Update README.md

README.md

@@ -45,6 +45,26 @@ Run the server app:
 nix run .#t3code-server
 ```
 
+## Agent CLI Support
+
+Both packages can be overridden to add AI agent CLIs to the runtime `PATH`:
+
+- `withCodex` adds `github:numtide/llm-agents.nix#codex`
+- `withClaudeCode` adds `github:numtide/llm-agents.nix#claude-code`
+- `withOpencode` adds `github:numtide/llm-agents.nix#opencode`
+
+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:
+
+```nix
+self.packages.${system}.t3code-desktop.override {
+  withCodex = true;
+  withClaudeCode = true;
+  withOpencode = true;
+}
+```
+
 Inspect the flake surface:
 
 ```bash
@@ -78,3 +98,4 @@ nix flake show --all-systems
 - `packages/t3code-desktop/build-nix-desktop-package.mjs` is local packaging glue carried by this repo.
 - `packages/t3code-desktop/desktop-nix-autoupdate.patch` is a downstream patch for desktop auto-update messaging in package-managed installs.
 - Upstream source is pinned in `flake.lock` via the `t3code` input.
+- Optional agent CLI packages are pinned in `flake.lock` via the `llm-agents` input.