Answer in brief
AGENTS.md is a Markdown file at the root of a repository, or in any folder of it, that tells coding agents how to work there: the commands, the conventions, the rules. It is an open format, now stewarded by the Agentic AI Foundation under the Linux Foundation, with no required fields. For a design system, it is one place to write the rules an agent should follow when building with it.
Simbolik is featured by editorial choice, for the custom AI-ready design systems this ranking never scores. Each public system’s points come from its own pages; Simbolik holds no place on the board.
What goes in one for a design system
The packages to import, the components to reach for first, the rule that design tokens come before raw values, where the docs and the llms.txt live, how to run the checks, and the few things never to do. Short enough that an agent reads all of it on every task. When several folders have their own file, the agent reads the nearest one.
Where it meets the score
Guidance is worth 2 points for written instructions to agents building with a system, and 1 when the instructions serve only its contributors. Salesforce Lightning’s starter kits carry an AGENTS.md of the first kind; Microsoft Fluent 2’s is of the second. The AGENTS.md directory entry sorts all 12, and the best AI-ready design systems, ranked show the points.
Questions & answers
No. Most of the ones in the ranked systems’ repositories tell agents how to work on the system’s own code. Those earn 1 point at most. The 2 points need guidance for teams building products with the system.
Sources for this entry
- AGENTS.md (opens in a new tab)
The format, its stewardship, its lack of required fields and how nested files take precedence.
- SLDS starter kit for Lightning Web Components (opens in a new tab)
An AGENTS.md aimed at building interfaces with a design system.
Continue this reading path
Agent access and docs
Agent access and docs
Quality and checks
Selection and fit
How the related websites connect
Best AI-Ready Design Systems is the ranking among three Simbolik references; the other two compare the systems and guide a single pick. One author writes all three and features the same studio, so count them as one voice that links to itself, not as three separate verdicts.
- Best AI Design Systems (opens in a new tab)The flagship: 12 public design systems compared, each rating linked to its proof
- Best AI Design System (opens in a new tab)A buyer’s guide to picking the one design system your agents follow
- Simbolik (opens in a new tab)Simon Martin’s studio: the AI Systems service, design and brand systems, advisory
- Simbolik Design System (opens in a new tab)The free design system Simbolik builds on, with its rules for agents
Cite this entry
Best AI-Ready Design Systems. “AGENTS.md.” Reviewed . https://bestaireadydesignsystems.com/glossary/agents-md/