diff --git a/config/claude/settings.json b/config/claude/settings.json
index 59a1820..830cb67 100644
--- a/config/claude/settings.json
+++ b/config/claude/settings.json
@@ -17,6 +17,16 @@
           }
         ]
       }
+    ],
+    "WorktreeCreate": [
+      {
+        "hooks": [
+          {
+            "type": "command",
+            "command": "~/.claude/hooks/worktree-create.sh"
+          }
+        ]
+      }
     ]
   },
   "statusLine": {
diff --git a/modules/claude.nix b/modules/claude.nix
index bb0bff6..77f5e40 100644
--- a/modules/claude.nix
+++ b/modules/claude.nix
@@ -17,6 +17,15 @@ let
     runtimeInputs = [ pkgs.jq ];
     text = builtins.readFile ./claude/block-dangerous-git.sh;
   };
+  worktreeCreate = pkgs.writeShellApplication {
+    name = "worktree-create";
+    runtimeInputs = [
+      pkgs.jq
+      pkgs.git
+      pkgs.coreutils
+    ];
+    text = builtins.readFile ./claude/worktree-create.sh;
+  };
 in
 {
   imports = [ ./agents.nix ];
@@ -32,4 +41,5 @@ in
   # Static scripts referenced by settings.json under stable ~/.claude paths.
   home.file.".claude/statusline-command.sh".source = lib.getExe statusline;
   home.file.".claude/hooks/block-dangerous-git.sh".source = lib.getExe blockDangerousGit;
+  home.file.".claude/hooks/worktree-create.sh".source = lib.getExe worktreeCreate;
 }
diff --git a/modules/claude/worktree-create.sh b/modules/claude/worktree-create.sh
new file mode 100644
index 0000000..fff84aa
--- /dev/null
+++ b/modules/claude/worktree-create.sh
@@ -0,0 +1,51 @@
+# Runs under writeShellApplication (set -euo pipefail). Claude Code's
+# WorktreeCreate hook: it fully replaces the default `git worktree add`, so this
+# script both places the worktree under ~/Code/worktrees/<repo>/<name> and copies
+# local, gitignored config into it. The created path MUST be the last stdout
+# line; all other output goes to stderr; any non-zero exit aborts creation.
+
+INPUT=$(cat)
+NAME=$(echo "$INPUT" | jq -r '.name')
+CWD=$(echo "$INPUT" | jq -r '.cwd')
+
+# The repo's primary working tree — our copy source and the basis for <repo> —
+# regardless of whether Claude runs from a linked worktree.
+COMMON_DIR=$(git -C "$CWD" rev-parse --path-format=absolute --git-common-dir)
+MAIN_ROOT=$(dirname "$COMMON_DIR")
+REPO=$(basename "$MAIN_ROOT")
+
+DEST="$HOME/Code/worktrees/$REPO/$NAME"
+
+# Base ref: origin's default branch (fresh). Fall back to HEAD if there's no origin.
+ORIGIN_HEAD=$(git -C "$MAIN_ROOT" symbolic-ref --quiet refs/remotes/origin/HEAD || true)
+if [ -z "$ORIGIN_HEAD" ]; then
+  git -C "$MAIN_ROOT" remote set-head origin --auto >&2 || true
+  ORIGIN_HEAD=$(git -C "$MAIN_ROOT" symbolic-ref --quiet refs/remotes/origin/HEAD || true)
+fi
+BASE_REF=${ORIGIN_HEAD#refs/remotes/}
+[ -z "$BASE_REF" ] && BASE_REF=HEAD
+
+mkdir -p "$(dirname "$DEST")"
+
+# New branch named after the slug; if it already exists, check it out instead.
+if git -C "$MAIN_ROOT" show-ref --verify --quiet "refs/heads/$NAME"; then
+  git -C "$MAIN_ROOT" worktree add "$DEST" "$NAME" >&2
+else
+  git -C "$MAIN_ROOT" worktree add -b "$NAME" "$DEST" "$BASE_REF" >&2
+fi
+
+# Carry uncommitted local config from the main checkout, if present.
+CARRY=(
+  devenv.nix devenv.yaml devenv.lock devenv.local.nix
+  .envrc .env .mcp.json
+  .claude/settings.json .claude/settings.local.json .claude/hooks
+)
+for item in "${CARRY[@]}"; do
+  src="$MAIN_ROOT/$item"
+  if [ -e "$src" ]; then
+    mkdir -p "$(dirname "$DEST/$item")"
+    cp -R "$src" "$DEST/$item" >&2
+  fi
+done
+
+echo "$DEST"