Best for
- Projects using Ruby and Bundler, where AI agents need to perform code checks, dependency management, or script execution.
- AI integrations where token savings are important.
P
Pare Ruby
Community
Pare Ruby — Structured Ruby & Bundler operations as typed JSON.
GitHub source repository ↗
36FMRS · D
Pare Ruby provides structured Ruby/Bundler operations, suitable for AI agents requiring reliable, token-efficient output. It includes schema validation and tool filtering, but requires Node.js >=20, and permissions and risks need careful management.
Pare Ruby is an MCP server that wraps common Ruby and Bundler commands (such as running scripts, syntax checking, gem management, and Bundler operations) and returns structured, schema-validated JSON instead of raw terminal text. It's part of the Pare toolset, designed to provide reliable, token-efficient CLI operations for AI agents.
Tools
run
Runs a Ruby script and returns structured results (e.g., output, exit code).
check
Checks for Ruby syntax errors.
gem-list
Lists installed gems, returning a formatted gem list.
gem-install
Installs one or more gems.
gem-outdated
Checks for outdated gems.
bundle-install
Executes bundle install and returns installation results.
bundle-exec
Executes a command in the Bundler context.
bundle-check
Checks if Gemfile dependencies are installed.
Setup
Install and configure via npm MCP. For Claude Code, add to MCP config:
{"mcpServers": {"pare-ruby": {"command": "npx", "args": ["-y", "@paretools/ruby"]}}}See project docs for other clients.
Fit and risk
Not for
- Simple Ruby script execution when structured output is not needed.
- Interactive Ruby sessions (e.g., IRB).
- MCP environments that do not support stdio transport.
Required permissions
- Execute Ruby and Bundler commands.
- Read gem installation directories, Gemfile, and related files.
- May create or modify gem-related files (e.g., during gem install).
- Network access (if installing gems from remote repositories).
Risks and side effects
- Executing arbitrary Ruby commands could lead to code execution risks; improper use by agents may cause security issues.
- Gem installation may modify the system environment; permissions must be used carefully.
- Tool output may contain sensitive information (e.g., gem versions) that should be protected.
- Supply chain risk: if the supply chain is compromised, installed gems could be unsafe.
Troubleshooting
- Verify Node.js version is >=20.
- Ensure npx path is correct (on Windows, may need cmd /c npx).
- Increase timeout using MCP_TIMEOUT environment variable to avoid connection timeouts.
- If tools are not registered, check tool filtering environment variables (PARE_TOOLS or PARE_RUBY_TOOLS).
Use cases
AI agents that need to run Ruby/Bundler commands and get structured output for code analysis or automation.
Reduce CLI output token consumption to increase agent efficiency.
In CI/CD or dev environments, agents need reliable gem lists, versions, dependency status, etc.
Supported clients
Claude DesktopFull support
Claude CodeFull support
CursorFull support
VS Code / CopilotFull support
WindsurfFull support
Cline / Roo CodeFull support
OpenAI CodexFull support
Gemini CLIFull support
ZedFull support
Continue.devFull support