APIs.json Blog

News and updates about the APIs.json open source API discovery format and the API discovery ecosystem.

The Anatomy of Mastercard's apis.yml File — A 4,383-Line Worked Example
May 05, 2026

The Anatomy of Mastercard's apis.yml File — A 4,383-Line Worked Example

Most APIs.json files in the wild describe a single API or a handful of APIs. They're useful examples, but they don't show what the format looks like at scale — what an APIs.json file describing a hundred APIs across a...
APIs.jsonapis.ymlMastercardAPI discovery
Read more →
What's New in APIs.json 0.19
May 03, 2026

What's New in APIs.json 0.19

APIs.json 0.19 is the current stable version of the format, and it represents a meaningful step forward in how we express the operational context of an API alongside its technical contracts. If you last looked at APIs...
APIs.jsonAPI discoveryspecificationversioning
Read more →
What's New in APIs.json 0.20
May 02, 2026

What's New in APIs.json 0.20

APIs.json 0.20 is the largest vocabulary expansion in the specification's history. The type field on each property entry in an APIs.json file is how tooling, indexers, and AI agents understand what kind of thing is be...
APIs.jsonSpecificationAPI DiscoveryVersioning
Read more →
What's New in APIs.json 0.21
May 02, 2026

What's New in APIs.json 0.21

APIs.json 0.21 introduces a new category of property types: financial operations and sustainability. As API consumption at enterprise scale has matured, two things have become clear. First, organizations need machine-...
APIs.jsonSpecificationAPI DiscoveryFinOps
Read more →
Indexing Spec-Driven Integrations: When the Spec Is the Integration
April 21, 2026

Indexing Spec-Driven Integrations: When the Spec Is the Integration

APIs.json indexes APIs. The format provides a machine-readable declaration of what APIs exist, where their documentation lives, and how to access them. It solves the discovery problem at the API layer. Spec-Driven In...
Read more →
Pushing APIs.json V0.19
November 06, 2024

Pushing APIs.json V0.19

We have accumulated a number of additions to the spec lately based upon work on APIs.io APIs, but also profiling new APIs. You can find a list of all the new features on Github as issues for v0.19. The most notable a...
Read more →
Considering Some New APIs.json Types
July 07, 2024

Considering Some New APIs.json Types

I am evaluating all of the enums for APIs.json before I plan for the next version. One of the enumerators that haven’t been updated in a while, but has some interesting changes on the table is the type property. To da...
Read more →
A New Website for APIs.json
June 30, 2024

A New Website for APIs.json

It was time for an overhaul of the APIs.json website. We wanted to align it with a makeover coming for API Commons, as well as with APIs.io. It has been about four years since we overhauled the website, and it used a ...
Read more →
A Proposal for APIs.json Version 0.17
February 24, 2024

A Proposal for APIs.json Version 0.17

We have posted a draft proposal for APIs.json 0.17 based upon the work we've been doing with APIs.io over the last couple of months. The project has been dormant for a while, but with renewed investment in APIs.io, we...
Read more →
The Future of APIs.json (2020 Edition)
September 06, 2020

The Future of APIs.json (2020 Edition)

This website and the conversation around APIs.json has been dormant for a couple of years. This was due to acquisitions, job changes, and just not enough time to invest in the specification beyond just putting it to ...
Read more →
APIs.json Is An Index For API Operations
March 01, 2016

APIs.json Is An Index For API Operations

As part of the latest wave of work around the APIs.json format We wanted to take some time to help folks better understand exactly what APIs.json is, and what it can do for API providers, consumers, as well as the fa...
Read more →
Setting rel=api Into Motion With Latest APIs.json Release
July 23, 2015

Setting rel=api Into Motion With Latest APIs.json Release

Bruno Pedro (@bpedro) who has been building APIs.json into his API Changelog service, made a pull request to the specification recently, pushing forward the link relation conversation for APIs.json. As listed in the s...
Read more →
Quantifying A Minimum Viable API Footprint Definition As Real APIs.json Driven Portal
April 20, 2015

Quantifying A Minimum Viable API Footprint Definition As Real APIs.json Driven Portal

I wrote a post the other day laying out what I'd consider a minimum viable footprint for API operations. My vision of just exactly what an API is, has gone beyond just the technical, ever since I started API Evangeli...
Read more →
A Breakdown Of My Dream APIs.json File
March 07, 2015

A Breakdown Of My Dream APIs.json File

I'm continuing my work, to help people understand what APIs.json is, and the varying ways that it can be put to use. My post the other week, breaking down Fitbits APIs.json file is a good example of where to get sta...
Read more →
A Minimum Viable APIs.json File For Your APIs
February 08, 2015

A Minimum Viable APIs.json File For Your APIs

I'm continuing my work to help people understand what APIs.json is, and the varying ways that it can be put to use. My post the other day, breaking down Fitbits APIs.json file is a good example of where to get start...
Read more →
Breaking Down The Fitbit APIs.json File
January 31, 2015

Breaking Down The Fitbit APIs.json File

The quantified-self API Fitbit recently added an APIs.json for their domain. Their usage of APIs.json is a perfect, dead-simple, introductory example of how APIs can start putting APIs.json for their API platform. To ...
Read more →
Using APIs.json For My Microservice Navigation And Discovery
January 28, 2015

Using APIs.json For My Microservice Navigation And Discovery

I’m rebuilding my underlying architecture using microservices and docker containers, and the glue I’m using to bind it all together is APIs.json. I’m not just using APIs.son to deliver on discoverab...
Read more →
My Experiences Generating API Server or Client Code Using Swagger
January 26, 2015

My Experiences Generating API Server or Client Code Using Swagger

When you start talking about generating server or client side code for APIs, using machine readable API definition formats like Swagger or API Blueprint, many technologists feel compelled to let you know, that at som...
Read more →
REST API Design: Bridging What We Have, To The Future, By Organizing The JSON Junk Drawer
January 21, 2015

REST API Design: Bridging What We Have, To The Future, By Organizing The JSON Junk Drawer

API storyteller J(a)son Harmon (@jharmn) has a new YouTube channel up called API Workshop. He's going to be publishing regular API design workshop episodes, with the latest one titled REST API Design: Avoid future pr...
Read more →
What Exactly Is APIs.json?
January 05, 2015

What Exactly Is APIs.json?

As I travel around talking to folks about APIs, I spend as much time as I can, educating folks about APIs.json. In the course of my evangelism, I’m constantly reminded how little people, who have even heard, an...
Read more →
Next Stable Version of APIs.json + APIs.io Is Ready - Are Your APIs Discoverable?
October 08, 2014

Next Stable Version of APIs.json + APIs.io Is Ready - Are Your APIs Discoverable?

Steve (@njyx), Nicolas (@picsoung), and I have been working hard to gather all the feedback from some very smart folks on the API.json format. Now we are stoked to finally announce that we have the 0.14 version ready...
Read more →
Trade.gov Using APIs.json And Added To APIs.io
October 06, 2014

Trade.gov Using APIs.json And Added To APIs.io

I've been a big proponent of APIs in the federal government, and it makes me really happy to see Developer.Trade.Gov using APIs.json to provide an inventory of APIs available at the federal agency dedicated to streng...
Read more →
An APIs.json Collection Of API Resources Across Your Public, Partner Or Internal Resources
August 19, 2014

An APIs.json Collection Of API Resources Across Your Public, Partner Or Internal Resources

APIs.json was designed to be a versatile API discovery format, not just a format for public API discovery via search engines like APIs.io. An APIs.json is meant to be a machine readable index of APIs within a single ...
Read more →
The Power In API Discovery For APIs.json Will Be In The API URL Type
July 09, 2014

The Power In API Discovery For APIs.json Will Be In The API URL Type

An APIs.json file lives in the root of any domain, or subdomain, and provides references to a collection of API resources. The APIs.json is meant to be a lightweight framework, where someone can build a collecti...
Read more →
Multiple Types of APIs.json For Discovery
June 18, 2014

Multiple Types of APIs.json For Discovery

I’m working through thoughts around a suggestion for future versions of APIs.json API discovery format, and as I do with other things I’m trying to make sense of, I wanted to write a blog post on API...
Read more →
Announcing APIs.json At Gluecon 2014
May 20, 2014

Announcing APIs.json At Gluecon 2014

One of our favorite events to attend is Gluecon in Broomfield, CO. Eric Norlin and crew has done an amazing job of pulling together the leading technologists, into an intimate venue, where they can discuss the latest...
Read more →
Solving The Problem Of API Discovery
May 20, 2014

Solving The Problem Of API Discovery

API discovery has not changed much since 2005, when John Musser launched ProgrammableWeb, the API directory we've all come to know and love. In 2014 (9 years later), we have Mashape and a handful of other API directo...
Read more →