Library of Congress

The Library of Congress is the largest library in the world and the research arm of the US Congress. It provides REST APIs for accessing digitized collections, Congress.gov legislative data, bibliographic records, historic newspapers via Chronicling America, maps, photographs, manuscripts, and historical government documents. The loc.gov JSON API requires no authentication, while the Congress.gov API requires a free API key.

Library of Congress publishes 33 APIs on the APIs.io network, including amendments API, bill API, bound-congressional-record API, and 30 more. Tagged areas include Library, Government, Congress, Legislative Data, and Digital Collections.

The Library of Congress catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

Library of Congress’ developer surface includes authentication, documentation, engineering blog, pricing, and 13 more developer resources.

🌐 Visit website 📡 Source on GitHub

43.4/100 developing ▬ flat Agent 26/100 agent aware Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessFreeOpen⚡ Free to try

2 APIs

Library Government Congress Legislative Data Digital Collections Newspapers Maps Bibliographic RecordsHistorical Documents

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 43.4/100 · developing

Contract Quality 11.6 / 21

Developer Ergonomics 5.3 / 17

Access Clarity 10.7 / 17

Operational Transparency 0.6 / 11

Contract Governance 1.0 / 10

Discoverability 5.8 / 9

Regulatory Posture 6.4 / 15

Agent readiness — 26/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 7 / 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

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/.

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 github.com/api-evangelist/loc: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 34

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

Chronicling America API

The Chronicling America API provides access to the historic American newspapers collection digitized by the Library of Congress and its partners. Endpoints allow searching and r...

Library of Congress amendments API

Returns amendment data from the API

Library of Congress bill API

Returns bill data from the API

Library of Congress bound-congressional-record API

Returns bound Congressional Record data from the API

Library of Congress collections API

Browse and access digital collections

Library of Congress committee API

Returns committee data from the API

Library of Congress committee-meeting API

Returns committee meeting data from the API

Library of Congress committee-print API

Returns committee print data from the API

Library of Congress committee-report API

Returns committee report data from the API

Library of Congress congress API

Returns congress and congressional sessions data from the API

Library of Congress congressional-record API

Returns Congressional Record data from the API

Library of Congress crsreport API

Returns Congressional Research Service (CRS) report data from the API

Library of Congress daily-congressional-record API

Returns daily Congressional Record data from the API

Library of Congress formats API

Browse items by format type

Library of Congress hearing API

Returns hearing data from the API

Library of Congress house-communication API

Returns House communication data from the API

Library of Congress house-requirement API

Returns House requirement data from the API

Library of Congress house-vote API

[BETA] Returns House of Representatives roll call vote data from the API

Library of Congress items API

Access individual item details

Library of Congress member API

Returns member data from the API

Library of Congress nomination API

Returns nomination data from the API

Library of Congress search API

Search across all loc.gov digital collections

Library of Congress senate-communication API

Returns Senate communication data from the API

Library of Congress summaries API

Returns summaries data from the API

Library of Congress treaty API

Returns treaty data from the API

Library of Congress Bills API

The Bills API from Library of Congress — 3 operation(s) for bills.

Library of Congress Committees API

The Committees API from Library of Congress — 1 operation(s) for committees.

Library of Congress Congressional Record API

The Congressional Record API from Library of Congress — 1 operation(s) for congressional record.

Library of Congress Issues API

The Issues API from Library of Congress — 1 operation(s) for issues.

Library of Congress Laws API

The Laws API from Library of Congress — 1 operation(s) for laws.

Library of Congress Members API

The Members API from Library of Congress — 2 operation(s) for members.

Library of Congress Pages API

The Pages API from Library of Congress — 1 operation(s) for pages.

Library of Congress Resources API

The Resources API from Library of Congress — 1 operation(s) for resources.

Library of Congress Titles API

The Titles API from Library of Congress — 3 operation(s) for titles.

Scroll for all 34

Open Collections 25

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

API Collection

OPEN COLLECTION

Congress.gov amendments API

OPEN COLLECTION

Congress.gov amendments bill API

OPEN COLLECTION

Congress.gov amendments bound-congressional-record API

OPEN COLLECTION

Congress.gov amendments collections API

OPEN COLLECTION

Congress.gov amendments committee API

OPEN COLLECTION

Congress.gov amendments committee-meeting API

OPEN COLLECTION

Congress.gov amendments committee-print API

OPEN COLLECTION

Congress.gov amendments committee-report API

OPEN COLLECTION

.gov amendments congress API

OPEN COLLECTION

Congress.gov amendments congressional-record API

OPEN COLLECTION

Congress.gov amendments crsreport API

OPEN COLLECTION

Congress.gov amendments daily-congressional-record API

OPEN COLLECTION

Congress.gov amendments formats API

OPEN COLLECTION

Congress.gov amendments hearing API

OPEN COLLECTION

Congress.gov amendments house-communication API

OPEN COLLECTION

Congress.gov amendments house-requirement API

OPEN COLLECTION

Congress.gov amendments house-vote API

OPEN COLLECTION

Congress.gov amendments items API

OPEN COLLECTION

Congress.gov amendments member API

OPEN COLLECTION

Congress.gov amendments nomination API

OPEN COLLECTION

Congress.gov amendments search API

OPEN COLLECTION

Congress.gov amendments senate-communication API

OPEN COLLECTION

Congress.gov amendments summaries API

OPEN COLLECTION

Congress.gov amendments treaty API

OPEN COLLECTION

Scroll for all 25

Pricing Plans 1

Published pricing tiers and plan structures.

Loc Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Loc Rate Limits

0 limits

RATE LIMITS

FinOps 1

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

Loc Finops

FINOPS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Loc Context

11 classes · 26 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Library of Congress API Rules

6 rules · 3 warnings 3 info

SPECTRAL

JSON Schema 1

Standalone JSON Schema definitions for this provider's data models.

Congress.gov API Schemas

0 properties

JSON SCHEMA

Examples 1

Example request and response payloads for these APIs.

Loc Congress Gov Examples

6 fields

EXAMPLE

Security Posture 3

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

Loc Authentication

apiKey · 1 scheme

SECURITY

Loc Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Loc Vulnerability Disclosure

security.txt · contact published

SECURITY

Agentic Access 1

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

Loc Agentic Access

121 operations

121 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

GitHubOrg

GitHubOrg

Access & Security 3

Authentication, authorization, and security posture

VulnerabilityDisclosure

VulnerabilityDisclosure

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 3

Status, limits, changes, and where to get help

IssueTracker

IssueTracker

StatusPage

StatusPage

RateLimits

RateLimits

Commercial 3

Pricing, plans, and the legal terms of use

Pricing

Pricing

Plans

Plans

FinOps

FinOps

Company 3

The organization behind the API

Website

Website

LinkedIn

Blog

Blog

Other 2

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Source (apis.yml)

aid: loc
name: Library of Congress
description: The Library of Congress is the largest library in the world and the research arm of the US Congress. It provides
  REST APIs for accessing digitized collections, Congress.gov legislative data, bibliographic records, historic newspapers
  via Chronicling America, maps, photographs, manuscripts, and historical government documents. The loc.gov JSON API requires
  no authentication, while the Congress.gov API requires a free API key.
deliveryModel:
  model: unknown
  open_source: unknown
  commercial: true
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  - pricing
  - repository-unlicensed
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: free
  onboarding: open
  trial: false
  try_now: true
  public: true
  label: Free · Open access
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/loc.png
url: https://raw.githubusercontent.com/api-evangelist/loc/refs/heads/main/apis.yml
created: '2026-06-13'
modified: '2026-06-13'
specificationVersion: '0.23'
type: Index
tags:
- Library
- Government
- Congress
- Legislative Data
- Digital Collections
- Newspapers
- Maps
- Bibliographic Records
- Historical Documents
apis:
- name: Chronicling America API
  description: The Chronicling America API provides access to the historic American newspapers collection digitized by the
    Library of Congress and its partners. Endpoints allow searching and retrieving pages, titles, batches, and OCR text. No
    authentication is required.
  image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
  humanURL: https://chroniclingamerica.loc.gov/about/api/
  baseURL: https://chroniclingamerica.loc.gov
  tags:
  - Newspapers
  - Historical
  - Digitized
  - Search
  - OCR
  properties:
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  contact:
  - FN: Library of Congress
    url: https://www.loc.gov/about/contact-us/
- aid: loc:loc-amendments-api
  name: Library of Congress amendments API
  description: Returns amendment data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Amendments
  tags_raw:
  - amendments
  properties:
  - type: OpenAPI
    url: openapi/loc-amendments-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-bill-api
  name: Library of Congress bill API
  description: Returns bill data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Bill
  tags_raw:
  - bill
  properties:
  - type: OpenAPI
    url: openapi/loc-bill-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-bound-congressional-record-api
  name: Library of Congress bound-congressional-record API
  description: Returns bound Congressional Record data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - bound-congressional-record
  properties:
  - type: OpenAPI
    url: openapi/loc-bound-congressional-record-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-collections-api
  name: Library of Congress collections API
  description: Browse and access digital collections
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Collection
  tags_raw:
  - collections
  properties:
  - type: OpenAPI
    url: openapi/loc-collections-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-committee-api
  name: Library of Congress committee API
  description: Returns committee data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - committee
  properties:
  - type: OpenAPI
    url: openapi/loc-committee-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-committee-meeting-api
  name: Library of Congress committee-meeting API
  description: Returns committee meeting data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - committee-meeting
  properties:
  - type: OpenAPI
    url: openapi/loc-committee-meeting-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-committee-print-api
  name: Library of Congress committee-print API
  description: Returns committee print data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - committee-print
  properties:
  - type: OpenAPI
    url: openapi/loc-committee-print-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-committee-report-api
  name: Library of Congress committee-report API
  description: Returns committee report data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - committee-report
  properties:
  - type: OpenAPI
    url: openapi/loc-committee-report-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-congress-api
  name: Library of Congress congress API
  description: Returns congress and congressional sessions data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Congress
  tags_raw:
  - congress
  properties:
  - type: OpenAPI
    url: openapi/loc-congress-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-congressional-record-api
  name: Library of Congress congressional-record API
  description: Returns Congressional Record data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Congressional Record
  tags_raw:
  - congressional-record
  properties:
  - type: OpenAPI
    url: openapi/loc-congressional-record-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-crsreport-api
  name: Library of Congress crsreport API
  description: Returns Congressional Research Service (CRS) report data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - crsreport
  properties:
  - type: OpenAPI
    url: openapi/loc-crsreport-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-daily-congressional-record-api
  name: Library of Congress daily-congressional-record API
  description: Returns daily Congressional Record data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - daily-congressional-record
  properties:
  - type: OpenAPI
    url: openapi/loc-daily-congressional-record-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-formats-api
  name: Library of Congress formats API
  description: Browse items by format type
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Formats
  tags_raw:
  - formats
  properties:
  - type: OpenAPI
    url: openapi/loc-formats-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-hearing-api
  name: Library of Congress hearing API
  description: Returns hearing data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Hearing
  tags_raw:
  - hearing
  properties:
  - type: OpenAPI
    url: openapi/loc-hearing-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-house-communication-api
  name: Library of Congress house-communication API
  description: Returns House communication data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - house-communication
  properties:
  - type: OpenAPI
    url: openapi/loc-house-communication-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-house-requirement-api
  name: Library of Congress house-requirement API
  description: Returns House requirement data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - house-requirement
  properties:
  - type: OpenAPI
    url: openapi/loc-house-requirement-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-house-vote-api
  name: Library of Congress house-vote API
  description: '[BETA] Returns House of Representatives roll call vote data from the API'
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - house-vote
  properties:
  - type: OpenAPI
    url: openapi/loc-house-vote-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-items-api
  name: Library of Congress items API
  description: Access individual item details
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Item
  tags_raw:
  - items
  properties:
  - type: OpenAPI
    url: openapi/loc-items-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-member-api
  name: Library of Congress member API
  description: Returns member data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Member
  tags_raw:
  - member
  properties:
  - type: OpenAPI
    url: openapi/loc-member-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-nomination-api
  name: Library of Congress nomination API
  description: Returns nomination data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - nomination
  properties:
  - type: OpenAPI
    url: openapi/loc-nomination-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-search-api
  name: Library of Congress search API
  description: Search across all loc.gov digital collections
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Search
  tags_raw:
  - search
  properties:
  - type: OpenAPI
    url: openapi/loc-search-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-senate-communication-api
  name: Library of Congress senate-communication API
  description: Returns Senate communication data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - senate-communication
  properties:
  - type: OpenAPI
    url: openapi/loc-senate-communication-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-summaries-api
  name: Library of Congress summaries API
  description: Returns summaries data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Summary
  tags_raw:
  - summaries
  properties:
  - type: OpenAPI
    url: openapi/loc-summaries-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:loc-treaty-api
  name: Library of Congress treaty API
  description: Returns treaty data from the API
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - treaty
  properties:
  - type: OpenAPI
    url: openapi/loc-treaty-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Documentation
    url: https://api.congress.gov/
  - type: GitHubRepository
    url: https://github.com/LibraryOfCongress/api.congress.gov
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-bills-api
  name: Library of Congress Bills API
  description: The Bills API from Library of Congress — 3 operation(s) for bills.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Bills
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-bills-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-committees-api
  name: Library of Congress Committees API
  description: The Committees API from Library of Congress — 1 operation(s) for committees.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Committees
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-committees-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-congressional-record-api
  name: Library of Congress Congressional Record API
  description: The Congressional Record API from Library of Congress — 1 operation(s) for congressional record.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Congressional Record
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-congressional-record-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-issues-api
  name: Library of Congress Issues API
  description: The Issues API from Library of Congress — 1 operation(s) for issues.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Issues
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-issues-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-laws-api
  name: Library of Congress Laws API
  description: The Laws API from Library of Congress — 1 operation(s) for laws.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Laws
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-laws-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-members-api
  name: Library of Congress Members API
  description: The Members API from Library of Congress — 2 operation(s) for members.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Members
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-members-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-pages-api
  name: Library of Congress Pages API
  description: The Pages API from Library of Congress — 1 operation(s) for pages.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Pages
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-pages-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-resources-api
  name: Library of Congress Resources API
  description: The Resources API from Library of Congress — 1 operation(s) for resources.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Resources
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-resources-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
- aid: loc:library-of-congress-titles-api
  name: Library of Congress Titles API
  description: The Titles API from Library of Congress — 3 operation(s) for titles.
  humanURL: https://www.loc.gov/apis/json-and-yaml/
  baseURL: https://www.loc.gov
  tags:
  - Titles
  properties:
  - type: OpenAPI
    url: openapi/library-of-congress-titles-api-openapi.yml
  - type: Documentation
    url: https://www.loc.gov/apis/json-and-yaml/
  - type: Reference
    url: https://www.loc.gov/apis/json-and-yaml/requests/
  - type: Documentation
    url: https://chroniclingamerica.loc.gov/about/api/
  - type: Documentation
    url: https://github.com/LibraryOfCongress/api.congress.gov/
  - type: Signup
    url: https://api.congress.gov/sign-up/
common:
- type: CapabilityMap
  url: capabilities/loc-capability-edges.yml
  name: Library of Congress Business Capability Map
- type: IssueTracker
  url: https://github.com/LibraryOfCongress/api.congress.gov/issues
- type: AgenticAccess
  url: agentic-access/loc-agentic-access.yml
- type: VulnerabilityDisclosure
  url: security/loc-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/loc-domain-security.yml
- type: Authentication
  url: authentication/loc-authentication.yml
- type: Website
  url: https://www.loc.gov
- type: Documentation
  url: https://www.loc.gov/apis/
- type: GitHubOrg
  url: https://github.com/LibraryOfCongress
- type: LinkedIn
  url: https://www.linkedin.com/company/library-of-congress
- type: Blog
  url: https://blogs.loc.gov/thesignal/
- type: Pricing
  url: https://www.loc.gov/apis/
- type: StatusPage
  url: https://uptime.com/upstatus/loc.gov
- type: X
  url: https://twitter.com/librarycongress
- type: Plans
  url: plans/loc-plans-pricing.yml
- type: RateLimits
  url: rate-limits/loc-rate-limits.yml
- type: FinOps
  url: finops/loc-finops.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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