@iyulab/u-board-mcp

An MCP server that lets an AI assistant read and draw the boards of a U-Board workspace — its own words to the assistant are in the tools it offers, starting with describe({ topic: "rules" }).

It talks to a U-Board server with a workspace API token: in the console, open the workspace settings, and under API 토큰 make a token (write to draw, read to look). The token acts as you, in that workspace only, and never handles a data source's credentials — you enter those in the console.

Run it

UBOARD_URL=https://board.example.com UBOARD_TOKEN=ubt_… npx -y @iyulab/u-board-mcp

With Claude Code:

claude mcp add u-board --env UBOARD_URL=https://board.example.com --env UBOARD_TOKEN=ubt_… -- npx -y @iyulab/u-board-mcp

In a client's JSON configuration:

{
  "mcpServers": {
    "u-board": {
      "command": "npx",
      "args": ["-y", "@iyulab/u-board-mcp"],
      "env": { "UBOARD_URL": "https://board.example.com", "UBOARD_TOKEN": "ubt_…" }
    }
  }
}

Tools

| Tool | What it does | |---|---| | describe | What a board can hold and how to write one: rules (read first — how the tools change a board, then the board language), kind:<name> (a kind of part in full — its options with their types and defaults; several by commas, kind:stat,chart.bar, up to 8 in one read), schema (with a JSON Pointer for one part). | | list_boards | The workspace's boards. | | get_board | A board, or one part of it by JSON Pointer (/parts/pump), with its revision. | | create_board | A new board of a kind (grid or canvas), empty or with a first board. | | patch_board | Changes part of a board with a JSON Patch (RFC 6902) on a revision; answers the new revision and advice. | | rename_board | Renames a board; its id, share links and history stay. | | delete_board | Deletes a board for good (marked destructive, so a client can ask first). A data source is removed in the console. | | validate | Checks a board, a board with a patch, or — with neither — the board as it is saved, without saving. | | look | A picture of a saved board as its viewers see it, with what went wrong while drawing; focus one part (/parts/<id>), or appearance the other paper. Needs Chrome or Edge on this computer, or UBOARD_BROWSER. | | list_sources | The workspace's data sources — never a credential; a static one with the paths it answers and whether its answers are example data. | | sample_source | What a source's response looks like: each value's JSON Pointer, type and example, and the fields that tell a list's items apart. | | create_source | A data source that needs no credential — an API, or one that answers what is stored in it by path (example values when no source has them yet); one that needs a credential is made by a person in the console. |

Reads take a JSON Pointer so only the part needed travels, and a change is a patch answered with the new revision — the document is never sent back. Every answer is compact JSON.

A board as files (optional)

Start with --bundle (or UBOARD_BUNDLE=1) and two more tools read and write the same board as files — for an assistant that edits an element's markup, style and script more than it moves parts. The board is still one stored document; the files are a way to read and write it.

| Tool | What it does | |---|---| | get_bundle | The board as files: board.json (parts, layout, states, skin — where an element's code or the background picture moved out it holds { "$file": path }), elements/<name>.html, .css, .js (a name that is not word characters and dashes is percent-encoded) and background.svg. Without files: the list with sizes and board.json; with files: the text of those. | | put_bundle | Saves the board from files, checked as any change is: files replace the files of the same path, edits ({ file, old, new }) change a file in place — old stands exactly once in it — so a long style is not sent again for a small change; the rest stays. An issue names the file it is in. |

License

AGPL-3.0-or-later, with a commercial license available — see the repository.