Update README.md

README.md

@@ -19,8 +19,16 @@ For each supported system, the flake exports:
 
 Current `default` points to the `t3code-desktop`.
 
+There are also `desktop` and `server` shorthands available for `apps` and `packages`.
+
 ## Usage
 
+Inspect the flake surface:
+
+```bash
+nix flake show --all-systems
+```
+
 Build the desktop package:
 
 ```bash
@@ -53,24 +61,26 @@ Both packages can be overridden to add AI agent CLIs to the runtime `PATH`:
 - `withClaudeCode` adds `github:numtide/llm-agents.nix#claude-code`
 - `withOpencode` adds `github:numtide/llm-agents.nix#opencode`
 
+Agent CLIs can be overridden as well using `codexPackage`, `claudeCodePackage` and `opencodePackage` respectively.
+
 These overrides wrap the finished package in a small `postBuild` layer, so changing the agent flags does not rebuild the full T3 Code package.
 
-In a Nix expression, use the same package override directly:
+In a Nix expression, use the same package override directly (using `perSystem` from [`github:numtide/blueprint`](https://github.com/numtide/blueprint)):
 
 ```nix
-self.packages.${system}.t3code-desktop.override {
+{perSystem, pkgs, ...}: {
+  home.packages = [
+    (perSystem.t3code.desktop.override {
       withCodex = true;
+      claudeCodePackage = pkgs.claude-code-bin;
       withClaudeCode = true;
+      opencodePackage = perSystem.foobar.my-awesome-opencode-fork;
       withOpencode = true;
+    })
+  ];
 }
 ```
 
-Inspect the flake surface:
-
-```bash
-nix flake show --all-systems
-```
-
 ## Layout
 
 ```text