swatchdog.dev
The drift check for AI-built apps.
The brief
#b06ed0 and #b16fd2 are different colors, and an agent can't see that. Swatchdog is a single MCP tool — check_design_drift — that takes a reference token set and code, and returns every off-token color, radius, spacing, and type value, each with the exact token to use instead.
Agents call it on their own output as they build: check, fix, re-check, ship. One connection in Claude, Claude Code, or any MCP client — listed in the Anthropic Connector Directory.
Notes from the build
decisions that heldThe whole product is one deterministic check with a tight contract. Narrow scope is what lets an agent — and the person reviewing the agent — trust it.
Tokens and code travel inside the call; nothing is stored and nothing is modified. It reports drift, it doesn't touch your build.
The reference can be your own tokens — CSS variables, a tokens file, a Tailwind theme — or a curated pack. The check is identical either way.