Topics / #specification

Specification projects on GitHub

Technical specifications and language feature proposals.

As of , the most-starred Specification projects on GitHub are skills (181.6K stars), OpenSpec (72.2K stars) and wtfjs (37.7K stars). GitHub.Locker tracks 40 Specification repositories with 824.4K stars combined. The fastest-growing on October 16 was skills, with +217 stars in a day.

40Projects
824.4KStars in total
+447Stars in a day
Browse in the catalog →github.com/topics/specification ↗

Hot right now

Most stars gained in a day · Oct 16

+217

skills

anthropics/skills · ★ 181.6K

This is Anthropic's public repository of Agent Skills for Claude: folders of instructions, scripts, and resources that Claude loads dynamically to get better at specific tasks like document creation, data analysis, or enterprise workflows.

+103

OpenSpec

Fission-AI/OpenSpec · ★ 72.2K

OpenSpec is a spec-driven development tool that adds a lightweight spec layer so you and your AI coding assistant agree on requirements before any code is written.

+32

agentskills

agentskills/agentskills · ★ 26.2K

An open format for giving AI agents new capabilities and expertise: a skill is a folder with a SKILL.md file of instructions, plus optional scripts, templates and reference materials.

+19

agents.md

agentsmd/agents.md · ★ 25K

AGENTS.md is a simple, open Markdown format for giving AI coding agents project-specific context and instructions, functioning like a README but written specifically for agents.

The all-time top

40 projects · by stars

  1. #1 · anthropics/skills

    skills

    This is Anthropic's public repository of Agent Skills for Claude: folders of instructions, scripts, and resources that Claude loads dynamically to get better at specific tasks like document creation, data analysis, or enterprise workflows.

    181.6K
  2. #2 · Fission-AI/OpenSpec

    OpenSpec

    OpenSpec is a spec-driven development tool that adds a lightweight spec layer so you and your AI coding assistant agree on requirements before any code is written.

    72.2K
  3. #3 · denysdovhan/wtfjs

    wtfjs

    It is a curated handbook (WTFJS) of funny and tricky JavaScript examples, each snippet showing surprising behavior followed by a step-by-step explanation and links to the ECMAScript spec.

    37.7K
  1. 4

    OpenAPI-Specification

    31.3KOAI/OpenAPI-Specification · Markdown

    The OpenAPI Specification (OAS) is a community-driven open standard from the OpenAPI Initiative, a Linux Foundation Collaborative Project: a standard, programming language-agnostic way to describe HTTP APIs.

  2. 5

    es6features

    29Klukehoban/es6features

    A one-page overview of ECMAScript 6 (ES2015) — the major update to JavaScript and the first since ES5 was standardized in 2009.

  3. 6

    todomvc

    29Ktastejs/todomvc · JavaScript

    TodoMVC implements the same Todo application in dozens of JavaScript frameworks and libraries so you can compare them side by side before picking one for a real project.

  4. 7

    design.md

    28.4Kgoogle-labs-code/design.md · TypeScript

    DESIGN.md is a format specification for describing a visual identity (colors, typography, layout, components) so coding agents have a persistent, structured understanding of a design system.

  5. 8

    agentskills

    26.2Kagentskills/agentskills · Python

    An open format for giving AI agents new capabilities and expertise: a skill is a folder with a SKILL.md file of instructions, plus optional scripts, templates and reference materials.

  6. 9

    A2A

    26.2Ka2aproject/A2A · Shell

    The Agent2Agent (A2A) protocol is an open standard that lets gen AI agents built on different frameworks and run by different companies talk to each other — discovering capabilities, negotiating how to interact, and collaborating on long-running tasks as agents, not just as tools.

  7. 10

    agents.md

    25Kagentsmd/agents.md · TypeScript

    AGENTS.md is a simple, open Markdown format for giving AI coding agents project-specific context and instructions, functioning like a README but written specifically for agents.

  8. 11

    api-guidelines

    23.3Kmicrosoft/api-guidelines

    A collection of guidelines published by Microsoft for designing consistent, well-behaved RESTful web APIs, shared publicly to foster dialogue in the broader API community.

  9. 12

    onnx

    21.6Konnx/onnx · Python

    ONNX (Open Neural Network Exchange) is an open standard for machine learning interoperability — an open ecosystem and format for AI models, both deep learning and traditional ML.

  10. 13

    toml

    20.6Ktoml-lang/toml

    TOML (Tom's Obvious, Minimal Language) is a minimal configuration file format designed to be readable at a glance, with semantics obvious enough to map cleanly onto a hash table. This repository holds the in-development TOML specification itself.

  11. 14

    whitepaper

    20.1Kunicitynetwork/whitepaper · TeX

    This repository hosts the Unicity protocol whitepaper and its companion papers, describing the 'Autonomous Agentic Internet', the protocol's system model, tokenomics, and how the network components fit together.

  12. 15

    proposals

    19.2Ktc39/proposals

    The official TC39 repository that tracks every proposal for future JavaScript (ECMAScript) features — a living index of what is being considered for the next versions of the language standard.

  13. 16

    css-modules

    18Kcss-modules/css-modules

    CSS Modules are CSS files where class names and animation names are scoped locally by default. This repository is the project's documentation rather than an implementation.

  14. 17

    diem

    16.7Kdiem/diem · Rust

    Diem Core is the prototype implementation of the Diem blockchain (formerly Libra) — a decentralized, programmable distributed ledger meant to provide financial infrastructure for a global payment network.

  15. 18

    swift-evolution

    15.9Kswiftlang/swift-evolution · Markdown

    This is the Swift Evolution repository: it tracks how the Swift programming language, its standard library, and its package manager evolve, one proposal at a time.

  16. 19

    ecma262

    15.7Ktc39/ecma262 · HTML

    It is the source repository for the current draft of ECMA-262, the ECMAScript (JavaScript) Language Specification, maintained by TC39. The source is processed to generate the human-readable edition of the spec.

  17. 20

    sass

    15.4Ksass/sass · TypeScript

    Sass is a CSS extension language that adds nested rules, variables, mixins, and selector inheritance, compiling down to standard CSS. This particular repo, however, holds the language's specifications and proposals rather than an implementation.

  18. 21

    graphql-spec

    14.6Kgraphql/graphql-spec · HTML

    This is the official GraphQL specification: the document that defines the GraphQL query language, type system, validation rules, and execution semantics for building APIs.

  19. 22

    scala

    14.6Kscala/scala · Scala

    This is the official Scala 2 repository: the source for the Scala 2 compiler, standard library, and language specification. Bug reports go to scala/bug, and Scala 3 is developed separately at scala/scala3.

  20. 23

    language-server-protocol

    13Kmicrosoft/language-server-protocol · TypeScript

    This is the home of the Language Server Protocol (LSP), Microsoft's specification that defines a common protocol for language servers — the components editors and IDEs talk to for language features like autocomplete.

  21. 24

    csharplang

    12.7Kdotnet/csharplang · C#

    The official repo where the C# language itself is designed: new language features are proposed, debated, adopted and specified here by the C# Language Design Team (LDT), in coordination with Roslyn, the project that implements C#.

  22. 25

    fig-standards

    12.5Kphp-fig/fig-standards

    This is the PHP-FIG repository holding the PSR (PHP Standard Recommendations) specifications, proposed and approved by the PHP Framework Interoperability Group to standardize common patterns across PHP frameworks and libraries.

  23. 26

    nostr

    12.1Knostr-protocol/nostr

    Nostr (Notes and Other Stuff Transmitted by Relays) is an open protocol for a censorship-resistant global social network. This repo holds the idea and spec, not an app.

  24. 27

    design

    11.6KWebAssembly/design

    This repository is part of the WebAssembly Community Group and hosts the issue tracker for phase 0 proposals, a discussion forum for questions, and a collection of high-level non-normative design documents about WebAssembly.

  25. 28

    bips

    11Kbitcoin/bips · Wikitext

    This is the official repository of Bitcoin Improvement Proposals (BIPs) — design documents and standards for changing and extending Bitcoin, from consensus rules to wallet formats. The repo serves as both the publication medium and the permanent archive for these proposals.

  26. 29

    spec

    10.8Kulid/spec

    This is the canonical specification for ULID (Universally Unique Lexicographically Sortable Identifier), a 128-bit identifier format designed as a sortable, URL-safe alternative to UUID.

  27. 30

    log

    10.4Kphp-fig/log · PHP

    This is the PSR-3 standard package: a set of interfaces, classes and traits (centered on Psr\Log\LoggerInterface) that describe what a PHP logger should look like, so different libraries can share a common logging contract.

  28. 31

    fantasy-land

    10.2Kfantasyland/fantasy-land · JavaScript

    Fantasy Land (aka 'Algebraic JavaScript Specification') is a specification defining how common algebraic structures in JavaScript — equality, ordering, concatenation, mapping, chaining — must behave, so that types from different libraries can interoperate.

  29. 32

    container

    10Kphp-fig/container · PHP

    The official PHP-FIG repository of interfaces for PSR-11, the Container Interface standard. It defines the abstractions that describe the components of a Dependency Injection Container.

  30. 33

    rfcs

    4.2Kastrid-runtime/rfcs · Python

    This repository holds RFCs (design proposals) that define any substantial change to the contract between Astrid's kernel and user-space, covering the host ABI, IPC protocol, capability model, manifest schema, VFS semantics, capsule interface standards, and the SDK's public API.

  31. 34

    open-knowledge-format

    990GoogleCloudPlatform/open-knowledge-format · HTML

    OKF (Open Knowledge Format) is a vendor-neutral spec from Google Cloud for representing catalog knowledge as plain markdown files with YAML frontmatter, not tied to any specific agent, framework, or model provider. This repo also ships a reference agent that produces OKF bundles and a visualizer that renders them.

  32. 35

    agentmemoryrepo

    797AgentMemoryRepo/agentmemoryrepo

    Agent Memory Repo is an open spec that lets a coding agent save what it learns about you or your project in a plain git repo of Markdown files, so that knowledge survives into the agent's next session.

  33. 36

    hello-sdd

    719mouredev/hello-sdd · Python

    This is MoureDev's course on Spec-Driven Development (SDD): building software with AI agents starting from an agreed specification instead of improvising prompts. The repo holds the course's reusable templates plus a complete example project built step by step using the SDD method.

  34. 37

    interop

    528web-platform-tests/interop · JavaScript

    An ongoing effort by browser makers to make the web more interoperable: each year they pick key focus areas and publicly score how well browsers implement them. It is part of the web-platform-tests project.

  35. 38

    AgentMeasure

    218roy-tong/AgentMeasure · Python

    AgentMeasure is an open measurement layer for AI-agent usage: a free CLI and SDK that audit Codex and Claude Code session logs and verify that agent metrics and metering numbers mean what their labels claim.

  36. 39

    spec

    204ooni/spec

    This is OONI Spec, the repository where OONI openly specifies its testing methodology: the experiments (nettests) it runs, the backend components used for testing, and the data formats for the results.

  37. 40

    dsh-std

    158T-Auto/dsh-std · TypeScript

    DSH Standard is a set of universal interoperability protocols that lets DSH plugins, background runtimes, and different user interfaces (TUI, Web UI, desktop apps, headless daemons) decouple from each other and work together.

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