Mintlify introduced skill.md, an open standard file that lives alongside documentation to guide AI agents on using a product. It's being integrated into 20+ major coding agents like Claude Code and Cursor via Vercel's CLI. The company deprecated its earlier install.md proposal, citing better momentum and fit for the use case.

The core problem is that AI agents, despite having access to full documentation, often write poor code because human-oriented docs are scattered and dense. skill.md consolidates essential context—like capabilities, limitations, and best practices—into a concise format agents can reliably use. Mintlify regenerates this file automatically to keep it current with documentation updates.

The spec is flexible, but Mintlify's implementation uses decision tables to encode tribal knowledge, explicit boundaries to prevent impossible tasks, and a 'gotchas' section for common errors. It serves as a cheat sheet, linking out to full docs via llms.txt for deeper context. The goal is to improve agent performance by providing structured, up-to-date guidance.