Fatcat
Fatcat is a versioned, user-editable open catalog of published research works maintained by the Internet Archive. It tracks bibliographic metadata, links papers to full-text copies, and preserves access to scholarly publications including journal articles, conference proceedings, and datasets across millions of research works.
Limited machine-readable signal and partial portal coverage — documentation a human can read, but little a machine or agent can consume without scraping.
API Evangelist profiles Fatcat the way a machine reads it — 28 machine-readable artifacts across 11 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.
Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Fatcat scores 41.4/100 (thin), with a separate agent-readiness read of 48/100 (agent ready). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.
Kin Score
This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.
Kin Score
How this is scored →scored 2026-07-27 · rubric v0.5
How we profile Fatcat
Each block below is one kind of artifact we hold for Fatcat. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.
APIs 11
Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.
Individual APIs this provider publishes, each with its own machine-readable definition.
Fatcat auth API
Helper methods and internal APIs for editor authentication. # TAGLINE
Fatcat changelog API
The **Changelog** is the ordered feed of editgroups which have been # TAGLINE accepted into the catalog. # TAGLINE
Fatcat containers API
**Container** entities represent publication venues like journals, # TAGLINE conference proceedings, book series, or blogs. They group publications # TAGLINE ("releases"). # TAG...
Fatcat creators API
**Creator** entities represent individuals (or organizations, or other # TAGLINE agents) who contribute to the creation of specific releases # TAGLINE (publications). # TAGLINE ...
Fatcat editgroups API
**Editgroups** are sets of changes, each to individual entities in the # TAGLINE catalog. Every edit must be part of an editgroup which is reviewed and # TAGLINE accepted (merge...
Fatcat editors API
**Editors** are human user accounts and bots that make changes to the # TAGLINE Fatcat catalog. # TAGLINE The API allows fetching (and updating) metadata about individual editor...
Fatcat files API
**File** entities represent unique digital files which are full # TAGLINE manifestations of specific releases (publications), such as fulltext PDF # TAGLINE files, JATS XML docu...
Fatcat filesets API
**Fileset** entities represent sets of digital files, as well as locations # TAGLINE where they can be found on the public web. Filesets most commonly # TAGLINE represent datase...
Fatcat releases API
**Release** entities represent specific published versions of a research # TAGLINE work, such as a pre-print, a journal article, a book (or chapter), or a # TAGLINE scholarly bl...
Fatcat webcaptures API
**Web Capture** entities represent archival snapshots of web pages (or # TAGLINE other web resources), which are usually complete manifestations of a # TAGLINE specific release ...
Fatcat works API
**Work** entities group several Release entities which are different # TAGLINE versions of the same abstract piece of research. For example, three # TAGLINE release entities rep...
Scroll within the panel for all 11 ·
Pricing Plans 1
Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the six things the Kin Score reads for commercial clarity.
Published pricing tiers and plan structures.
Plans
PLANSRate Limits 1
Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.
Documented rate limits and quota policies.
Rate Limits
RATE LIMITSFinOps 1
Cost, billing, and metering signals let a buyer model the financial operations of an API before it's live. We profile them for the same reason we profile pricing: the money is part of the contract.
Cost, billing, and metering signals for API financial operations.
Finops
FINOPSSemantic Vocabularies 1
JSON-LD contexts give the data shared meaning across APIs. We profile them because semantics are what let a machine reconcile 'customer' here with 'customer' somewhere else.
JSON-LD contexts and semantic vocabularies used across these APIs.
context Context
JSON-LDSpectral Rules 1
Governance rulesets we run against this provider's specs — the automated checks behind parts of the score. Profiling them makes the quality bar explicit and re-runnable, not a matter of opinion.
Fatcat API Rules
SPECTRALJSON Schema 5
Standalone JSON Schema definitions describe the data models behind the API. We profile them so the shapes are validatable on their own — useful long after a single request is forgotten.
Standalone JSON Schema definitions for this provider's data models.
ContainerEntity
JSON SCHEMACreatorEntity
JSON SCHEMAEditgroup
JSON SCHEMAFileEntity
JSON SCHEMAReleaseEntity
JSON SCHEMAExamples 5
Real request and response payloads are what turn a spec from abstract into obvious — and they're one of the twelve things an agent needs to call an API correctly on the first try.
Example request and response payloads for these APIs.
Container Entity Example
EXAMPLECreator Entity Example
EXAMPLEEditgroup Example
EXAMPLEFile Entity Example
EXAMPLERelease Entity Example
EXAMPLESecurity Posture 1
Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.
Recommended x-agentic-access execution contracts for AI agents.
Resources
Every other property we hold for Fatcat — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.
Agent Surfaces 1
MCP servers, agent skills, and machine-readable catalogs
Access & Security 1
Authentication, authorization, and security posture
← All providers · Data indexed from github.com/api-evangelist/fatcat · machine-readable index on apis.io