Marginalia Search website screenshot

Marginalia Search

Marginalia Search is an independent search engine focused on non-commercial content. Its API is accessible through api2.marginalia-search.com (current) and the legacy api.marginalia.nu / api.marginalia-search.com endpoints, and allows developers to perform web searches against the Marginalia index.

Marginalia Search publishes 2 APIs on the APIs.io network: Filters API and Search API. Tagged areas include Open-Source, Search, and Web Search.

Marginalia Search’s developer surface includes authentication and 5 more developer resources.

26.6/100 thin ▬ flat Agent 20/100 agent aware Full breakdown ↓
scored 2026-08-25 · rubric v0.14.0
AccessFreemiumSelf serve⚡ Free to try
2 APIs
Open-SourceSearchWeb Search

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-25 · rubric v0.14.0
Composite quality — 26.6/100 · thin
Contract Quality 13.8 / 25
Developer Ergonomics 2.4 / 20
Access Clarity 3.2 / 20
Operational Transparency 1.4 / 13
Contract Governance 0.0 / 12
Discoverability 5.9 / 10
Agent readiness — 20/100 · agent aware
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
Documented Reversibility 0 / 6
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 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 0 / 4
Delegated User Identity 0 / 6
Protected Resource Metadata 0 / 5
Registration Without a Human 0 / 6
Agentic Commerce Surface 0 / 5
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/marginalia-search: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 2

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

Marginalia Search Filters API

Manage named search filters (new API only).

Marginalia Search Search API

Search the Marginalia index.

Open Collections 4

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

API Collection

OPEN COLLECTION

Marginalia Search API

OPEN COLLECTION

Pricing Plans 1

Published pricing tiers and plan structures.

Rate Limits 1

Documented rate limits and quota policies.

Marginalia Search Rate Limits

5 limits

RATE LIMITS

FinOps 1

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

Security Posture 2

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

Marginalia Search Authentication

apiKey · 1 scheme

SECURITY

Marginalia Search Domain Security

TLSv1.3 · DNSSEC · DMARC

SECURITY

Agentic Access 1

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

Marginalia Search Agentic Access

5 operations · 2 acting

5 operations · 2 acting

AGENTIC

Resources

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

Build 1

SDKs, sample code, and the tooling you integrate with

Access & Security 2

Authentication, authorization, and security posture

Operate 1

Status, limits, changes, and where to get help

Company 1

The organization behind the API

Source (apis.yml)

apis.yml Raw ↑
aid: marginalia-search
name: Marginalia Search
description: Marginalia Search is an independent search engine focused on non-commercial content. Its API is accessible through
  api2.marginalia-search.com (current) and the legacy api.marginalia.nu / api.marginalia-search.com endpoints, and allows
  developers to perform web searches against the Marginalia index.
type: Index
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  label: Freemium · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/marginalia-search.png
tags:
- Open-Source
- Search
- Web Search
tags_raw:
- Open Source
- Search
- Web Search
url: https://raw.githubusercontent.com/api-evangelist/marginalia-search/refs/heads/main/apis.yml
created: '2025-02-06'
modified: '2026-05-19'
specificationVersion: '0.23'
apis:
- aid: marginalia-search:marginalia-search-filters-api
  name: Marginalia Search Filters API
  description: Manage named search filters (new API only).
  humanURL: https://about.marginalia-search.com/article/api/
  baseURL: https://api2.marginalia-search.com
  tags:
  - Filters
  properties:
  - type: OpenAPI
    url: openapi/marginalia-search-filters-api-openapi.yml
  - type: Documentation
    url: https://about.marginalia-search.com/article/api/
- aid: marginalia-search:marginalia-search-search-api
  name: Marginalia Search Search API
  description: Search the Marginalia index.
  humanURL: https://about.marginalia-search.com/article/api/
  baseURL: https://api2.marginalia-search.com
  tags:
  - Search
  properties:
  - type: OpenAPI
    url: openapi/marginalia-search-search-api-openapi.yml
  - type: Documentation
    url: https://about.marginalia-search.com/article/api/
common:
- type: AgenticAccess
  url: agentic-access/marginalia-search-agentic-access.yml
- type: DomainSecurity
  url: security/marginalia-search-domain-security.yml
- type: Authentication
  url: authentication/marginalia-search-authentication.yml
- type: Website
  url: https://marginalia-search.com/
- type: GitHubOrganization
  url: https://github.com/MarginaliaSearch
- type: Contact
  url: mailto:contact@marginalia-search.com
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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