diff --git a/bin/wt-add b/bin/wt-add
index 445a19f..84d5d60 100755
--- a/bin/wt-add
+++ b/bin/wt-add
@@ -79,6 +79,9 @@ else
 fi
 wt_require_valid_config || exit 1
 
+# Source wt-adopt library for adoption treatment
+wt_source wt-adopt
+
 usage() {
   echo "Usage: $(basename "$0") [git worktree add arguments...]"
   echo
@@ -140,81 +143,6 @@ while [[ $i -lt ${#ARGS[@]} ]]; do
   i=$((i + 1))
 done
 
-# Helper: install project metadata for a created worktree
-install_metadata_for_worktree() {
-  local worktree_path="$1"
-
-  # Normalize to absolute (worktree now exists)
-  local worktree_path_abs
-  worktree_path_abs="$(cd "$worktree_path" && pwd)"
-
-  echo "Installing project metadata into worktree: $worktree_path_abs"
-
-  # Find wt-metadata-import: try script directory first, then PATH
-  local metadata_import=""
-  if [[ -f "$SCRIPT_DIR/wt-metadata-import" ]]; then
-    metadata_import="$SCRIPT_DIR/wt-metadata-import"
-  elif command -v wt-metadata-import >/dev/null 2>&1; then
-    metadata_import="wt-metadata-import"
-  else
-    error "Cannot find wt-metadata-import"
-    return 1
-  fi
-
-  "$metadata_import" -y "$WT_IDEA_FILES_BASE" "$worktree_path_abs"
-}
-
-# Helper: install Bazel output symlinks (bazel-out, bazel-bin, etc.) for a created worktree
-#
-# Bazel stores build outputs in a central cache directory (typically under /private/var/tmp).
-# The symlinks (bazel-out, bazel-bin, etc.) in the repo root point to this shared cache.
-# By copying these symlinks to new worktrees, we enable:
-#   1. Faster IntelliJ/IDE sync (no rebuild required)
-#   2. Shared build cache across worktrees
-#   3. Immediate access to compiled artifacts
-install_bazel_symlinks_for_worktree() {
-  local worktree_path="$1"
-
-  # Normalize to absolute (worktree now exists)
-  local worktree_path_abs
-  worktree_path_abs="$(cd "$worktree_path" && pwd)"
-
-  # List of Bazel symlinks to copy from main repo
-  # These are the most important ones for IntelliJ sync performance
-  local bazel_symlinks=("bazel-out" "bazel-bin" "bazel-testlogs" "bazel-genfiles")
-  
-  local main_repo_abs
-  main_repo_abs="$(cd "$WT_MAIN_REPO_ROOT" && pwd)"
-
-  echo "Installing Bazel symlinks into worktree: $worktree_path_abs"
-
-  for symlink_name in "${bazel_symlinks[@]}"; do
-    local src_link="$main_repo_abs/$symlink_name"
-    local dst_link="$worktree_path_abs/$symlink_name"
-
-    # Check if source symlink exists in main repo
-    if [[ -L "$src_link" ]]; then
-      # Get the target of the symlink
-      local target
-      target="$(readlink "$src_link")"
-
-      # If the target is relative, make it absolute based on main repo location
-      if [[ "$target" != /* ]]; then
-        target="$main_repo_abs/$target"
-      fi
-
-      # Remove existing symlink/file in worktree if present
-      if [[ -L "$dst_link" || -e "$dst_link" ]]; then
-        rm -rf "$dst_link"
-      fi
-
-      # Create symlink pointing to the same target
-      ln -s "$target" "$dst_link"
-      echo "  ✓ $symlink_name -> $target"
-    fi
-  done
-}
-
 ########################################
 # Fast path: NOT creating a new branch #
 ########################################
@@ -266,8 +194,7 @@ if [[ $creating_new_branch -eq 0 ]]; then
     echo "Creating worktree for existing branch '$local_branch' at: $worktree_path"
     git worktree add -- "$worktree_path" "$local_branch"
 
-    install_metadata_for_worktree "$worktree_path"
-    install_bazel_symlinks_for_worktree "$worktree_path"
+    wt_adopt_worktree --force "$(cd "$worktree_path" && pwd -P)"
     success "git worktree add completed successfully."
     exit 0
   fi
@@ -288,8 +215,7 @@ if [[ $creating_new_branch -eq 0 ]]; then
   info "Not creating a new branch; running: git worktree add ${ARGS[*]}"
   git worktree add "${ARGS[@]}"
 
-  install_metadata_for_worktree "$worktree_path"
-  install_bazel_symlinks_for_worktree "$worktree_path"
+  wt_adopt_worktree --force "$(cd "$worktree_path" && pwd -P)"
   success "git worktree add completed successfully."
   exit 0
 fi
@@ -475,8 +401,7 @@ else
   git worktree add "${FINAL_ARGS[@]}"
 fi
 
-install_metadata_for_worktree "$worktree_path"
-install_bazel_symlinks_for_worktree "$worktree_path"
+wt_adopt_worktree --force "$(cd "$worktree_path" && pwd -P)"
 
 success "git worktree add completed successfully."
 exit 0
diff --git a/bin/wt-adopt b/bin/wt-adopt
new file mode 100755
index 0000000..23b0999
--- /dev/null
+++ b/bin/wt-adopt
@@ -0,0 +1,144 @@
+#!/usr/bin/env bash
+#
+# wt-adopt — Adopt an existing worktree into wt management
+# ==========================================================
+#
+# Takes any existing git worktree and gives it the "wt treatment":
+# imports metadata from the vault, installs Bazel symlinks, and places
+# a marker file so wt commands recognize it as managed.
+#
+# Usage:
+#   wt-adopt                    # Adopt the worktree at CWD
+#   wt-adopt <worktree-path>    # Adopt the specified worktree
+#   wt-adopt <branch-name>      # Adopt the worktree for the given branch
+#   wt-adopt --redo             # Re-run adoption treatment on current worktree
+#   wt-adopt --force            # Skip conflict checks, overwrite without prompting
+#
+# Notes:
+#   - The main repository cannot be adopted (only worktrees).
+#   - Re-adopting an already-adopted worktree requires --redo or --force.
+#   - If the worktree has existing metadata, interactive sessions prompt
+#     with overwrite/keep/abort; non-interactive sessions abort.
+#
+
+set -euo pipefail
+
+# Resolve script and lib directories
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+LIB_DIR="$SCRIPT_DIR/../lib"
+
+# Bootstrap: source wt-common from lib/
+if [[ -f "$LIB_DIR/wt-common" ]]; then
+  . "$LIB_DIR/wt-common"
+elif [[ -f "$HOME/.wt/lib/wt-common" ]]; then
+  . "$HOME/.wt/lib/wt-common"
+else
+  echo "Error: Cannot find wt-common" >&2
+  exit 1
+fi
+wt_require_valid_config || exit 1
+
+# Source wt-adopt library
+wt_source wt-adopt
+
+usage() {
+  cat <<EOF
+Usage: $(basename "$0") [options] [worktree-path|branch-name]
+
+Adopt an existing worktree into wt management.
+
+Options:
+  --force       Skip conflict checks (overwrite without prompting)
+  --redo        Re-run adoption treatment on already-adopted worktree
+  -h, --help    Show this help
+
+Modes:
+  $(basename "$0")                          # Adopt worktree at current directory
+  $(basename "$0") <worktree-path|branch>   # Adopt specified worktree
+  $(basename "$0") --redo                   # Re-adopt current worktree
+  $(basename "$0") --redo --force           # Re-adopt, overwrite without prompting
+EOF
+}
+
+TARGET_WORKTREE=""
+FORCE=false
+REDO=false
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    --force)
+      FORCE=true
+      shift
+      ;;
+    --redo)
+      REDO=true
+      shift
+      ;;
+    -*)
+      error "Unknown option: $1"
+      usage >&2
+      exit 1
+      ;;
+    *)
+      if [[ -n "$TARGET_WORKTREE" ]]; then
+        error "Too many arguments"
+        usage >&2
+        exit 1
+      fi
+      TARGET_WORKTREE="$1"
+      shift
+      ;;
+  esac
+done
+
+# Show context banner if contexts are configured
+wt_show_context_banner
+
+# Resolve target worktree
+if [[ -z "$TARGET_WORKTREE" ]]; then
+  # Resolve to worktree root, not CWD (user may be in a subdirectory)
+  TARGET_WORKTREE="$(git rev-parse --show-toplevel 2>/dev/null)" || {
+    error "Not inside a git repository"
+    exit 1
+  }
+else
+  TARGET_WORKTREE="$(wt_resolve_and_validate "$TARGET_WORKTREE")" || exit 1
+fi
+
+# Validate it's a git worktree or repo
+if ! git -C "$TARGET_WORKTREE" rev-parse --is-inside-work-tree >/dev/null 2>&1; then
+  error "Not a git repository or worktree: $TARGET_WORKTREE"
+  exit 1
+fi
+
+# Block adoption of the main repo
+if wt_is_main_repo "$TARGET_WORKTREE"; then
+  error "Cannot adopt the main repository. Only worktrees can be adopted."
+  exit 1
+fi
+
+# Build args for wt_adopt_worktree
+adopt_args=()
+if [[ "$FORCE" == true ]]; then
+  adopt_args+=("--force")
+fi
+adopt_args+=("$TARGET_WORKTREE")
+
+# Check if already adopted
+if wt_is_adopted "$TARGET_WORKTREE"; then
+  if [[ "$REDO" == true || "$FORCE" == true ]]; then
+    info "Re-running adoption treatment: $TARGET_WORKTREE"
+    wt_adopt_worktree "${adopt_args[@]}"
+  else
+    info "Worktree is already adopted: $TARGET_WORKTREE"
+    info "Use --redo to re-run adoption treatment, or --force to force."
+  fi
+  exit 0
+fi
+
+# Run adoption
+wt_adopt_worktree "${adopt_args[@]}"
diff --git a/completion/wt.bash b/completion/wt.bash
index b05fa61..ac0c4c1 100644
--- a/completion/wt.bash
+++ b/completion/wt.bash
@@ -299,6 +299,7 @@ _wt_metadata_import_complete() {
 
 # --- Wire up standalone wt-* completions (only if commands exist on PATH) ---
 type wt-add >/dev/null 2>&1 && complete -F _wt_add_complete wt-add
+type wt-adopt >/dev/null 2>&1 && complete -F _wt_switch_complete wt-adopt
 type wt-switch >/dev/null 2>&1 && complete -F _wt_switch_complete wt-switch
 type wt-remove >/dev/null 2>&1 && complete -F _wt_remove_complete wt-remove
 type wt-cd >/dev/null 2>&1 && complete -F _wt_cd_complete wt-cd
@@ -318,7 +319,7 @@ _wt_completion_bash() {
   cur="${COMP_WORDS[COMP_CWORD]}"
 
   if [[ ${COMP_CWORD} -eq 1 ]]; then
-    local commands="add switch remove list cd context metadata-export metadata-import ijwb-export ijwb-import help"
+    local commands="add adopt switch remove list cd context metadata-export metadata-import ijwb-export ijwb-import help"
     COMPREPLY=($(compgen -W "$commands" -- "$cur"))
   else
     case "${COMP_WORDS[1]}" in
@@ -327,6 +328,14 @@ _wt_completion_bash() {
         branches=$(git branch -a 2>/dev/null | sed 's/^[* ]*//' | sed 's|remotes/origin/||')
         COMPREPLY=($(compgen -W "$branches" -- "$cur"))
         ;;
+      adopt)
+        local branches
+        branches="$(wt_worktree_branch_list)"
+        if [[ -n "$branches" ]]; then
+          local IFS=$'\n'
+          COMPREPLY+=($(compgen -W "$branches" -- "$cur"))
+        fi
+        ;;
       switch|cd)
         local branches
         branches="$(wt_worktree_branch_list)"
diff --git a/completion/wt.zsh b/completion/wt.zsh
index 63f1ac3..b8288c7 100644
--- a/completion/wt.zsh
+++ b/completion/wt.zsh
@@ -294,6 +294,7 @@ fi
 # Register standalone wt-* completions
 # ═══════════════════════════════════════════════════════════════════════════════
 
+compdef _wt_switch wt-adopt
 compdef _wt_switch wt-switch
 compdef _wt_remove wt-remove
 compdef _wt_cd wt-cd
@@ -312,6 +313,7 @@ _wt_completion() {
   local -a commands
   commands=(
     'add:Create a new worktree for a branch'
+    'adopt:Adopt an existing worktree into wt management'
     'switch:Switch the active worktree symlink'
     'remove:Remove a worktree'
     'list:List all worktrees with status'
@@ -343,6 +345,7 @@ _wt_completion() {
           branches=("${(f)$(git branch -a 2>/dev/null | sed 's/^[* ]*//' | sed 's|remotes/origin/||')}")
           (( ${#branches[@]} > 0 )) && _describe 'branch' branches
           ;;
+        adopt)                  _wt_switch ;;
         switch|cd)              _wt_switch ;;
         remove)                 _wt_remove ;;
         context)                _wt_context ;;
diff --git a/lib/wt-adopt b/lib/wt-adopt
new file mode 100644
index 0000000..cb12fc2
--- /dev/null
+++ b/lib/wt-adopt
@@ -0,0 +1,302 @@
+#!/usr/bin/env bash
+#
+# wt-adopt — Adoption helpers for worktree management
+# ====================================================
+#
+# Provides functions for adopting existing worktrees into wt management.
+# "Adopting" means: importing metadata, installing Bazel symlinks, and
+# placing a marker file so wt knows this worktree is managed.
+#
+# Marker file location:
+#   $(git rev-parse --git-dir)/wt/adopted
+#
+# This resolves to:
+#   - .git/worktrees/<name>/wt/adopted  (for worktrees)
+#   - .git/wt/adopted                    (for the main repo — but adoption is blocked)
+#
+
+# ─────────────────────────────────────────────────────────────────────────────
+# Marker file helpers
+# ─────────────────────────────────────────────────────────────────────────────
+
+# Check if a worktree has been adopted by wt.
+# Args: $1 = worktree path (default: CWD)
+# Returns: 0 if adopted, 1 if not
+wt_is_adopted() {
+  local worktree_path="${1:-.}"
+  local git_dir
+  git_dir="$(git -C "$worktree_path" rev-parse --git-dir 2>/dev/null)" || return 1
+
+  # Resolve to absolute path
+  if [[ "$git_dir" != /* ]]; then
+    git_dir="$(cd "$worktree_path" && cd "$git_dir" && pwd -P)"
+  fi
+
+  [[ -f "$git_dir/wt/adopted" ]]
+}
+
+# Mark a worktree as adopted.
+# Args: $1 = worktree path (default: CWD)
+# Returns: 0 on success, 1 on failure
+wt_mark_adopted() {
+  local worktree_path="${1:-.}"
+  local git_dir
+  git_dir="$(git -C "$worktree_path" rev-parse --git-dir 2>/dev/null)" || return 1
+
+  if [[ "$git_dir" != /* ]]; then
+    git_dir="$(cd "$worktree_path" && cd "$git_dir" && pwd -P)"
+  fi
+
+  mkdir -p "$git_dir/wt"
+  touch "$git_dir/wt/adopted"
+}
+
+# Remove adoption marker from a worktree.
+# Args: $1 = worktree path (default: CWD)
+# Returns: 0 on success, 1 on failure
+wt_unmark_adopted() {
+  local worktree_path="${1:-.}"
+  local git_dir
+  git_dir="$(git -C "$worktree_path" rev-parse --git-dir 2>/dev/null)" || return 1
+
+  if [[ "$git_dir" != /* ]]; then
+    git_dir="$(cd "$worktree_path" && cd "$git_dir" && pwd -P)"
+  fi
+
+  rm -f "$git_dir/wt/adopted"
+  rmdir "$git_dir/wt" 2>/dev/null || true
+}
+
+# Check if a path is the main repository (not a worktree).
+# In the main repo, git-dir and git-common-dir resolve to the same place.
+# In a worktree, git-dir is .git/worktrees/<name>, common-dir is .git.
+# Args: $1 = path (default: CWD)
+# Returns: 0 if main repo, 1 if worktree or not a git repo
+wt_is_main_repo() {
+  local path="${1:-.}"
+  local git_dir common_dir
+  git_dir="$(git -C "$path" rev-parse --git-dir 2>/dev/null)" || return 1
+  common_dir="$(git -C "$path" rev-parse --git-common-dir 2>/dev/null)" || return 1
+
+  # Resolve both to absolute physical paths for comparison
+  local abs_git_dir abs_common_dir
+  abs_git_dir="$(cd "$path" && cd "$git_dir" && pwd -P)"
+  abs_common_dir="$(cd "$path" && cd "$common_dir" && pwd -P)"
+
+  [[ "$abs_git_dir" == "$abs_common_dir" ]]
+}
+
+# ─────────────────────────────────────────────────────────────────────────────
+# Helpers
+# ─────────────────────────────────────────────────────────────────────────────
+
+# Check if the current session is interactive (stdin and stderr are TTYs).
+# Extracted as a function so tests can override it.
+_wt_is_interactive() { [[ -t 0 && -t 2 ]]; }
+
+# ─────────────────────────────────────────────────────────────────────────────
+# Conflict detection
+# ─────────────────────────────────────────────────────────────────────────────
+
+# Check for existing files in a worktree that would be overwritten by adoption.
+#
+# Scans:
+#   - The vault (WT_IDEA_FILES_BASE) for metadata matching WT_METADATA_PATTERNS,
+#     then checks if the corresponding target paths exist in the worktree.
+#     This mirrors the same vault-scanning logic used by wt-metadata-import.
+#   - Bazel output directories that are real directories (not symlinks —
+#     symlinks are always safe to replace)
+#
+# Args: $1 = worktree path (absolute)
+# Outputs: conflicting relative paths to stdout (one per line)
+# Returns: 0 if conflicts found, 1 if no conflicts
+wt_check_adoption_conflicts() {
+  local worktree_path="$1"
+  local -a conflicts=()
+  local vault="${WT_IDEA_FILES_BASE:-}"
+
+  # Check metadata patterns by scanning the vault (same as wt-metadata-import)
+  if [[ -n "$vault" && -d "$vault" ]]; then
+    for pattern in ${WT_METADATA_PATTERNS:-}; do
+      while IFS= read -r -d '' meta_src; do
+        # Compute relative path from vault root (mirrors import_pattern logic)
+        local parent_src
+        parent_src="$(dirname "$meta_src")"
+        local rel_path=""
+        if [[ "$parent_src" != "$vault" ]]; then
+          rel_path="${parent_src#"$vault"/}"
+        fi
+
+        # Map to corresponding target in worktree
+        local target_meta
+        if [[ -z "$rel_path" ]]; then
+          target_meta="$worktree_path/$pattern"
+        else
+          target_meta="$worktree_path/$rel_path/$pattern"
+        fi
+
+        # Check if target already exists
+        if [[ -e "$target_meta" || -L "$target_meta" ]]; then
+          if [[ -z "$rel_path" ]]; then
+            conflicts+=("$pattern")
+          else
+            conflicts+=("$rel_path/$pattern")
+          fi
+        fi
+      done < <(find -L "$vault" \( -type l -o -type d \) -name "$pattern" -print0 2>/dev/null)
+    done
+  fi
+
+  # Check Bazel dirs (only real dirs, not symlinks)
+  local -a bazel_names=("bazel-out" "bazel-bin" "bazel-testlogs" "bazel-genfiles")
+  for name in "${bazel_names[@]}"; do
+    local target="$worktree_path/$name"
+    if [[ -d "$target" && ! -L "$target" ]]; then
+      conflicts+=("$name (real directory)")
+    fi
+  done
+
+  if [[ ${#conflicts[@]} -eq 0 ]]; then
+    return 1
+  fi
+
+  printf '%s\n' "${conflicts[@]}"
+  return 0
+}
+
+# ─────────────────────────────────────────────────────────────────────────────
+# Treatment functions
+# ─────────────────────────────────────────────────────────────────────────────
+
+# Install Bazel output symlinks into a worktree.
+# Copies bazel-out, bazel-bin, etc. from the main repo so the worktree
+# shares the build cache (faster IDE sync, no rebuild needed).
+# Args: $1 = worktree path (absolute)
+wt_install_bazel_symlinks() {
+  local worktree_path="$1"
+
+  local bazel_symlinks=("bazel-out" "bazel-bin" "bazel-testlogs" "bazel-genfiles")
+
+  local main_repo_abs
+  main_repo_abs="$(cd "$WT_MAIN_REPO_ROOT" && pwd)"
+
+  info "Installing Bazel symlinks into worktree: $worktree_path"
+
+  for symlink_name in "${bazel_symlinks[@]}"; do
+    local src_link="$main_repo_abs/$symlink_name"
+    local dst_link="$worktree_path/$symlink_name"
+
+    if [[ -L "$src_link" ]]; then
+      local target
+      target="$(readlink "$src_link")"
+
+      if [[ "$target" != /* ]]; then
+        target="$main_repo_abs/$target"
+      fi
+
+      if [[ -L "$dst_link" || -e "$dst_link" ]]; then
+        rm -rf "$dst_link"
+      fi
+
+      ln -s "$target" "$dst_link"
+      info "  $symlink_name -> $target"
+    fi
+  done
+}
+
+# Run the full adoption treatment on a worktree.
+# 1. Check for conflicting files (unless --force)
+# 2. Import metadata from vault (unless keep_existing)
+# 3. Install Bazel symlinks (always)
+# 4. Place adoption marker
+#
+# Args: [--force] <worktree_path>
+#   --force: skip conflict check (used by wt-add for fresh worktrees)
+# Requires: WT_IDEA_FILES_BASE to be set
+# Returns: 0 on success, 1 if aborted due to conflicts
+wt_adopt_worktree() {
+  local worktree_path=""
+  local force=false
+
+  while [[ $# -gt 0 ]]; do
+    case "$1" in
+      --force) force=true ;;
+      *) worktree_path="$1" ;;
+    esac
+    shift
+  done
+
+  local keep_existing=false
+
+  # 1. Conflict check
+  if [[ "$force" != true ]]; then
+    local conflict_list
+    if conflict_list="$(wt_check_adoption_conflicts "$worktree_path")"; then
+      warn "The following files in the worktree will be overwritten by adoption:"
+      while IFS= read -r item; do
+        echo "  - $item" >&2
+      done <<< "$conflict_list"
+      echo >&2
+
+      if _wt_is_interactive; then
+        echo "  [O]verwrite — replace with vault contents" >&2
+        echo "  [K]eep     — adopt without importing metadata (Bazel symlinks still installed)" >&2
+        echo "  [A]bort    — cancel adoption" >&2
+        echo >&2
+
+        local response
+        if ! read -erp "Choose [O/K/A]: " response; then
+          echo >&2
+          return 1
+        fi
+
+        case "$response" in
+          [oO]|[oO][vV]*)
+            # Overwrite — proceed with full treatment
+            ;;
+          [kK]|[kK][eE]*)
+            # Keep — skip metadata import
+            keep_existing=true
+            ;;
+          *)
+            echo "Aborted." >&2
+            return 1
+            ;;
+        esac
+      else
+        error "Aborting: worktree has existing files that would be overwritten (use --force to override)"
+        return 1
+      fi
+    fi
+  fi
+
+  # 2. Import metadata (unless keeping existing files)
+  if [[ "$keep_existing" != true ]]; then
+    local metadata_import=""
+    if [[ -n "${SCRIPT_DIR:-}" && -x "$SCRIPT_DIR/wt-metadata-import" ]]; then
+      metadata_import="$SCRIPT_DIR/wt-metadata-import"
+    elif [[ -x "$HOME/.wt/bin/wt-metadata-import" ]]; then
+      metadata_import="$HOME/.wt/bin/wt-metadata-import"
+    elif command -v wt-metadata-import >/dev/null 2>&1; then
+      metadata_import="wt-metadata-import"
+    fi
+
+    if [[ -n "$metadata_import" && -d "${WT_IDEA_FILES_BASE:-}" ]]; then
+      info "Importing metadata into worktree: $worktree_path"
+      if ! "$metadata_import" -y "$WT_IDEA_FILES_BASE" "$worktree_path"; then
+        error "Metadata import failed — worktree not adopted"
+        return 1
+      fi
+    fi
+  else
+    info "Keeping existing metadata files"
+  fi
+
+  # 3. Install Bazel symlinks (always — even with keep_existing)
+  wt_install_bazel_symlinks "$worktree_path"
+
+  # 4. Mark as adopted
+  wt_mark_adopted "$worktree_path"
+
+  success "Worktree adopted: $worktree_path"
+}
diff --git a/test/integration/wt-add.bats b/test/integration/wt-add.bats
index 5c24de4..e8aee42 100644
--- a/test/integration/wt-add.bats
+++ b/test/integration/wt-add.bats
@@ -32,6 +32,7 @@ teardown() {
     run "$TEST_HOME/.wt/bin/wt-add" existing-branch
     assert_success
     assert_is_worktree "$WT_WORKTREES_BASE/existing-branch"
+    assert_is_adopted "$WT_WORKTREES_BASE/existing-branch"
     local branch=$(cd "$WT_WORKTREES_BASE/existing-branch" && git branch --show-current)
     assert_equal "$branch" "existing-branch"
 }
@@ -43,6 +44,7 @@ teardown() {
     run "$TEST_HOME/.wt/bin/wt-add" "$custom_path" feature-path
     assert_success
     assert_is_worktree "$custom_path"
+    assert_is_adopted "$custom_path"
     local branch=$(cd "$custom_path" && git branch --show-current)
     assert_equal "$branch" "feature-path"
 }
@@ -55,6 +57,7 @@ teardown() {
     run "$TEST_HOME/.wt/bin/wt-add" -b new-feature
     assert_success
     assert_is_worktree "$WT_WORKTREES_BASE/new-feature"
+    assert_is_adopted "$WT_WORKTREES_BASE/new-feature"
     local branch=$(cd "$WT_WORKTREES_BASE/new-feature" && git branch --show-current)
     assert_equal "$branch" "new-feature"
 }
diff --git a/test/integration/wt-adopt.bats b/test/integration/wt-adopt.bats
new file mode 100644
index 0000000..5909605
--- /dev/null
+++ b/test/integration/wt-adopt.bats
@@ -0,0 +1,420 @@
+#!/usr/bin/env bats
+
+# Integration tests for bin/wt-adopt
+
+setup() {
+    load '../test_helper/common'
+    setup_test_env
+
+    REPO=$(create_mock_repo_with_remote "$BATS_TEST_TMPDIR/repo")
+    create_test_context "test" "$REPO"
+    load_test_context "test"
+    export WT_METADATA_PATTERNS=""
+}
+
+teardown() {
+    teardown_test_env
+}
+
+# =============================================================================
+# Basic adoption
+# =============================================================================
+
+@test "adopt worktree by path argument" {
+    create_branch "$REPO" "feature-a"
+    local wt="$BATS_TEST_TMPDIR/wt/feature-a"
+    create_worktree "$REPO" "$wt" "feature-a"
+    wt="$(cd "$wt" && pwd -P)"
+
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+    assert_is_adopted "$wt"
+}
+
+@test "adopt worktree by branch name" {
+    create_branch "$REPO" "feature-b"
+    create_worktree "$REPO" "$WT_WORKTREES_BASE/feature-b" "feature-b"
+
+    run "$TEST_HOME/.wt/bin/wt-adopt" "feature-b"
+    assert_success
+    assert_is_adopted "$WT_WORKTREES_BASE/feature-b"
+}
+
+@test "adopt worktree at CWD" {
+    create_branch "$REPO" "feature-c"
+    local wt="$BATS_TEST_TMPDIR/wt/feature-c"
+    create_worktree "$REPO" "$wt" "feature-c"
+    wt="$(cd "$wt" && pwd -P)"
+
+    run bash -c 'cd "'"$wt"'" && "'"$TEST_HOME/.wt/bin/wt-adopt"'"'
+    assert_success
+    assert_is_adopted "$wt"
+}
+
+# =============================================================================
+# Idempotency
+# =============================================================================
+
+@test "adopt already-adopted worktree is noop (non-interactive)" {
+    create_branch "$REPO" "feature-d"
+    local wt="$BATS_TEST_TMPDIR/wt/feature-d"
+    create_worktree "$REPO" "$wt" "feature-d"
+    wt="$(cd "$wt" && pwd -P)"
+
+    # Adopt first time
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+
+    # Adopt again (stdin from /dev/null = non-interactive)
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt" < /dev/null
+    assert_success
+    assert_output --partial "already adopted"
+    assert_output --partial "--redo"
+}
+
+# =============================================================================
+# Error cases
+# =============================================================================
+
+@test "adopt main repo fails with error" {
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$REPO"
+    assert_failure
+    assert_output --partial "Cannot adopt the main repository"
+}
+
+@test "adopt non-git-directory fails with error" {
+    local tmpdir="$BATS_TEST_TMPDIR/not-a-repo"
+    mkdir -p "$tmpdir"
+
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$tmpdir"
+    assert_failure
+}
+
+@test "adopt with too many arguments fails" {
+    run "$TEST_HOME/.wt/bin/wt-adopt" arg1 arg2
+    assert_failure
+}
+
+@test "adopt --help shows usage" {
+    run "$TEST_HOME/.wt/bin/wt-adopt" --help
+    assert_success
+    assert_output --partial "Adopt an existing worktree"
+}
+
+# =============================================================================
+# Worktree location flexibility
+# =============================================================================
+
+@test "adopt worktree outside worktrees base directory" {
+    create_branch "$REPO" "feature-outside"
+    local wt="$BATS_TEST_TMPDIR/elsewhere/feature-outside"
+    create_worktree "$REPO" "$wt" "feature-outside"
+    wt="$(cd "$wt" && pwd -P)"
+
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+    assert_is_adopted "$wt"
+}
+
+# =============================================================================
+# Treatment: metadata import
+# =============================================================================
+
+@test "adopt imports metadata when patterns configured" {
+    # Patch .conf for metadata patterns
+    sed -i.bak 's/WT_METADATA_PATTERNS=""/WT_METADATA_PATTERNS=".idea"/' \
+        "$TEST_HOME/.wt/repos/test.conf"
+
+    # Create branch BEFORE metadata dirs so create_branch's "git add ." doesn't
+    # commit .idea (which would remove it from main's working tree on checkout)
+    create_branch "$REPO" "feature-meta"
+
+    # Now create metadata dirs and export to vault
+    create_metadata_dirs "$REPO" ".idea"
+    run "$TEST_HOME/.wt/bin/wt-metadata-export" -y "$REPO" "$WT_IDEA_FILES_BASE"
+    assert_success
+
+    # Create worktree and adopt
+    local wt="$BATS_TEST_TMPDIR/wt/feature-meta"
+    create_worktree "$REPO" "$wt" "feature-meta"
+    wt="$(cd "$wt" && pwd -P)"
+
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+    assert_is_adopted "$wt"
+    # Metadata should be present in worktree
+    assert [ -d "$wt/.idea" ]
+}
+
+# =============================================================================
+# Treatment: Bazel symlinks
+# =============================================================================
+
+@test "adopt installs Bazel symlinks when present" {
+    # Create fake bazel symlinks in main repo
+    ln -s "/fake/bazel/output" "$REPO/bazel-out"
+    ln -s "/fake/bazel/bin" "$REPO/bazel-bin"
+
+    create_branch "$REPO" "feature-bazel"
+    local wt="$BATS_TEST_TMPDIR/wt/feature-bazel"
+    create_worktree "$REPO" "$wt" "feature-bazel"
+    wt="$(cd "$wt" && pwd -P)"
+
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+    assert [ -L "$wt/bazel-out" ]
+    assert [ -L "$wt/bazel-bin" ]
+}
+
+# =============================================================================
+# Conflict safety
+# =============================================================================
+
+@test "adopt aborts non-interactive when worktree has existing metadata" {
+    # Set up patterns and vault
+    sed -i.bak 's/WT_METADATA_PATTERNS=""/WT_METADATA_PATTERNS=".idea"/' \
+        "$TEST_HOME/.wt/repos/test.conf"
+    create_branch "$REPO" "conflict-abort"
+    create_metadata_dirs "$REPO" ".idea"
+    run "$TEST_HOME/.wt/bin/wt-metadata-export" -y "$REPO" "$WT_IDEA_FILES_BASE"
+    assert_success
+
+    # Create worktree and add pre-existing .idea with known content
+    local wt="$BATS_TEST_TMPDIR/wt/conflict-abort"
+    create_worktree "$REPO" "$wt" "conflict-abort"
+    wt="$(cd "$wt" && pwd -P)"
+    mkdir -p "$wt/.idea"
+    echo "original-content" > "$wt/.idea/my-config.xml"
+
+    # Non-interactive: should abort
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt" < /dev/null
+    assert_failure
+    assert_output --partial "existing files"
+
+    # Original .idea should be preserved
+    assert [ -f "$wt/.idea/my-config.xml" ]
+    assert_equal "$(cat "$wt/.idea/my-config.xml")" "original-content"
+
+    # Should NOT be adopted
+    refute_is_adopted "$wt"
+}
+
+@test "adopt with --force overwrites existing metadata" {
+    # Set up patterns and vault
+    sed -i.bak 's/WT_METADATA_PATTERNS=""/WT_METADATA_PATTERNS=".idea"/' \
+        "$TEST_HOME/.wt/repos/test.conf"
+    create_branch "$REPO" "conflict-force"
+    create_metadata_dirs "$REPO" ".idea"
+    run "$TEST_HOME/.wt/bin/wt-metadata-export" -y "$REPO" "$WT_IDEA_FILES_BASE"
+    assert_success
+
+    # Create worktree and add pre-existing .idea
+    local wt="$BATS_TEST_TMPDIR/wt/conflict-force"
+    create_worktree "$REPO" "$wt" "conflict-force"
+    wt="$(cd "$wt" && pwd -P)"
+    mkdir -p "$wt/.idea"
+    echo "will-be-replaced" > "$wt/.idea/old.xml"
+
+    # --force should succeed
+    run "$TEST_HOME/.wt/bin/wt-adopt" --force "$wt"
+    assert_success
+    assert_is_adopted "$wt"
+    # .idea should be replaced with vault contents
+    assert [ -d "$wt/.idea" ]
+}
+
+@test "adopt proceeds when no conflicts exist" {
+    # No metadata patterns, no vault content — clean worktree
+    create_branch "$REPO" "no-conflict"
+    local wt="$BATS_TEST_TMPDIR/wt/no-conflict"
+    create_worktree "$REPO" "$wt" "no-conflict"
+    wt="$(cd "$wt" && pwd -P)"
+
+    # Non-interactive should succeed (no conflicts)
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt" < /dev/null
+    assert_success
+    assert_is_adopted "$wt"
+}
+
+# =============================================================================
+# --redo flag
+# =============================================================================
+
+@test "--redo re-runs treatment on adopted worktree" {
+    create_branch "$REPO" "redo-test"
+    local wt="$BATS_TEST_TMPDIR/wt/redo-test"
+    create_worktree "$REPO" "$wt" "redo-test"
+    wt="$(cd "$wt" && pwd -P)"
+
+    # First adopt
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+    assert_is_adopted "$wt"
+
+    # Re-run with --redo --force
+    run "$TEST_HOME/.wt/bin/wt-adopt" --redo --force "$wt"
+    assert_success
+    assert_output --partial "Re-running adoption treatment"
+    assert_is_adopted "$wt"
+}
+
+@test "--redo on unadopted worktree just adopts" {
+    create_branch "$REPO" "redo-unadopted"
+    local wt="$BATS_TEST_TMPDIR/wt/redo-unadopted"
+    create_worktree "$REPO" "$wt" "redo-unadopted"
+    wt="$(cd "$wt" && pwd -P)"
+
+    run "$TEST_HOME/.wt/bin/wt-adopt" --redo "$wt"
+    assert_success
+    assert_is_adopted "$wt"
+}
+
+@test "already adopted without --redo shows info and hint" {
+    create_branch "$REPO" "hint-test"
+    local wt="$BATS_TEST_TMPDIR/wt/hint-test"
+    create_worktree "$REPO" "$wt" "hint-test"
+    wt="$(cd "$wt" && pwd -P)"
+
+    # First adopt
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+
+    # Run again without --redo
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+    assert_output --partial "already adopted"
+    assert_output --partial "--redo"
+}
+
+@test "--redo without --force still checks conflicts on re-run" {
+    # Set up patterns and vault
+    sed -i.bak 's/WT_METADATA_PATTERNS=""/WT_METADATA_PATTERNS=".idea"/' \
+        "$TEST_HOME/.wt/repos/test.conf"
+    create_branch "$REPO" "redo-conflict"
+    create_metadata_dirs "$REPO" ".idea"
+    run "$TEST_HOME/.wt/bin/wt-metadata-export" -y "$REPO" "$WT_IDEA_FILES_BASE"
+    assert_success
+
+    # Create worktree, adopt with --force (first time)
+    local wt="$BATS_TEST_TMPDIR/wt/redo-conflict"
+    create_worktree "$REPO" "$wt" "redo-conflict"
+    wt="$(cd "$wt" && pwd -P)"
+    run "$TEST_HOME/.wt/bin/wt-adopt" --force "$wt"
+    assert_success
+    assert_is_adopted "$wt"
+
+    # Now .idea exists in worktree (from vault import).
+    # --redo without --force in non-interactive → should abort due to conflict
+    run "$TEST_HOME/.wt/bin/wt-adopt" --redo "$wt" < /dev/null
+    assert_failure
+    assert_output --partial "existing files"
+}
+
+@test "--force on already adopted re-runs treatment" {
+    create_branch "$REPO" "force-redo"
+    local wt="$BATS_TEST_TMPDIR/wt/force-redo"
+    create_worktree "$REPO" "$wt" "force-redo"
+    wt="$(cd "$wt" && pwd -P)"
+
+    # First adopt
+    run "$TEST_HOME/.wt/bin/wt-adopt" "$wt"
+    assert_success
+
+    # --force alone on already-adopted should also re-run
+    run "$TEST_HOME/.wt/bin/wt-adopt" --force "$wt"
+    assert_success
+    assert_output --partial "Re-running adoption treatment"
+}
+
+# =============================================================================
+# Keep existing files option
+# =============================================================================
+
+@test "adopt keep preserves existing metadata but installs bazel symlinks" {
+    # Set up patterns and vault
+    sed -i.bak 's/WT_METADATA_PATTERNS=""/WT_METADATA_PATTERNS=".idea"/' \
+        "$TEST_HOME/.wt/repos/test.conf"
+    create_branch "$REPO" "keep-test"
+    create_metadata_dirs "$REPO" ".idea"
+    run "$TEST_HOME/.wt/bin/wt-metadata-export" -y "$REPO" "$WT_IDEA_FILES_BASE"
+    assert_success
+
+    # Create fake bazel symlinks in main repo
+    ln -s "/fake/bazel/output" "$REPO/bazel-out"
+
+    # Create worktree with pre-existing .idea containing known content
+    local wt="$BATS_TEST_TMPDIR/wt/keep-test"
+    create_worktree "$REPO" "$wt" "keep-test"
+    wt="$(cd "$wt" && pwd -P)"
+    mkdir -p "$wt/.idea"
+    echo "my-precious-config" > "$wt/.idea/workspace.xml"
+
+    # Override _wt_is_interactive so the prompt appears even in a pipe,
+    # then pipe "k" (keep) to choose the keep-existing-files option.
+    run bash -c '
+        source "'"$TEST_HOME/.wt/lib/wt-common"'"
+        source "'"$TEST_HOME/.wt/lib/wt-adopt"'"
+        _wt_is_interactive() { return 0; }
+        echo "k" | wt_adopt_worktree "'"$wt"'"
+    '
+    assert_success
+    assert_is_adopted "$wt"
+
+    # .idea should have the ORIGINAL content (not vault)
+    assert [ -f "$wt/.idea/workspace.xml" ]
+    assert_equal "$(cat "$wt/.idea/workspace.xml")" "my-precious-config"
+
+    # Bazel symlinks should still be installed
+    assert [ -L "$wt/bazel-out" ]
+}
+
+# =============================================================================
+# Subdirectory adoption (CWD resolves to worktree root)
+# =============================================================================
+
+@test "adopt from subdirectory resolves to worktree root" {
+    create_branch "$REPO" "subdir-test"
+    local wt="$BATS_TEST_TMPDIR/wt/subdir-test"
+    create_worktree "$REPO" "$wt" "subdir-test"
+    wt="$(cd "$wt" && pwd -P)"
+
+    # Create a subdirectory inside the worktree
+    mkdir -p "$wt/some/deep/subdir"
+
+    # Run wt-adopt from the subdirectory (no arguments = CWD mode)
+    run bash -c 'cd "'"$wt/some/deep/subdir"'" && "'"$TEST_HOME/.wt/bin/wt-adopt"'"'
+    assert_success
+    assert_is_adopted "$wt"
+}
+
+# =============================================================================
+# Metadata import failure prevents adoption
+# =============================================================================
+
+@test "adopt fails and does not stamp marker when metadata import fails" {
+    sed -i.bak 's/WT_METADATA_PATTERNS=""/WT_METADATA_PATTERNS=".idea"/' \
+        "$TEST_HOME/.wt/repos/test.conf"
+
+    # Create vault so the -d check passes
+    mkdir -p "$WT_IDEA_FILES_BASE/.idea"
+
+    # Replace wt-metadata-import with a stub that always fails
+    cat > "$TEST_HOME/.wt/bin/wt-metadata-import" <<'STUB'
+#!/usr/bin/env bash
+echo "simulated import failure" >&2
+exit 1
+STUB
+    chmod +x "$TEST_HOME/.wt/bin/wt-metadata-import"
+
+    create_branch "$REPO" "import-fail"
+    local wt="$BATS_TEST_TMPDIR/wt/import-fail"
+    create_worktree "$REPO" "$wt" "import-fail"
+    wt="$(cd "$wt" && pwd -P)"
+
+    run "$TEST_HOME/.wt/bin/wt-adopt" --force "$wt"
+    assert_failure
+    assert_output --partial "import failed"
+
+    # Should NOT be adopted
+    refute_is_adopted "$wt"
+}
diff --git a/test/test_helper/common.bash b/test/test_helper/common.bash
index 93fe91f..b07bdd1 100644
--- a/test/test_helper/common.bash
+++ b/test/test_helper/common.bash
@@ -272,3 +272,25 @@ skip_if_no_git() {
         skip "Test requires git"
     fi
 }
+
+# Check if a worktree has the adoption marker
+assert_is_adopted() {
+    local worktree="$1"
+    local git_dir
+    git_dir="$(git -C "$worktree" rev-parse --git-dir)"
+    if [[ "$git_dir" != /* ]]; then
+        git_dir="$(cd "$worktree" && cd "$git_dir" && pwd -P)"
+    fi
+    assert [ -f "$git_dir/wt/adopted" ]
+}
+
+# Check that a worktree does NOT have the adoption marker
+refute_is_adopted() {
+    local worktree="$1"
+    local git_dir
+    git_dir="$(git -C "$worktree" rev-parse --git-dir)"
+    if [[ "$git_dir" != /* ]]; then
+        git_dir="$(cd "$worktree" && cd "$git_dir" && pwd -P)"
+    fi
+    assert [ ! -f "$git_dir/wt/adopted" ]
+}
diff --git a/test/unit/wt-adopt.bats b/test/unit/wt-adopt.bats
new file mode 100644
index 0000000..1a95198
--- /dev/null
+++ b/test/unit/wt-adopt.bats
@@ -0,0 +1,201 @@
+#!/usr/bin/env bats
+
+# Unit tests for lib/wt-adopt
+
+setup() {
+    load '../test_helper/common'
+    setup_test_env
+    source "$TEST_HOME/.wt/lib/wt-common"
+    source "$TEST_HOME/.wt/lib/wt-adopt"
+
+    REPO=$(create_mock_repo "$BATS_TEST_TMPDIR/repo")
+    create_branch "$REPO" "test-branch"
+
+    WORKTREE="$BATS_TEST_TMPDIR/wt/test-branch"
+    create_worktree "$REPO" "$WORKTREE" "test-branch"
+    # Normalize path for consistent comparisons
+    WORKTREE="$(cd "$WORKTREE" && pwd -P)"
+
+    export WT_MAIN_REPO_ROOT="$REPO"
+}
+
+teardown() {
+    teardown_test_env
+}
+
+# =============================================================================
+# wt_is_adopted / wt_mark_adopted / wt_unmark_adopted
+# =============================================================================
+
+@test "wt_is_adopted returns false for fresh worktree" {
+    run wt_is_adopted "$WORKTREE"
+    assert_failure
+}
+
+@test "wt_mark_adopted creates marker file in correct git-dir location" {
+    wt_mark_adopted "$WORKTREE"
+
+    # Marker should be inside the worktree's git dir, NOT in the working tree
+    local git_dir
+    git_dir="$(git -C "$WORKTREE" rev-parse --git-dir)"
+    if [[ "$git_dir" != /* ]]; then
+        git_dir="$(cd "$WORKTREE" && cd "$git_dir" && pwd -P)"
+    fi
+    assert [ -f "$git_dir/wt/adopted" ]
+    # In a worktree, .git is a file, not a directory — marker should NOT be at .git/wt/adopted
+    assert [ ! -d "$WORKTREE/.git/wt" ]
+}
+
+@test "wt_is_adopted returns true after marking" {
+    wt_mark_adopted "$WORKTREE"
+    run wt_is_adopted "$WORKTREE"
+    assert_success
+}
+
+@test "wt_unmark_adopted removes marker and wt directory" {
+    wt_mark_adopted "$WORKTREE"
+    run wt_is_adopted "$WORKTREE"
+    assert_success
+
+    wt_unmark_adopted "$WORKTREE"
+    run wt_is_adopted "$WORKTREE"
+    assert_failure
+
+    # wt/ directory should also be cleaned up
+    local git_dir
+    git_dir="$(git -C "$WORKTREE" rev-parse --git-dir)"
+    if [[ "$git_dir" != /* ]]; then
+        git_dir="$(cd "$WORKTREE" && cd "$git_dir" && pwd -P)"
+    fi
+    assert [ ! -d "$git_dir/wt" ]
+}
+
+@test "wt_mark_adopted is idempotent" {
+    wt_mark_adopted "$WORKTREE"
+    wt_mark_adopted "$WORKTREE"
+    run wt_is_adopted "$WORKTREE"
+    assert_success
+}
+
+# =============================================================================
+# wt_is_main_repo
+# =============================================================================
+
+@test "wt_is_main_repo returns true for main repo" {
+    run wt_is_main_repo "$REPO"
+    assert_success
+}
+
+@test "wt_is_main_repo returns false for worktree" {
+    run wt_is_main_repo "$WORKTREE"
+    assert_failure
+}
+
+@test "wt_is_main_repo returns failure for non-git directory" {
+    local tmpdir="$BATS_TEST_TMPDIR/not-a-repo"
+    mkdir -p "$tmpdir"
+    run wt_is_main_repo "$tmpdir"
+    assert_failure
+}
+
+# =============================================================================
+# wt_install_bazel_symlinks
+# =============================================================================
+
+@test "wt_install_bazel_symlinks copies symlinks from main repo" {
+    # Create fake bazel symlinks in main repo
+    ln -s "/fake/bazel/output" "$REPO/bazel-out"
+    ln -s "/fake/bazel/bin" "$REPO/bazel-bin"
+
+    wt_install_bazel_symlinks "$WORKTREE"
+
+    assert [ -L "$WORKTREE/bazel-out" ]
+    assert [ -L "$WORKTREE/bazel-bin" ]
+    local target
+    target="$(readlink "$WORKTREE/bazel-out")"
+    assert_equal "$target" "/fake/bazel/output"
+}
+
+@test "wt_install_bazel_symlinks skips missing symlinks" {
+    # Main repo has no bazel symlinks
+    wt_install_bazel_symlinks "$WORKTREE"
+
+    assert [ ! -L "$WORKTREE/bazel-out" ]
+    assert [ ! -L "$WORKTREE/bazel-bin" ]
+}
+
+# =============================================================================
+# wt_check_adoption_conflicts
+# =============================================================================
+
+@test "wt_check_adoption_conflicts returns 1 when no conflicts" {
+    export WT_METADATA_PATTERNS=".idea"
+    # Empty vault, empty worktree
+    mkdir -p "$BATS_TEST_TMPDIR/vault"
+    export WT_IDEA_FILES_BASE="$BATS_TEST_TMPDIR/vault"
+
+    run wt_check_adoption_conflicts "$WORKTREE"
+    assert_failure  # return 1 = no conflicts
+}
+
+@test "wt_check_adoption_conflicts detects metadata from vault scan" {
+    export WT_METADATA_PATTERNS=".idea"
+    mkdir -p "$BATS_TEST_TMPDIR/vault/.idea"
+    export WT_IDEA_FILES_BASE="$BATS_TEST_TMPDIR/vault"
+
+    # Create matching .idea in worktree
+    mkdir -p "$WORKTREE/.idea"
+
+    run wt_check_adoption_conflicts "$WORKTREE"
+    assert_success  # return 0 = conflicts found
+    assert_output --partial ".idea"
+}
+
+@test "wt_check_adoption_conflicts detects nested metadata from vault" {
+    export WT_METADATA_PATTERNS=".ijwb"
+    mkdir -p "$BATS_TEST_TMPDIR/vault/subdir/.ijwb"
+    export WT_IDEA_FILES_BASE="$BATS_TEST_TMPDIR/vault"
+
+    # Create matching nested path in worktree
+    mkdir -p "$WORKTREE/subdir/.ijwb"
+
+    run wt_check_adoption_conflicts "$WORKTREE"
+    assert_success
+    assert_output --partial "subdir/.ijwb"
+}
+
+@test "wt_check_adoption_conflicts skips metadata not in vault" {
+    export WT_METADATA_PATTERNS=".idea"
+    # Vault exists but does NOT contain .idea
+    mkdir -p "$BATS_TEST_TMPDIR/vault"
+    export WT_IDEA_FILES_BASE="$BATS_TEST_TMPDIR/vault"
+
+    # Worktree has .idea but vault doesn't → no conflict
+    mkdir -p "$WORKTREE/.idea"
+
+    run wt_check_adoption_conflicts "$WORKTREE"
+    assert_failure  # no conflicts
+}
+
+@test "wt_check_adoption_conflicts ignores bazel symlinks" {
+    export WT_METADATA_PATTERNS=""
+    export WT_IDEA_FILES_BASE=""
+
+    # Create bazel-out as a symlink in worktree
+    ln -s "/some/target" "$WORKTREE/bazel-out"
+
+    run wt_check_adoption_conflicts "$WORKTREE"
+    assert_failure  # no conflicts (symlinks are safe)
+}
+
+@test "wt_check_adoption_conflicts detects bazel real directory" {
+    export WT_METADATA_PATTERNS=""
+    export WT_IDEA_FILES_BASE=""
+
+    # Create bazel-out as a real directory in worktree
+    mkdir -p "$WORKTREE/bazel-out"
+
+    run wt_check_adoption_conflicts "$WORKTREE"
+    assert_success
+    assert_output --partial "bazel-out (real directory)"
+}
diff --git a/test/unit/wt-sh.bats b/test/unit/wt-sh.bats
index 7d120cb..d0a9705 100644
--- a/test/unit/wt-sh.bats
+++ b/test/unit/wt-sh.bats
@@ -15,6 +15,10 @@ teardown() {
 # Tests for _WT_ROOT consistency
 # =============================================================================
 
+@test "wt.sh dispatches adopt subcommand" {
+    grep -q 'adopt)' "$PROJECT_ROOT/wt.sh"
+}
+
 @test "_WT_ROOT default in wt.sh matches INSTALL_DIR in install.sh" {
     # Extract the default path from wt.sh: _WT_ROOT="${_WT_ROOT:-$HOME/.wt}"
     local wt_line
diff --git a/wt.sh b/wt.sh
index e27b066..1f1d36c 100755
--- a/wt.sh
+++ b/wt.sh
@@ -91,6 +91,7 @@ wt() {
 
   case "$cmd" in
     add)             _wt_run wt-add "$@" ;;
+    adopt)           _wt_run wt-adopt "$@" ;;
     switch)          _wt_run wt-switch "$@" ;;
     remove)          _wt_run wt-remove "$@" ;;
     list)            _wt_run wt-list "$@" ;;