Standards
The open standards behind the agent stack
Agents now plug into tools, other agents, editors and checkouts through a handful of open standards. Each card covers who governs it, the current version, what changed recently and when to reach for it, with a link to the primary source.
Reviewed Oct 5, 2026. Facts are taken from each project's own specification.
Agent ↔ tools and data
Agent ↔ agent
Instructions and know-how
SKILL.md
Supported by 45+ agent productsAgent Skills
Portable folders of instructions, scripts and references that an agent loads only when a task needs them.
Open standard at agentskills.io, originally developed by Anthropic.
AGENTS.md
Read by 20+ coding agentsAGENTS.md
A README for coding agents: build steps, test commands and conventions in one file at the repo root.
Agentic AI Foundation (Linux Foundation). Emerged from OpenAI Codex, Amp, Google Jules, Cursor and Factory.
Agent ↔ editor
Agent commerce
UCP
Shopping spec established; lodging in draft; food comingUniversal Commerce Protocol
Common building blocks for agents to discover products, build carts, check out and handle orders.
Co-developed by Google, Shopify, Amazon, Walmart, Target, Microsoft, Meta, Stripe and others. Apache-2.0.
AP2
Used with UCP for agent checkoutAgent Payments Protocol
Proves that a user really authorized what their agent is buying, using signed mandates.
Initiated by Google in September 2025.