Documentation for the plugin.msgpackz overhaul

Author: devyn

book/plugins.md

@@ -32,44 +32,39 @@ If you chose to download the git repository instead, run this when inside the cl
 > cargo install --path .
 ```
 
-This will create a binary file that can be used to register the plugin.
+This will create a binary file that can be used to add the plugin.
 
 Keep in mind that when installing using crates.io, the binary can be saved in different locations depending on how your system is set up. A typical location is in the users's home directory under .cargo/bin.
 
-## Registering a plugin
+## Adding a plugin
 
-To enable an installed plugin, call the [`register`](/commands/docs/register.md) command to tell Nu where to find it. As you do, you'll need to also tell Nushell what encoding the plugin uses.
+To add a plugin to the plugin cache file, call the [`plugin add`](/commands/docs/plugin_add.md) command to tell Nu where to find it.
 
 Please note that the plugin name needs to start with `nu_plugin_`, Nu uses the name prefix to detect plugins.
 
 Linux+macOS:
 
 ```nu
-> register ./my_plugins/nu_plugin_cool
+> plugin add ./my_plugins/nu_plugin_cool
 ```
 
 Windows:
 
 ```nu
-> register .\my_plugins\nu_plugin_cool.exe
+> plugin add .\my_plugins\nu_plugin_cool.exe
 ```
 
-When [`register`](/commands/docs/register.md) is called:
+When [`plugin add`](/commands/docs/plugin_add.md) is called, Nu runs the plugin binary and communicates via the [plugin protocol](plugin_protocol_reference.md) to get the signatures of all of the commands the plugin supports. It then saves information about the plugin, including the command signatures, to the plugin cache file at `$nu.plugin-path` in a custom brotli-compressed MessagePack format. This caching step saves `nu` from having to run all plugins during startup, which could be very slow.
 
-1. Nu launches the plugin, and waits for the plugin to tell Nu which communication encoding it should use
-2. Nu sends it a "Signature" message over stdin
-3. The plugin responds via stdout with a message containing its signature (name, description, arguments, flags, and more)
-4. Nu saves the plugin signature in the file at `$nu.plugin-path`, so registration is persisted across multiple launches
-
-Once registered, the plugin is available as part of your set of commands:
+Once added, the next time `nu` is started, the plugin's commands are available as part of your set of commands:
 
 ```nu
 > help commands | where command_type == "plugin"
 ```
 
 ### Updating a plugin
 
-When updating a plugin, it is important to run `register` again just as above to load the new signatures from the plugin and allow Nu to rewrite them to the plugin file (`$nu.plugin-path`).
+When updating a plugin, it is important to run `plugin add` again just as above to load the new signatures from the plugin and allow Nu to rewrite them to the plugin file (`$nu.plugin-path`).
 
 ## Managing plugins