# @opensip-cli/fitness > Fitness checks engine for OpenSIP CLI This package is the **engine** behind a first-party `opensip-cli` tool. The CLI bundles it — you do not normally install it directly. Part of [**opensip-cli**](https://github.com/opensip-ai/opensip-cli) — an open-source codebase intelligence CLI: fitness checks (`fit`), static call-graph analysis (`graph`), simulation (`sim`), and advisory reduction audits (`yagni`). **Distribution model:** the published `opensip-cli` npm package is a full-stack bundle of first-party tools, check packs, and language adapters. Third-party tools install separately via the `opensipTools` manifest and host allowlist; a slim install without bundled tools is not a current goal. ## Install Most users install the CLI, which bundles the first-party tools: ```bash curl -fsSL https://opensip.ai/cli/install.sh | bash ``` This package is published for the CLI and advanced plugin authors; most users should not install `@opensip-cli/fitness` directly. ## Documentation - 📚 Project docs: https://opensip.ai/docs/opensip-cli/ - 🧭 Package catalog (what every package does): https://github.com/opensip-ai/opensip-cli/blob/v0.8.5/docs/public/70-reference/02-package-catalog.md - 📦 Source: https://github.com/opensip-ai/opensip-cli/tree/v0.8.5/packages/fitness/engine ## License Apache-2.0 © opensip-ai