Schema validator

A skill for validating that design token files conform to their expected format — DTCG 2025.10 (token files and resolver documents), Style Dictionary 3, 4 or 5, Tokens Studio, or a custom schema. Catches structural issues before they break build pipelines, cause silent failures, or produce incorrect output.

Before you begin: verify references

Confirm that every path in this skill's frontmatter references: exists relative to this SKILL.md. If any is missing, stop: the install is incomplete, usually because a flattening installer (for example npx skills install) dropped the repo-root knowledge-notes/ directory. Tell the user to reinstall by a method in 1-INSTALL.md and run verify-install.sh from the install root. Proceed without the references only if the user explicitly says to, and then say in the output that it was produced without the pack's reference material.

Context

Token files are infrastructure. When a token file is malformed — a missing $type declaration, a $value that resolves to nothing, an alias that points to a deleted token — the failure mode is rarely loud. The build might still succeed. The wrong value might ship. The design intent might be silently lost.

Schema validation is the first line of defence. It answers a simple question: do these files meet the structural contract they claim to meet? A DTCG file must have $value on every token. A Style Dictionary file must have valid reference syntax. A Tokens Studio export must preserve group hierarchy.

This skill is not about naming conventions or architectural quality — those belong in token-audit. This skill is about structural integrity: can the file be parsed, transformed, and consumed by downstream tools without error?

Boundaries

This skill validates token file structure only. It does not assess naming quality (use naming-audit), token architecture health (use token-audit), or token usage in code (use token-compliance). If the token source format is not recognisable as DTCG, Style Dictionary, Tokens Studio, or a declared custom schema, ask the user to identify the format before proceeding. If no token files are provided or accessible, there is nothing to validate — stop and confirm the file location with the user.