Retrofit website screenshot

Retrofit

Retrofit is a type-safe HTTP client for Android and the JVM (Java and Kotlin) built by Square, turning HTTP API interfaces into callable Java objects with annotation-based configuration and pluggable serialization. Retrofit is built on top of OkHttp and supports synchronous/asynchronous execution, JSON/XML/Protobuf converters, RxJava adapters, and Kotlin coroutines. Current stable version is 3.0.0.

Retrofit publishes 4 APIs on the APIs.io network. Tagged areas include Android, HTTP Client, Java, Kotlin, and Library.

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

Retrofit’s developer surface includes documentation, GitHub presence, changelog, and 7 more developer resources.

🌐 Visit website 📡 Source on GitHub
18.0/100 emerging ▬ flat Agent 3/100 human only Full breakdown ↓
scored 2026-09-14 · rubric v0.22.0
AccessFreemium
4 APIs
AndroidHTTP ClientJavaKotlinLibraryMobileOpen-SourceSDKSquare

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-09-14 · rubric v0.22.0
Composite quality — 18.0/100 · emerging
Contract Quality 4.0 / 21
Developer Ergonomics 0.0 / 17
Access Clarity 2.7 / 17
Operational Transparency 2.9 / 11
Contract Governance 2.6 / 10
Discoverability 5.5 / 9
Regulatory Posture 1.4 / 15
Agent readiness — 3/100 · human only
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 10
Documented Reversibility 0 / 6
MCP Server 0 / 12
Machine-Readable Auth 0 / 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 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 could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.
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/retrofit: 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 4

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

Retrofit

Retrofit is a type-safe HTTP client for the JVM that turns annotated Java/Kotlin interfaces into HTTP API calls. Supports all HTTP methods via annotations. Built on OkHttp with ...

Retrofit Converters

Pluggable serialization converters for Retrofit supporting Gson, Moshi, Jackson, Kotlinx Serialization, JAXB, Protocol Buffers (Wire), SimpleXML, and Scalars.

Retrofit Call Adapters

Pluggable call adapters that allow Retrofit interfaces to return RxJava Observables (v1, v2, v3), Java 8 CompletableFuture, Guava ListenableFuture, and Scala Future types.

Retrofit Mock

Provides behavior-simulating implementations of Retrofit interfaces for local testing without requiring a network connection.

Pricing Plans 1

Published pricing tiers and plan structures.

Retrofit Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Retrofit Rate Limits

5 limits

RATE LIMITS

FinOps 1

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

Retrofit Finops

FINOPS

Semantic Vocabularies 1

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

Retrofit Context

11 classes · 4 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Retrofit API Rules

5 rules · 3 warnings 2 info

SPECTRAL

JSON Schema 1

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

Retrofit Library

10 properties

JSON SCHEMA

JSON Structure 1

JSON Structure definitions describing this provider's data shapes.

Retrofit Library Structure

0 properties

JSON STRUCTURE

Resources

Documentation 1

Reference material describing how the API behaves

Documentation
Documentation

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

Vocabulary
Vocabulary

Build 2

SDKs, sample code, and the tooling you integrate with

GitHub
GitHub
 GitHubOrganization
GitHubOrganization

Operate 2

Status, limits, changes, and where to get help

ChangeLog
ChangeLog
 Issues
Issues

Commercial 1

Pricing, plans, and the legal terms of use

License
License

Company 1

The organization behind the API

Website
Website

Other 2

Properties that don't map to a standard resource type

Maven
Maven
 JavaDoc
JavaDoc

Source (apis.yml)

apis.yml Raw ↑ 
aid: retrofit
name: Retrofit
description: Retrofit is a type-safe HTTP client for Android and the JVM (Java and Kotlin) built by Square, turning HTTP API
  interfaces into callable Java objects with annotation-based configuration and pluggable serialization. Retrofit is built
  on top of OkHttp and supports synchronous/asynchronous execution, JSON/XML/Protobuf converters, RxJava adapters, and Kotlin
  coroutines. Current stable version is 3.0.0.
type: Index
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - none
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/retrofit.png
tags:
- Android
- HTTP Client
- Java
- Kotlin
- Library
- Mobile
- Open-Source
- SDK
- Square
tags_raw:
- Android
- HTTP Client
- Java
- Kotlin
- Library
- Mobile
- Open Source
- SDK
- Square
url: https://raw.githubusercontent.com/api-evangelist/retrofit/refs/heads/main/apis.yml
created: '2026-03-27'
modified: '2026-05-02'
specificationVersion: '0.23'
apis:
- aid: retrofit:retrofit-core
  name: Retrofit
  description: Retrofit is a type-safe HTTP client for the JVM that turns annotated Java/Kotlin interfaces into HTTP API calls.
    Supports all HTTP methods via annotations. Built on OkHttp with support for synchronous Call, RxJava, Java 8 CompletableFuture,
    and Kotlin coroutines.
  humanURL: https://square.github.io/retrofit/
  tags:
  - Android
  - HTTP Client
  - Java
  - Kotlin
  - Open-Source
  tags_raw:
  - Android
  - HTTP Client
  - Java
  - Kotlin
  - Open Source
  properties:
  - type: Documentation
    url: https://square.github.io/retrofit/
  - type: GitHub
    url: https://github.com/square/retrofit
  - type: ChangeLog
    url: https://github.com/square/retrofit/blob/trunk/CHANGELOG.md
  - type: JavaDoc
    url: https://square.github.io/retrofit/2.x/retrofit/
  - type: JSONSchema
    url: https://raw.githubusercontent.com/api-evangelist/retrofit/refs/heads/main/json-schema/retrofit-library-schema.json
- aid: retrofit:retrofit-converters
  name: Retrofit Converters
  description: Pluggable serialization converters for Retrofit supporting Gson, Moshi, Jackson, Kotlinx Serialization, JAXB,
    Protocol Buffers (Wire), SimpleXML, and Scalars.
  humanURL: https://square.github.io/retrofit/#converters
  tags:
  - Converters
  - Gson
  - Jackson
  - Moshi
  - Protobuf
  - Serialization
  properties:
  - type: Documentation
    url: https://square.github.io/retrofit/#converters
  - type: GitHub
    url: https://github.com/square/retrofit/tree/trunk/retrofit-converters
- aid: retrofit:retrofit-adapters
  name: Retrofit Call Adapters
  description: Pluggable call adapters that allow Retrofit interfaces to return RxJava Observables (v1, v2, v3), Java 8 CompletableFuture,
    Guava ListenableFuture, and Scala Future types.
  humanURL: https://square.github.io/retrofit/#call-adapters
  tags:
  - Adapters
  - Async
  - Java 8
  - RxJava
  - Scala
  properties:
  - type: Documentation
    url: https://square.github.io/retrofit/#call-adapters
  - type: GitHub
    url: https://github.com/square/retrofit/tree/trunk/retrofit-adapters
- aid: retrofit:retrofit-mock
  name: Retrofit Mock
  description: Provides behavior-simulating implementations of Retrofit interfaces for local testing without requiring a network
    connection.
  humanURL: https://github.com/square/retrofit/tree/trunk/retrofit-mock
  tags:
  - Mock
  - Testing
  properties:
  - type: GitHub
    url: https://github.com/square/retrofit/tree/trunk/retrofit-mock
common:
- type: Website
  url: https://square.github.io/retrofit/
- type: Documentation
  url: https://square.github.io/retrofit/
- type: GitHub
  url: https://github.com/square/retrofit
- type: GitHubOrganization
  url: https://github.com/square
- type: ChangeLog
  url: https://github.com/square/retrofit/blob/trunk/CHANGELOG.md
- type: Issues
  url: https://github.com/square/retrofit/issues
- type: Maven
  url: https://search.maven.org/artifact/com.squareup.retrofit2/retrofit
- type: License
  url: https://github.com/square/retrofit/blob/trunk/LICENSE.txt
- type: JavaDoc
  url: https://square.github.io/retrofit/2.x/retrofit/
- type: Vocabulary
  url: https://raw.githubusercontent.com/api-evangelist/retrofit/refs/heads/main/vocabulary/retrofit-vocabulary.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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