diff --git a/.claude/tasks/0001-toolkit-bundle.md b/.claude/tasks/0001-toolkit-bundle.md
new file mode 100644
index 0000000..d133997
--- /dev/null
+++ b/.claude/tasks/0001-toolkit-bundle.md
@@ -0,0 +1,23 @@
+---
+spec: guests
+---
+
+## What to build
+
+A new bundle Module, `modules.toolkit`, that turns on the baseline interactive environment — fish, tmux, nvim, git, and direnv — as one unit.
+Enabling it on a Host brings up all five together, so any Host or Guest shell feels identical.
+This is a deliberate bundle wanted as a unit, distinct from the grouping-directory aggregate enables ADR 0004 rejected.
+
+## Acceptance criteria
+
+- [x] `modules.toolkit` declares an `enable` option following the Enable convention and lives at a path its file location mirrors, per the Namespace convention.
+- [x] Enabling `modules.toolkit` turns on fish, tmux, nvim, git, and direnv as a group.
+- [x] A Host that enables `modules.toolkit` still reads as a flat checklist — the bundle is one line, not a hidden group of five.
+- [x] A Host enabling `modules.toolkit` builds via `nix flake check`, and the five underlying Modules are enabled (verifiable by `nix eval` of their `enable` values).
+
+## Implementation Notes
+
+- `modules/toolkit.nix` follows the sanctioned aggregator pattern of `modules/desktop/desktop.nix`: an index node whose `enable` sets each member's `enable = lib.mkDefault true`, so a Host can still override any single piece while the one flag brings up the bundle.
+- `neogaia` was converted as the demonstrating Host: its five individual `modules.{fish,git,direnv,tmux,nvim}.enable = true` lines collapse to one `modules.toolkit.enable = true`. The host-specific `modules.fish.defaultShell = true` stays, since it is placement beyond the bundle's baseline enable.
+- Verified: `nix flake check` builds `checks.x86_64-linux.neogaia`, and `nix eval` of each of the five members' `enable` on neogaia returns `true`.
+- The working tree also carries `.claude/CONTEXT.md`, ADR 0006, and the `guests` spec — planning artifacts for the wider `guests` spec, not this task. They are deliberately left out of this task's commit and staged separately by the broader work.
diff --git a/hosts/neogaia/default.nix b/hosts/neogaia/default.nix
index d7cc9c4..8012559 100644
--- a/hosts/neogaia/default.nix
+++ b/hosts/neogaia/default.nix
@@ -42,14 +42,10 @@
   # A machine the operator works from, so it admits the workstation keys alone.
   modules.ssh.authorizedKeys = config.modules.ssh.workstationKeys;
 
+  modules.toolkit.enable = true;
   # fish as the login shell.
-  modules.fish.enable = true;
   modules.fish.defaultShell = true;
 
-  modules.git.enable = true;
-  modules.direnv.enable = true;
-  modules.tmux.enable = true;
-  modules.nvim.enable = true;
   modules.agents.claude-code.enable = true;
   modules.agents.tools.gitea-axi.enable = true;
   modules.agents.pi.enable = true;
diff --git a/modules/toolkit.nix b/modules/toolkit.nix
new file mode 100644
index 0000000..814fcdf
--- /dev/null
+++ b/modules/toolkit.nix
@@ -0,0 +1,18 @@
+{ config, lib, ... }:
+# The baseline interactive toolset as one deliberate bundle.
+let
+  cfg = config.modules.toolkit;
+in
+{
+  options.modules.toolkit.enable =
+    lib.mkEnableOption "the baseline interactive environment — fish, tmux, nvim, git, and direnv — as one unit";
+
+  # Each piece is turned on at default priority, so a host can still override any one of them.
+  config = lib.mkIf cfg.enable {
+    modules.fish.enable = lib.mkDefault true;
+    modules.tmux.enable = lib.mkDefault true;
+    modules.nvim.enable = lib.mkDefault true;
+    modules.git.enable = lib.mkDefault true;
+    modules.direnv.enable = lib.mkDefault true;
+  };
+}