Rails Blocks MCP
The Rails Blocks MCP server lets AI coding agents discover docs, inspect examples, and install components through the Rails Blocks CLI. It runs locally in your editor and keeps free component reads on the public static registry.
How it works
- 1. Your AI assistant asks: Cursor, Claude, or another MCP app asks Rails Blocks for help.
- 2. Rails Blocks runs locally: The MCP server runs on your computer with the
rails-blocksCLI. - 3. Free components are public: Free components come from the public Rails Blocks registry.
- 4. Pro components require a token: Pro components use your Rails Blocks access token.
Install
Install both the CLI and MCP package. The MCP server expects the rails-blocks executable to be available on your path.
gem install rails-blocks-cli
npm install -g @rails-blocks/mcpgem install rails-blocks-cli
yarn global add @rails-blocks/mcpConfigure your MCP client
Add the Rails Blocks MCP server to your client configuration. If your CLI executable is not on the default path, set RAILS_BLOCKS_CLI.
{
"mcpServers": {
"rails-blocks": {
"command": "rails-blocks-mcp",
"env": {
"RAILS_BLOCKS_CLI": "rails-blocks",
"RAILS_BLOCKS_API_TOKEN": "rb_your_pro_token"
}
}
}
}Available tools
rails_blocks_list_components- List all, free, or Pro components from the registry.
rails_blocks_search_docs- Find relevant components by name or keyword.
rails_blocks_get_docs- Fetch free or Pro docs, depending on token access.
rails_blocks_get_examples- Return usage examples for a component.
rails_blocks_install_component- Install a component. Agents should dry-run first unless you explicitly approve writes.
Authorize Pro access
Pro access is handled with access tokens. Run the CLI login once, approve the code in your browser or email, then your MCP server can use Pro docs and packages without sharing your password or browser session.
Sign in to authorize Pro access
The MCP server works with free public components without a token. Sign in with a Pro account to let MCP access Pro docs, examples, and installs.
rails-blocks login
rails-blocks login --email you@example.com
rails-blocks doctor
Prefer not to store a token in your MCP config? Use rails-blocks login once instead. The CLI stores the approved token locally in ~/.rails_blocks/config.json, and the MCP server reuses it.