Spelling Creator

Local setup (stdio) ​

For the ways a user connects, including the hosted connector, see Connect an AI assistant.

If a client supports remote MCP servers (claude.ai, Claude Desktop, Cursor and others), connecting to https://spellingcreator.org/mcp is simpler: add it, approve in the browser, done, with no token to manage. See Remote (hosted) mode. The steps below are for running the server yourself over stdio, for local development, a client that only supports local servers, or a self-hosted API (which doesn't serve /mcp).

1. Install ​

From the monorepo root:

bash
pnpm install

2. Sign in (get a token) ​

Publishing happens as a real hub user, so the server needs a Supabase session. The account also needs a display name (set it once in the web app's Settings) or publishing is rejected.

bash
pnpm --filter @spelling-creator/mcp login   # or, from the root: pnpm mcp:login

This emails a one-time code, verifies it, and saves a session to ~/.config/spelling-creator-mcp/session.json (or under $XDG_CONFIG_HOME, or wherever SPELLING_CREATOR_SESSION_FILE points), written with 0600 permissions. The server reads that file and auto-refreshes the short-lived access token, writing each rotated refresh token back, so it keeps working for weeks.

If the sign-in email shows only a magic link and no code, run pnpm --filter @spelling-creator/mcp login -- --paste instead and paste the whole value of the web app's sb-…-auth-token localStorage entry (DevTools, Application, Local Storage). The helper pulls access_token and refresh_token out of the JSON for you, including the base64- prefixed form Supabase sometimes stores.

Alternatively, skip the helper and provide a token through the environment: SUPABASE_REFRESH_TOKEN (long-lived, recommended) or SUPABASE_ACCESS_TOKEN (expires in about an hour). See Configuration for how these interact with the session file.

The server starts without any credentials. Tools that need the hub then fail with a message saying to sign in, while create_lesson_file and validate_lesson on sections (both entirely local) still work.

3. Connect your assistant ​

The server runs over stdio. Point the MCP client at apps/mcp/src/stdio.js.

Claude Desktop (claude_desktop_config.json):

json
{
  "mcpServers": {
    "spelling-creator": {
      "command": "node",
      "args": ["/absolute/path/to/spelling-creator/apps/mcp/src/stdio.js"]
    }
  }
}

Claude Code:

bash
claude mcp add spelling-creator -- node /absolute/path/to/spelling-creator/apps/mcp/src/stdio.js

Claude Code can also use the hosted server directly:

bash
claude mcp add --transport http spelling-creator https://spellingcreator.org/mcp

If you didn't use the login helper, pass the token in the client's env block, for example "env": { "SUPABASE_REFRESH_TOKEN": "..." }. To work against a local API (pnpm dev:api), also set SPELLING_CREATOR_API_URL=http://localhost:8787.

Then ask the assistant something like: "Make a lesson about domestic cats with a reading passage, a spelling list and some questions, and save it as a draft." If you hit a permission error, ask it to run whoami first.

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