npm for 9Router: packages, versions, and paths

npm is the package manager used to install 9Router’s published Node.js package. It downloads software and makes its command available; it does not supply model access, provider credits, or a running server by itself. If you already have Node and want the exact installation sequence, use npm install for 9Router.

Understand the three names

Node.js runs the JavaScript application. npm manages its packages. 9router is the published package and command you intend to install. Check them separately:

node --version
npm --version
npm view 9router name version repository.url engines

The last command reads registry metadata without installing the package. Compare the repository field with the upstream project. Do not choose a similarly named package because its search description sounds right. Package metadata helps establish identity, but it is not a security audit of the package contents.

Global and local installations serve different purposes

A global installation makes a command available through npm’s configured executable location. A local installation writes dependencies into the current project’s node_modules and updates its package metadata where appropriate. Running a bare npm install inside the 9Router source repository installs that project’s dependencies, not the globally published CLI.

Command	Meaning
npm view 9router version	Read the currently published version
npm list -g 9router --depth=0	Inspect the installed global package
npm prefix -g	Find the global installation prefix
npm install -g 9router	Install the published CLI globally
npm install inside a checkout	Install that checkout’s dependencies

Do not mix these workflows when diagnosing a problem. A terminal might run a global executable even while your current directory contains a newer source checkout.

Why can npm see the package while the shell cannot?

Package installation and command lookup are separate. Your shell must include the executable location in PATH. Node version managers can also give each runtime version its own global packages. After switching Node versions, the old installation may still exist but no longer be the one your shell uses.

On macOS or Linux, inspect command resolution with command -v node, command -v npm, and command -v 9router. On Windows, use where.exe node, where.exe npm, and where.exe 9router. Compare those paths with the runtime and prefix you intended to use. Reopen the terminal if an installer updated the environment after the shell started.

Handle permissions at the installation layer

For EACCES, npm documents using a Node version manager or a writable global directory. Avoid responding to every permission error by running an unreviewed install as administrator. First identify which directory is unwritable and why the current npm configuration uses it.

A package download error, registry timeout, permission error, and server port conflict require different repairs. Save the first meaningful error from npm instead of only the final “command failed” line. The npm install guide provides a practical symptom table.

Keep package updates separate from your data

The package directory contains application files. The router’s persistent data contains provider connections and settings. Confirm the data path for your installed version and back it up before upgrading. Do not assume deleting a global package backs up its data or that reinstalling it resets every setting.

Record the currently installed version before an update. Afterward, confirm the executable path, start the server, and repeat the same model-list and small-request checks. If you use a source checkout, record its commit separately. That makes a later issue report more useful than saying only “latest.”