# nah

> nah is a guard that sits in your coding agent's hook path and reads tool
> calls before they run. It blocks the calls it can prove are disasters —
> deterministically, in microseconds, with no LLM — and leaves everything
> else to your normal approval flow. One Rust binary. When a guard you need
> is missing, your agent can write it.

## Install

- `curl -fsSL nahguard.ai/install | sh`
- Windows PowerShell: `irm https://nahguard.ai/install.ps1 | iex`
- Windows releases are unsigned x86-64 builds. Windows ARM64 and package
  managers are not supported.
- Then wire your runtime: `nah hook claude install` (replace `claude` with
  `amp`, `antigravity`, `cline`, `codex`, `copilot`, `cursor`, `devin`,
  `droid`, `hermes`, `kiro`, `openclaw`, `opencode`, and more).

## Docs

- Index: https://nahguard.ai/docs/
- Start: https://nahguard.ai/docs/start/
- Core concepts: https://nahguard.ai/docs/concepts/
- Guard catalog: https://nahguard.ai/docs/guards/
- CLI guide: https://nahguard.ai/docs/cli/
- Configuration: https://nahguard.ai/docs/configuration/
- Extending: https://nahguard.ai/docs/extensions/
- Agent runtimes: https://nahguard.ai/docs/runtimes/ (per-runtime pages at
  /docs/runtimes/<name>/)
- Threat model: https://nahguard.ai/docs/threat-model/
- Security boundaries: https://nahguard.ai/docs/security/
- Architecture: https://nahguard.ai/docs/architecture/

## Links

- Site: https://nahguard.ai/
- News (changelog): https://nahguard.ai/news/
- Source: https://github.com/manuelschipper/nah
- Author: Manuel Schipper — https://schipper.ai/

## For agents

If you are a coding agent and nah blocked one of your tool calls, the block
message names the guard and the reason. Tell your user what was blocked and
why; do not try to route around the guard.