---
title: "Overview"
description: "Learn what @bomb.sh/router is and when to use it"
canonical: https://bomb.sh/docs/router/basics/overview/
---

# Overview

`@bomb.sh/router` is a statically typed entry-point router for command-line applications. An argument parser tells you what the user typed. The router tells you where and how they intend to enter your program, and binds a validated, statically typed model for that entry point.

## Intents

The router matches input to an **intent**: a method at an application-relative route.

```text
HELP    /
VERSION /
EXECUTE /pr/list
HELP    /pr/create
EXECUTE /pr/create
```

There are three methods: `help`, `version`, and `execute`. Every route supports help. Version and execute exist only on the routes where you add them.

Every reachable intent appears in the result type of `parse()`. Narrow `method` and `route`, and TypeScript knows the exact model for that entry point:

```ts
import process from "node:process";
import {
  command,
  name,
  option,
  parse,
  route,
  schema,
} from "@bomb.sh/router";
import * as z from "zod";

const app = command(
  name("gh"),
  route(
    name("pr"),
    command(
      name("list"),
      option(name("limit"), schema(z.number().default(30))),
    ),
  ),
);

const result = parse(app, { argv: process.argv.slice(2) });

if (
  result.ok &&
  result.method === "execute" &&
  result.route === "/pr/list"
) {
  result.model.limit; // number
}
```

## What it is not

`@bomb.sh/router` is not a CLI framework. It does not own handlers, effects, output, or process lifetime. It is not a flag parser whose product is a bag of flags either. Its product is a typed intent, and your application decides what that intent does.

## Features

* **Typed intents:** `parse()` returns a discriminated union of every reachable entry point, so a `switch` on `method` and `route` is fully type-checked.
* **Route-scoped options:** Parent and child routes can declare the same option name without ambiguity, because each token binds to the route segment that owns it.
* **Multiple sources:** Bind CLI arguments, environment variables, and JavaScript values onto the same model, with an explicit precedence order.
* **Standard Schema validation:** Zod, ArkType, Valibot, and other [Standard Schema](https://standardschema.dev/) libraries work without adapters. Invalid data never reaches your application.
* **No I/O:** The parser is synchronous. It reads only the `argv`, values, and environment records you pass to it.
* **Runs everywhere:** No runtime-specific APIs, so it runs on Node.js, Deno, and Bun.

## Next steps

Head to [Installation](/docs/router/basics/installation/) to add `@bomb.sh/router` to your project.