February 17, 2026·Tutorial·2 min read

14 Hosted MCP Tools That Make AI Understand Your Design System

By Conan McNicholl

Fragments MCP is now hosted by Fragments Cloud. The package name remains @fragments-sdk/mcp, but AI clients connect to a remote endpoint instead of starting a local stdio process:

https://app.usefragments.com/api/mcp

Interactive RC clients authenticate through MCP OAuth discovery. Headless clients authenticate with a Fragments Cloud API key:

Authorization: Bearer <FRAGMENTS_API_KEY>

The endpoint exposes 14 tools:

Tool	Purpose
`catalog/list_components`	List components in the active Cloud catalog
`catalog/list_tokens`	List tokens with category/search filters
`catalog/get_component`	Fetch one component by id or name
`findings/list`	List Cloud governance findings
`findings/summary`	Aggregate findings by severity, status, category, rule, and file
`findings/for_file`	Return open findings for one file
`findings/explain`	Explain a finding and suggested fix
`lint/file`	Lint supplied file content without server disk access
`tokens/suggest`	Suggest design tokens for CSS authoring
`fix/suggest_patch`	Return a deterministic patch suggestion for the agent to apply
`fix/swap_to_canonical`	Suggest raw HTML to canonical component swaps
`govern/scan_repo`	Create a task for a remote governance scan
`autofix/create_pr`	Create a task for an autofix PR
`suggestions/analyze`	Create a task for AI suggestion analysis

The Agent Loop

Use a short loop for UI work:

Query catalog/list_components and catalog/get_component before choosing primitives.
Ask catalog/list_tokens or tokens/suggest before writing raw CSS values.
Run lint/file on unsaved editor content.
Pull relevant production context with findings/for_file or findings/list.
Ask fix/suggest_patch or fix/swap_to_canonical for deterministic next steps.

The server never reads or writes your filesystem. The agent owns disk I/O and applies patches locally.

Apps And Tasks

Fragments MCP also exposes visual Apps as ui:// resources attached to normal tool metadata. There are no fake apps/list or apps/render tools.

Long-running operations use MCP Tasks. govern/scan_repo, autofix/create_pr, and suggestions/analyze create pollable task handles when the client advertises Tasks support.

Setup

Use this config shape for clients that support remote HTTP MCP servers:

{
  "mcpServers": {
    "fragments": {
      "type": "http",
      "url": "https://app.usefragments.com/api/mcp",
      "headers": {
        "Authorization": "Bearer ${FRAGMENTS_API_KEY}"
      }
    }
  }
}

See the MCP Tools docs for the current setup details.

Conan McNichollFounder

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