OpenAPI
The OpenAPI Specification (OAS) is a formal standard for describing HTTP APIs. It enables teams to understand how an API works and how multiple APIs interoperate, generate client code, create tests, apply design standards, and more.
The OpenAPI Specification (OAS) is a formal standard for describing HTTP APIs. It enables teams to understand how an API works and how multiple APIs interoperate, generate client code, create tests, apply design standards, and more.
The Overlay Specification is an auxiliary standard that complements the OpenAPI Specification. An OpenAPI description defines API operations, data structures, and metadata—the overall shape of an API. An Overlay lists a series of repeatable changes to apply to a given OpenAPI description, enabling transformations as part of your API workflows.
The Arazzo Specification is a community-driven, open standard within the OpenAPI Initiative (a Linux Foundation Collaborative Project). It defines a programming-language-agnostic way to express sequences of calls and the dependencies between them to achieve a specific outcome.
AsyncAPI is an open-source, protocol-agnostic specification for describing event-driven APIs and message-driven applications. It serves as the OpenAPI of the asynchronous, event-driven world—overlapping with, and often going beyond, what OpenAPI covers.
APIOps Cycles is a Lean and service design–inspired methodology for designing, improving, and scaling APIs throughout their entire lifecycle. Developed since 2017 and continuously refined through community contributions and real-world projects across industries, APIOps Cycles provides a structured approach to API strategy using a distinctive metro map visualization where stations and lines represent critical aspects of the API lifecycle.
A Postman Collection is a portable JSON artifacts that organizes one or more API requests—plus their params, headers, auth, scripts, and examples—so you can run, share, and automate them in the Postman desktop or web client application. Collections can include folders, collection- and environment-level variables, pre-request and test scripts, examples, mock server definitions, and documentation.
Postman environments are collections of variables that let you easily switch between different configurations (like development, staging, and production server URLs) without manually changing values throughout your API requests.
Backstage’s Software Catalog format is a structured, YAML-based specification that describes software components, services, APIs, resources, and their relationships, enabling teams to discover, document, and manage ownership and lifecycle information in a centralized developer portal.
Bruno collections are organized sets of API requests and environments within the Bruno API client, allowing developers to structure, test, and share their API workflows efficiently.
A Bruno environment is a set of key–value variables that let you switch configurations—such as URLs, tokens, or credentials—so you can run the same API requests across different contexts like development, staging, or production.
A modern, developer-first specification pioneered by Bruno for defining and sharing API collections. Designed for simplicity and collaboration.
The Agent2Agent (A2A) Protocol is an open standard for communication and interoperability among independent—often opaque—AI agent systems. Because agents may be built with different frameworks, languages, and vendors, A2A provides a common language and interaction model.
JSON-RPC is a lightweight, transport-agnostic remote procedure call (RPC) protocol that uses JSON to encode requests and responses. A client sends an object with jsonrpc “2.0”, a method name, optional params (positional or named), and an id; the server replies with either a result or an error (including standardized error codes), and it also supports notifications (no id, no response) and request batching.
MCP (Model Context Protocol) is an open protocol that standardizes how applications provide context to large language models (LLMs). It offers a consistent way to connect AI models to diverse data sources and tools, enabling agents and complex workflows that link models to the outside world.
Apache Parquet is a columnar storage file format designed for efficient data storage and retrieval in big data processing frameworks, optimizing for analytics workloads by storing data column-by-column rather than row-by-row, which enables compression, encoding, and query performance optimizations.
Apache Avro is a data serialization system that provides compact binary encoding of structured data along with schema definitions, enabling efficient data exchange and storage with built-in schema evolution capabilities that allow data structures to change over time while maintaining compatibility between different versions.
The Agent2Agent (A2A) Protocol is an open standard for communication and interoperability among independent—often opaque—AI agent systems. Because agents may be built with different frameworks, languages, and vendors, A2A provides a common language and interaction model.
JSON Schema is a vocabulary for annotating and validating JSON documents. It defines the structure, content, and constraints of data—often authored in either JSON or YAML—and can be leveraged by documentation generators, validators, and other tooling.
Protocol Buffers (protobuf) are Google’s language-neutral, platform-neutral way to define structured data and serialize it efficiently (small, fast). You write a schema in a .proto file, generate code for your language (Go, Java, Python, JS, etc.), and use the generated classes to read/write binary messages.
Schema.org is a collaborative, community-driven vocabulary (launched in 2011 by Google, Microsoft, Yahoo!, and Yandex) that defines shared types and properties to describe things on the web—people, places, products, events, and more—so search engines and other consumers can understand page content.
JSON-LD (JavaScript Object Notation for Linking Data) is a W3C standard for expressing linked data in JSON. It adds lightweight semantics to ordinary JSON so machines can understand what the data means, not just its shape—by mapping keys to globally unique identifiers (IRIs) via a @context. Common features include @id (identity), @type (class), and optional graph constructs (@graph).
Spectral is an open-source API linter for enforcing style guides and best practices across JSON Schema, OpenAPI, and AsyncAPI documents. It helps teams ensure consistency, quality, and adherence to organizational standards in API design and development.
RuleSets are how to configure vacuum to know which rules to run for each specification, and how it should evaluate those rules, and a RuleSet is a style guide with each rule being an individual requirement as a part of the overall guide.
OPA (Open Policy Agent) is a general-purpose policy engine that unifies policy enforcement across your stack—improving developer velocity, security, and auditability. It provides a high-level, declarative language (Rego) for expressing policies across a wide range of use cases.
CSV (Comma-Separated Values) is a simple text format for storing tabular data where each line represents a row and values within rows are separated by commas (or other delimiters).
HTML (HyperText Markup Language) is the standard markup language used to create and structure content on web pages, defining elements like headings, paragraphs, links, images, and forms through a system of tags that web browsers interpret and render as visual displays.
JDBC (Java Database Connectivity) is a Java API that provides a standard interface for Java applications to connect to and interact with relational databases, allowing developers to execute SQL queries, retrieve results, and manage database transactions in a database-agnostic way.
JSON (JavaScript Object Notation) is a lightweight, text-based data interchange format that uses human-readable syntax with key-value pairs, arrays, and primitive data types (strings, numbers, booleans, null) to represent structured data.
Markdown is a lightweight markup language that uses plain text formatting syntax (such as asterisks for emphasis, hashes for headings, and brackets for links) to create formatted documents that are easy to read in raw form and can be converted to HTML and other formats.
ODBC (Open Database Connectivity) is a standard API specification that provides a database-agnostic interface for applications to connect to and interact with various relational database management systems through database-specific drivers, enabling cross-platform database access without requiring application code changes.
YAML (“YAML Ain’t Markup Language”) is a human-friendly data serialization format used for configuration and data exchange, built around indentation to express structure (mappings/objects, sequences/arrays, and scalars). It supports comments (#), multi-document streams (—), anchors/aliases for reuse (&id, *id), and optional type tags.
XML (eXtensible Markup Language) is a text-based, Unicode-friendly format for representing structured data using nested elements (tags) and attributes, making documents both human- and machine-readable. It’s “extensible” because you define your own vocabulary (element and attribute names), organize data hierarchically, and use namespaces to avoid naming collisions.
OAuth 2.0 is an industry-standard protocol that enables secure, delegated access to APIs without requiring users to share their passwords with applications. Instead of handing over credentials, a user authorizes a trusted identity provider—such as Google, Microsoft, or an enterprise login system—to issue short-lived access tokens to a client application.
A JSON Web Token (JWT) is a compact, URL-safe token format used to securely transmit information between parties as a JSON object, commonly used for authentication and authorization in web applications.
HTTP (Hypertext Transfer Protocol) is a stateless application-layer protocol that defines how web clients and servers format and exchange requests and responses over the internet.
HTTP/2 is a binary, multiplexed version of HTTP that uses streams, header compression (HPACK), and optional server push to reduce latency and improve performance over a single TCP connection.
HTTP/3 is the latest HTTP version that runs over QUIC (on UDP), providing multiplexed streams with built-in TLS 1.3 and connection migration to avoid TCP head-of-line blocking and improve performance.
APIs.json is a machine-readable specification that API providers use to describe their API operations—much like sitemap.xml describes a website. It offers an index of internal, partner, and public APIs that includes not only machine-readable artifacts (OpenAPI, JSON Schema, etc.) but also traditionally human-readable assets such as documentation, pricing, and terms of service.
API Commons is a collection of open-source building blocks for API operations. It began as a machine-readable way to define the parts of an API, and works in concert with APIs.json to translate human-readable aspects of your API program into machine-readable artifacts that can standardize and automate your ecosystem.
APIExamples format is Microcks’ own specification format for defining examples intended to be used by Microcks mocks.
A vCard is a digital file format used to store and exchange contact information, such as names, phone numbers, email addresses, and addresses, in a standardized, portable way.
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