group(1))         # Public domain in the USA.
print(int(downloads.group(1))) # 107502
print(subjects[:3])            # ['England -- Fiction', 'Young women -- Fiction', 'Love stories']

Note: <dcterms:language> value is a subject string, not a language code. For language codes use the Gutendex languages field instead.

Search the HTML catalog (25 results per page)

Use this only when you need to leverage Gutenberg's own search index (author:, title:, subject: prefix syntax).

python

import re, json

html = http_get(
    "https://www.gutenberg.org/ebooks/search/"
    "?query=shakespeare&sort_order=downloads"
)
# sort_order options: downloads, title, release_date, last_update, random

entries = re.findall(r'<li class="booklink">(.*?)</li>', html, re.DOTALL)
books = []
for e in entries:
    book_id   = re.search(r'/ebooks/(\d+)', e)
    title     = re.search(r'<span class="title">(.*?)</span>', e)
    author    = re.search(r'<span class="subtitle">(.*?)</span>', e)
    downloads = re.search(r'<span class="extra">([^<]+)</span>', e)
    books.append({
        'id':        int(book_id.group(1)) if book_id else None,
        'title':     title.group(1) if title else '',
        'author':    author.group(1) if author else '',
        'downloads': downloads.group(1).strip() if downloads else '',
    })

# books[0] = {'id': 1513, 'title': 'Romeo and Juliet',
#             'author': 'William Shakespeare', 'downloads': '74316 downloads'}

# Paginate with start_index (25 per page)
html_p2 = http_get(
    "https://www.gutenberg.org/ebooks/search/"
    "?query=shakespeare&sort_order=downloads&start_index=26"
)

Browse a bookshelf (curated genre list)

python

import re

# Bookshelf 68 = Science Fiction
html = http_get("https://www.gutenberg.org/ebooks/bookshelf/68")
titles = re.findall(r'<span class="title">(.*?)</span>', html)
# ['Twenty Thousand Leagues under the Sea', 'The War of the Worlds',
#  'The Time Machine', 'Thuvia, Maid of Mars', ...]

OPDS catalog (machine-readable Atom feed)

python

import re

feed = http_get("https://www.gutenberg.org/ebooks/search.opds/?query=dracula")
# Returns Atom XML, 7 entries per page (including 1 metadata entry)
entries = re.findall(r'<entry>(.*?)</entry>', feed, re.DOTALL)
for e in entries:
    title = re.search(r'<title>(.*?)</title>', e)
    entry_id = re.search(r'<id>(.*?)</id>', e)
    if title and entry_id and 'opds' in entry_id.group(1):
        book_id = re.search(r'/ebooks/(\d+)\.opds', entry_id.group(1))
        print(book_id.group(1), title.group(1))
# 345  Dracula

Gutendex API — full response schema

Validated against a real call to GET https://gutendex.com/books/1342/:

json

{
  "id": 1342,
  "title": "Pride and Prejudice",
  "authors": [
    {"name": "Austen, Jane", "birth_year": 1775, "death_year": 1817}
  ],
  "summaries": ["...automatically generated summary..."],
  "editors": [],
  "translators": [],
  "subjects": [
    "Courtship -- Fiction",
    "Domestic fiction",
    "England -- Fiction",
    "Love stories",
    "Sisters -- Fiction",
    "Women -- England -- Fiction",
    "Young women -- Fiction"
  ],
  "bookshelves": [
    "Best Books Ever Listings",
    "Category: British Literature",
    "Category: Classics of Literature",
    "Category: Novels",
    "Category: Romance",
    "Harvard Classics"
  ],
  "languages": ["en"],
  "copyright": false,
  "media_type": "Text",
  "formats": {
    "text/html":                       "https://www.gutenberg.org/ebooks/1342.html.images",
    "application/epub+zip":            "https://www.gutenberg.org/ebooks/1342.epub3.images",
    "application/x-mobipocket-ebook": "https://www.gutenberg.org/ebooks/1342.kf8.images",
    "application/rdf+xml":             "https://www.gutenberg.org/ebooks/1342.rdf",
    "image/jpeg":                      "https://www.gutenberg.org/cache/epub/1342/pg1342.cover.medium.jpg",
    "application/octet-stream":        "https://www.gutenberg.org/cache/epub/1342/pg1342-h.zip",
    "text/plain; charset=utf-8":       "https://www.gutenberg.org/ebooks/1342.txt.utf-8"
  },
  "download_count": 107502
}

List response wrapper (from GET /books/):

json

{
  "count": 6,
  "next": null,
  "previous": null,
  "results": [...]
}

count is the total across all pages. next / previous are fully-formed URLs ready to pass to http_get, or null when absent.

Gutendex query parameters

All parameters combine freely.

Parameter	Example	Notes
`search`	`search=moby+dick`	Matches title and author
`ids`	`ids=1342,11,84`	Comma-separated; returns only those books
`languages`	`languages=fr`	ISO 639-1 code; comma-separated for multiple
`topic`	`topic=science+fiction`	Matches subjects + bookshelves
`author_year_start`	`author_year_start=1800`	Author born on/after year
`author_year_end`	`author_year_end=1850`	Author born on/before year
`copyright`	`copyright=false`	`false`=public domain, `true`=copyrighted
`sort`	`sort=popular`	`popular` (default), `ascending`, `descending`
`page`	`page=2`	1-based; 32 results per page (not configurable)

page_size is not supported — always 32 results per page regardless.

Finding book IDs

Three ways, in order of preference:

Gutendex search — returns id directly in JSON.
Gutenberg HTML catalog — book_id = re.search(r'/ebooks/(\d+)', entry). IDs in the URL.
URL pattern — https://www.gutenberg.org/ebooks/{id} — if you already know the ID from any source.

Notable IDs validated in tests: 84 (Frankenstein), 1342 (Pride and Prejudice), 11 (Alice in Wonderland), 2701 (Moby Dick), 64317 (The Great Gatsby), 1513 (Romeo and Juliet), 100 (Complete Works of Shakespeare), 1661 (Adventures of Sherlock Holmes), 345 (Dracula).

Rate limits

Gutendex (gutendex.com) returns no X-RateLimit-* headers. Server is Apache/2.4.58 on Ubuntu. Rapid sequential calls can trigger connection resets — observed a timeout on the second call in a tight loop. Add a small delay between calls when paginating:

python

import time, json

url = "https://gutendex.com/books/?sort=popular"
while url:
    data = json.loads(http_get(url))
    # ... process data['results'] ...
    url = data['next']
    if url:
        time.sleep(0.5)   # be respectful — no published rate limit but timeouts observed

For gutenberg.org file downloads (txt, epub, etc.) there is no documented rate limit but Gutenberg asks not to use automated bulk downloading; use their offline catalogs for bulk access.

Gotchas

.opf 404: https://www.gutenberg.org/cache/epub/1342/pg1342.opf returns 404. Use .rdf instead — same path prefix, same data in RDF/XML.
formats URLs redirect: URLs like https://www.gutenberg.org/ebooks/1342.txt.utf-8 are redirect endpoints that resolve to /cache/epub/1342/pg1342.txt. Either form works with http_get (urllib follows redirects automatically), but the /cache/epub/ direct URL avoids an extra round trip.
Two text files: /files/1342/1342-0.txt (older Project Gutenberg edition, 729 KB) and /cache/epub/1342/pg1342.txt (modern edition, 763 KB) contain different versions of the same book. The Gutendex formats entry always points to the cache/modern version.
Boilerplate: Every .txt file opens with a PG licence header and closes with a footer. Strip with START/END markers (see "Read the plain text" section above).
summaries field is AI-generated: The summaries array in Gutendex responses contains automatically generated summaries, not the author's original blurb.
copyright: false means public domain in the USA. Non-US copyright status is not tracked.
page_size ignored: Passing ?page_size=5 to Gutendex has no effect — always returns 32 results.
Gutendex sort=ascending/descending sorts by ID (oldest/newest book in the catalog), not by title or author name.
Catalog search author: prefix: ?query=author:dickens searches within author names but Gutenberg's relevance ranking is fuzzy and can return unexpected results. For precise author lookup use Gutendex ?search=charles+dickens.
OPDS pagination: Only 7 entries per page (1 metadata + 6 books). Slow for bulk extraction — use Gutendex instead.
HTML catalog start_index: Pagination is 25 per page. Next page = start_index=26, then 51, 76, etc. The value appears in the rendered HTML (re.findall(r'start_index=(\d+)', html) returns the next page's value).

gutenberg

Use this skill

What the agent will read

Scraping & Data Extraction

Do this first

Common workflows

Search by keyword and get the first result

Get the most downloaded books (popularity ranking)

Browse by genre / topic

Paginate through results

Fetch multiple specific books by ID

Read the plain text of a book (boilerplate stripped)

Download formats available per book

Fetch RDF/XML metadata for a book

Search the HTML catalog (25 results per page)

Browse a bookshelf (curated genre list)

OPDS catalog (machine-readable Atom feed)

Gutendex API — full response schema

Gutendex query parameters

Finding book IDs

Rate limits

Gotchas