Open Library

Open Library offers a suite of APIs to help developers get up and running with its data. This includes RESTful APIs that make Open Library data available in JSON, YAML, and RDF/XML formats, plus a Search Inside full-text search service, cover image endpoints, and read-protocol library lookup APIs. Most resources also expose machine-readable representations by appending .json, .yml, or .rdf to any Open Library URL.

Open Library publishes 13 API contracts indexed on the APIs.io network, including Authors API, Editions API, Lists API, and 10 more. Tagged areas include Authors, Books, Catalog, Covers, and Library.

The Open Library catalog on APIs.io includes 1 Spectral governance ruleset.

Open Library’s developer surface includes documentation, engineering blog, and 11 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

23.9/100 emerging ▬ flat Agent 20/100 agent aware Front door AI 1/6 silent Heartbeat 97/100 alive saas Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessFreemium

1 published contract

Authors Books CatalogCoversLibrary Open Data Reading Lists Search Subjects

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Educational Content & Learning Resource Management

BC-4790

Lists

GET /lists/{listId}.json

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 23.9/100 · emerging

Contract Quality 8.8 / 21

Developer Ergonomics 2.0 / 17

Access Clarity 3.1 / 17

Operational Transparency 1.2 / 11

Contract Governance 1.4 / 10

Discoverability 4.9 / 9

Regulatory Posture 1.5 / 15

Agent readiness — 20/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 9 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 4 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Education & Research regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics does not apply to this provider. The published contracts declare no write operations, and a read-only API cannot create-or-update. The facet is excluded from this provider's denominator entirely — not scored zero. A reference or data API is not deficient for being unable to upsert.

The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Machine-Readable Auth +10 pts — a served openid-configuration/oauth-authorization-server carrying `issuer` (served), else the securitySchemes class in the provider OpenAPIs — bound (mutualTLS, DPoP, Signature) > negotiable (oauth2 authorizationCode/clientCredentials, openIdConnect) > bearer (http bearer, apiKey)
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Request/Response Examples +7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document

7 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Developer Ergonomics scores 11.9 — up to +17.6 composite points
Access Clarity scores 18.4 — up to +16.3 composite points
Contract Quality scores 41.5 — up to +14.6 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/open-library/apis.yml: open an issue on github.com/api-evangelist/open-library to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Markets this provider is in provisional

The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.

Market	Position	Depth	Registered MCP server	Declares compatibility
Obsidian Community Plugins (third-party APIs the Obsidian plugin ecosystem integrates)	long-tail	5.0 (thin)	-	-

Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.

Standards implemented 1

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

OpenAPI

measured — observed by APIs.io (published)

APIs 13

Individual APIs this provider publishes, each with its own machine-readable definition.

Open Library Search Inside API

Full-text search across the millions of digitized books in the Internet Archive's collection, returning matching passages and book identifiers.

Open Library Covers API

Retrieve book and author cover images by Open Library ID, ISBN, OCLC, LCCN, or Goodreads ID, in small, medium, and large sizes.

Open Library My Books API

Access a patron's public reading log: Want to Read, Currently Reading, and Already Read shelves for a given Open Library account.

Open Library Recent Changes API

Stream recent edits across the Open Library catalog including works, editions, authors, lists, and subjects, with filtering by kind and time range.

Open Library Read API

Legacy partner API that returns availability and read URLs for books matched by ISBN, OCLC, LCCN, or OLID identifiers across libraries and the Internet Archive.

Open Library Authors API

Fetch author records and their works by Open Library Author ID. Supports JSON, YAML, and RDF/XML representations.

Open Library Editions API

Retrieve edition-level records (specific printings, ISBNs, formats) by Open Library Edition ID, ISBN-10, ISBN-13, OCLC, or LCCN.

Open Library Lists API

Read and manage user-curated reading lists. Authenticated patrons can create lists and add or remove works, editions, and subjects.

Open Library Recentchanges.json API

The Recentchanges.json API from Open Library — 1 operation(s) for recentchanges.json.

Open Library Search API

Search Open Library's catalog of books, authors, lists, and subjects. Returns JSON results for full-text and faceted queries, with options for pagination, field selection, and l...

Open Library Search.json API

The Search.json API from Open Library — 1 operation(s) for search.json.

Open Library Subjects API

Retrieve books, works, and metadata grouped by subject (genre, topic, place, time, person) with paging and faceting.

Open Library Works API

Retrieve work-level records (the abstract concept of a book independent of edition) by Open Library Work ID. Returns JSON, YAML, or RDF/XML.

Scroll for all 13

Open Collections 9

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Open Library Authors API

OPEN COLLECTION

Open Library Authors Editions API

OPEN COLLECTION

Open Library Authors Lists API

OPEN COLLECTION

Open Library Authors Recentchanges.json API

OPEN COLLECTION

Open Library Authors Search API

OPEN COLLECTION

Open Library Authors Search.json API

OPEN COLLECTION

Open Library Authors Subjects API

OPEN COLLECTION

Open Library Authors Works API

OPEN COLLECTION

Open Library API

OPEN COLLECTION

Scroll for all 9

Open Library API pricing

Not yet checked against Open Library's own pricing page. Compiled by API Evangelist on 2026-05-04; confirm before you rely on a figure. A free plan or tier is listed.

Plan	Price
Free freemium	Free
Professional paid	Free
Enterprise enterprise	—

Plan details, limits and sources →

Rate limits

Free Tier Default: 10 requests per minute
Free Tier Monthly Quota: 1000 requests per month
Professional Tier Default: 100 requests per minute

Compiled by API Evangelist, not yet checked against Open Library's documentation. All 5 limits →

Pricing Plans 1

Published pricing tiers and plan structures.

Open Library Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Open Library Rate Limits

5 limits

RATE LIMITS

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

Open Library

SLA

FinOps 1

Cost, billing, and metering signals for API financial operations.

Open Library Finops

FINOPS

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Open Library API Rules

35 rules · 33 errors 1 warnings 1 info

SPECTRAL

Security Posture 1

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Open Library Domain Security

TLSv1.3

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Open Library Agentic Access

9 operations

9 operations · 0 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Operate 2

Status, limits, changes, and where to get help

RateLimits

RateLimits

Issues

Issues

Commercial 3

Pricing, plans, and the legal terms of use

Plans

Plans

FinOps

FinOps

TermsOfService

TermsOfService

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 2

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Bulk Data Dumps

Bulk Data Dumps

Source (apis.yml)

aid: open-library
name: Open Library
description: Open Library offers a suite of APIs to help developers get up and running with its data. This includes RESTful
  APIs that make Open Library data available in JSON, YAML, and RDF/XML formats, plus a Search Inside full-text search service,
  cover image endpoints, and read-protocol library lookup APIs. Most resources also expose machine-readable representations
  by appending .json, .yml, or .rdf to any Open Library URL.
type: Index
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: low
  source:
  - plans
  - security
  generated: '2026-11-06'
  method: derived
position: Consuming
access: 3rd-Party
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/open-library.png
tags:
- Authors
- Books
- Catalog
- Covers
- Library
- Open Data
- Reading Lists
- Search
- Subjects
tags_raw:
- Authors
- Books
- Catalog
- Covers
- Libraries
- Open Data
- Reading Lists
- Search
- Subjects
created: '2025-02-06'
modified: '2026-04-28'
url: https://raw.githubusercontent.com/api-evangelist/open-library/refs/heads/main/apis.yml
specificationVersion: '0.23'
apis:
- aid: open-library:open-library-search-inside-api
  name: Open Library Search Inside API
  description: Full-text search across the millions of digitized books in the Internet Archive's collection, returning matching
    passages and book identifiers.
  humanURL: https://openlibrary.org/dev/docs/api/search_inside
  tags:
  - Books
  - Full Text
  - Search
  properties:
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/search_inside
- aid: open-library:open-library-covers-api
  name: Open Library Covers API
  description: Retrieve book and author cover images by Open Library ID, ISBN, OCLC, LCCN, or Goodreads ID, in small, medium,
    and large sizes.
  humanURL: https://openlibrary.org/dev/docs/api/covers
  tags:
  - Covers
  - Image
  - Media
  tags_raw:
  - Covers
  - Images
  - Media
  properties:
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/covers
- aid: open-library:open-library-mybooks-api
  name: Open Library My Books API
  description: 'Access a patron''s public reading log: Want to Read, Currently Reading, and Already Read shelves for a given
    Open Library account.'
  humanURL: https://openlibrary.org/dev/docs/api/mybooks
  tags:
  - Reading Log
  - User Data
  properties:
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/mybooks
- aid: open-library:open-library-recent-changes-api
  name: Open Library Recent Changes API
  description: Stream recent edits across the Open Library catalog including works, editions, authors, lists, and subjects,
    with filtering by kind and time range.
  humanURL: https://openlibrary.org/dev/docs/api/recentchanges
  tags:
  - Activity
  - Changes
  - Feed
  properties:
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/recentchanges
- aid: open-library:open-library-read-api
  name: Open Library Read API
  description: Legacy partner API that returns availability and read URLs for books matched by ISBN, OCLC, LCCN, or OLID identifiers
    across libraries and the Internet Archive.
  humanURL: https://openlibrary.org/dev/docs/api/read
  tags:
  - Availability
  - Library
  - Lookup
  tags_raw:
  - Availability
  - Libraries
  - Lookup
  properties:
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/read
- aid: open-library:open-library-authors-api
  name: Open Library Authors API
  description: Fetch author records and their works by Open Library Author ID. Supports JSON, YAML, and RDF/XML representations.
  humanURL: https://openlibrary.org/dev/docs/api/authors
  tags:
  - Authors
  - Catalog
  properties:
  - type: OpenAPI
    url: openapi/open-library-authors-api-openapi.yml
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/authors
- aid: open-library:open-library-editions-api
  name: Open Library Editions API
  description: Retrieve edition-level records (specific printings, ISBNs, formats) by Open Library Edition ID, ISBN-10, ISBN-13,
    OCLC, or LCCN.
  humanURL: https://openlibrary.org/dev/docs/api/books
  tags:
  - Editions
  - Books
  - Catalog
  - ISBN
  properties:
  - type: OpenAPI
    url: openapi/open-library-editions-api-openapi.yml
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/books
- aid: open-library:open-library-lists-api
  name: Open Library Lists API
  description: Read and manage user-curated reading lists. Authenticated patrons can create lists and add or remove works,
    editions, and subjects.
  humanURL: https://openlibrary.org/dev/docs/api/lists
  tags:
  - List
  - Reading Lists
  - User Data
  tags_raw:
  - Lists
  - Reading Lists
  - User Data
  properties:
  - type: OpenAPI
    url: openapi/open-library-lists-api-openapi.yml
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/lists
- aid: open-library:open-library-recentchanges-json-api
  name: Open Library Recentchanges.json API
  description: The Recentchanges.json API from Open Library — 1 operation(s) for recentchanges.json.
  humanURL: https://openlibrary.org/dev/docs/api/search
  tags:
  - Recentchanges.json
  properties:
  - type: OpenAPI
    url: openapi/open-library-recentchanges-json-api-openapi.yml
- aid: open-library:open-library-search-api
  name: Open Library Search API
  description: Search Open Library's catalog of books, authors, lists, and subjects. Returns JSON results for full-text and
    faceted queries, with options for pagination, field selection, and language filtering.
  humanURL: https://openlibrary.org/dev/docs/api/search
  tags:
  - Search
  - Books
  - Catalog
  properties:
  - type: OpenAPI
    url: openapi/open-library-search-api-openapi.yml
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/search
- aid: open-library:open-library-search-json-api
  name: Open Library Search.json API
  description: The Search.json API from Open Library — 1 operation(s) for search.json.
  humanURL: https://openlibrary.org/dev/docs/api/search
  tags:
  - Search.json
  properties:
  - type: OpenAPI
    url: openapi/open-library-search-json-api-openapi.yml
- aid: open-library:open-library-subjects-api
  name: Open Library Subjects API
  description: Retrieve books, works, and metadata grouped by subject (genre, topic, place, time, person) with paging and
    faceting.
  humanURL: https://openlibrary.org/dev/docs/api/subjects
  tags:
  - Subjects
  - Catalog
  - Taxonomy
  properties:
  - type: OpenAPI
    url: openapi/open-library-subjects-api-openapi.yml
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/subjects
- aid: open-library:open-library-works-api
  name: Open Library Works API
  description: Retrieve work-level records (the abstract concept of a book independent of edition) by Open Library Work ID.
    Returns JSON, YAML, or RDF/XML.
  humanURL: https://openlibrary.org/dev/docs/api/books
  tags:
  - Works
  - Books
  - Catalog
  properties:
  - type: OpenAPI
    url: openapi/open-library-works-api-openapi.yml
  - type: Documentation
    url: https://openlibrary.org/dev/docs/api/books
common:
- type: Plans
  url: plans/open-library-plans-pricing.yml
- type: RateLimits
  url: rate-limits/open-library-rate-limits.yml
- type: FinOps
  url: finops/open-library-finops.yml
- type: CapabilityMap
  url: capabilities/open-library-capability-edges.yml
  name: Open Library Business Capability Map
- type: AgenticAccess
  url: agentic-access/open-library-agentic-access.yml
- type: DomainSecurity
  url: security/open-library-domain-security.yml
- type: Website
  url: https://openlibrary.org/
- type: Documentation
  url: https://openlibrary.org/developers/api
- type: Bulk Data Dumps
  url: https://openlibrary.org/developers/dumps
- type: GitHubOrganization
  url: https://github.com/internetarchive/openlibrary
- type: Issues
  url: https://github.com/internetarchive/openlibrary/issues
- type: Blog
  url: https://blog.openlibrary.org/
- type: TermsOfService
  url: https://archive.org/about/terms.php
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

Open Library API — frequently asked questions

Does Open Library have an API?

Yes. APIs.io lists 13 APIs from Open Library, including Open Library Search Inside API, Open Library Covers API and Open Library My Books API, and 10 more.

Is there an OpenAPI specification for the Open Library API?

Yes. APIs.io indexes 8 OpenAPI specifications for Open Library, each linked for download from this page.

How much does the Open Library API cost?

APIs.io lists 3 pricing plans for Open Library, with each plan's price, limits and inclusions under Pricing on this page.

Is the Open Library API ready for AI agents?

Open Library has a Kin Score of 23.9 out of 100 (emerging) and an Agent Readiness score of 19.8 (agent-aware), scored by API Evangelist on 2026-11-06.

Work with this as data

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Tools for providers

9 MCP tools reach this

find_providersBrowse and filter every provider in the catalog.
get_provider_artifactsEvery artifact this provider publishes, grouped by type.
get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
get_provider_ratingPRO — composite, band, trend and facet scores.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

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