10 GitHub repos that Anthropic, OpenAI, and Google quietly open-sourced for the public in 2026. In 2026, the three biggest AI labs on Earth started giving their best work away. Most people don’t know. Bookmark this list — the ones who do are already building. 1. anthropics/skills Anthropic’s official Skills repository. The exact patterns Anthropic uses internally to extend Claude. Repo → https://github.com/anthropics/skills… 2. openai/openai-agents-python OpenAI’s official multi-agent framework. 26K+ stars. The same SDK OpenAI’s own engineers use. Repo → https://github.com/openai/openai-agents-python… 3. google/adk-python Google’s Agent Development Kit. The official toolkit for building and deploying agents. Repo → https://github.com/google/adk-python… 4. anthropics/courses Free educational courses from Anthropic. Constitutional AI, prompt engineering, agent design straight from the team that built Claude. Repo → https://github.com/anthropics/courses… 5. openai/openai-cookbook OpenAI’s collection of working production recipes. RAG, evals, fine-tuning, agent loops. Repo → https://github.com/openai/openai-cookbook… 6. google/generative-ai-python Google’s official Gemini SDK. Direct access to the models powering Google products. Repo → https://github.com/google/generative-ai-python… 7. anthropics/claude-code The official Claude Code repository. The AI coding tool used inside FAANG, OpenAI, and Anthropic itself. Repo → https://github.com/anthropics/claude-code… 8. openai/evals OpenAI’s open-source framework for benchmarking LLMs. The same evaluation infrastructure they use internally. Repo → https://github.com/openai/evals 9. google-research/google-research Google Research’s official code dump. Working implementations across ML, NLP, and vision. Repo → https://github.com/google-research/google-research… 10. anthropics/anthropic-cookbook Anthropic’s working notebooks. Real production patterns for building with Claude, straight from the team. Repo → https://github.com/anthropics/anthropic-cookbook… Here’s the wildest part: The companies fighting for trillions are quietly arming you for free. Anthropic’s internal patterns. OpenAI’s evaluation infrastructure. Google’s research code. The exact tools their own engineers use, sitting on GitHub, free to clone today. You don’t need a contract with Microsoft, an API deal with OpenAI, or a Google enterprise license. You need a laptop, a weekend, and these 10 repos. Most people will scroll past this. The ones who don’t will compound. Save this before you forget. 100% free. 100% open source.

anthropics/skills

Source: https://github.com/anthropics/skills

Note: This repository contains Anthropic’s implementation of skills for Claude. For information about the Agent Skills standard, see agentskills.io.

Skills

Skills are folders of instructions, scripts, and resources that Claude loads dynamically to improve performance on specialized tasks. Skills teach Claude how to complete specific tasks in a repeatable way, whether that’s creating documents with your company’s brand guidelines, analyzing data using your organization’s specific workflows, or automating personal tasks.

For more information, check out:

• What are skills?
• Using skills in Claude
• How to create custom skills
• Equipping agents for the real world with Agent Skills

About This Repository

This repository contains skills that demonstrate what’s possible with Claude’s skills system. These skills range from creative applications (art, music, design) to technical tasks (testing web apps, MCP server generation) to enterprise workflows (communications, branding, etc.).

Each skill is self-contained in its own folder with a SKILL.md file containing the instructions and metadata that Claude uses. Browse through these skills to get inspiration for your own skills or to understand different patterns and approaches.

Many skills in this repo are open source (Apache 2.0). We’ve also included the document creation & editing skills that power Claude’s document capabilities under the hood in the skills/docx, skills/pdf, skills/pptx, and skills/xlsx subfolders. These are source-available, not open source, but we wanted to share these with developers as a reference for more complex skills that are actively used in a production AI application.

Disclaimer

These skills are provided for demonstration and educational purposes only. While some of these capabilities may be available in Claude, the implementations and behaviors you receive from Claude may differ from what is shown in these skills. These skills are meant to illustrate patterns and possibilities. Always test skills thoroughly in your own environment before relying on them for critical tasks.

Skill Sets

• ./skills: Skill examples for Creative & Design, Development & Technical, Enterprise & Communication, and Document Skills
• ./spec: The Agent Skills specification
• ./template: Skill template

Try in Claude Code, Claude.ai, and the API

Claude Code

You can register this repository as a Claude Code Plugin marketplace by running the following command in Claude Code:

/plugin marketplace add anthropics/skills

Then, to install a specific set of skills:

1. Select Browse and install plugins
2. Select anthropic-agent-skills
3. Select document-skills or example-skills
4. Select Install now

Alternatively, directly install either Plugin via:

/plugin install document-skills@anthropic-agent-skills
/plugin install example-skills@anthropic-agent-skills

After installing the plugin, you can use the skill by just mentioning it. For instance, if you install the document-skills plugin from the marketplace, you can ask Claude Code to do something like: “Use the PDF skill to extract the form fields from path/to/some-file.pdf”

Claude.ai

These example skills are all already available to paid plans in Claude.ai.

To use any skill from this repository or upload custom skills, follow the instructions in Using skills in Claude.

Claude API

You can use Anthropic’s pre-built skills, and upload custom skills, via the Claude API. See the Skills API Quickstart for more.

Creating a Basic Skill

Skills are simple to create - just a folder with a SKILL.md file containing YAML frontmatter and instructions. You can use the template-skill in this repository as a starting point:

---
name: my-skill-name
description: A clear description of what this skill does and when to use it
---

# My Skill Name

[Add your instructions here that Claude will follow when this skill is active]

## Examples
- Example usage 1
- Example usage 2

## Guidelines
- Guideline 1
- Guideline 2

The frontmatter requires only two fields:

• name - A unique identifier for your skill (lowercase, hyphens for spaces)
• description - A complete description of what the skill does and when to use it

The markdown content below contains the instructions, examples, and guidelines that Claude will follow. For more details, see How to create custom skills.

Partner Skills

Skills are a great way to teach Claude how to get better at using specific pieces of software. As we see awesome example skills from partners, we may highlight some of them here:

• Notion - Notion Skills for Claude