diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ddcf2d4d..4fa80aa0 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -69,7 +69,7 @@ This project operates under professional standards of conduct. All contributors:
 | File/Directory                      | Purpose                                                    |
 | ----------------------------------- | ---------------------------------------------------------- |
 | `acq`                               | Entry point — pluggable-backend wrapper (msb by default, or sbx) |
-| `acq.backends/`                     | Backend adapters (`common.sh`, `sbx.sh`, `msb.sh`, `kit-translate.sh`, `secret-store.sh`, `progress.sh`) |
+| `acq.backends/`                     | Backend adapters (`common.sh`, `sbx.sh`, `msb.sh`, `kit-translate.sh`, `secret-store.sh`, `progress.sh`, `prompt.sh`) |
 | `install.sh`                        | One-line `curl \| sh` installer (auto-selects brew/npm/clone; direct `sh install.sh` still installs the default release tag from the repo, not the current checkout) |
 | `scripts/rotate-apikey`             | Rotate your USAi API key secret (`acq usai-rotate-api-key`) |
 | `scripts/test-acq-bats`             | Offline unit suite for acq (bats-core) |
diff --git a/acq b/acq
index 00584b6e..a37f1ded 100755
--- a/acq
+++ b/acq
@@ -111,6 +111,9 @@ Subcommands:
   backend list                             List detected backends (sbx, msb).
   backend set NAME                         Persist the default backend.
   backend unset                            Clear the persisted default (auto-detect).
+  configure                                Interactive setup: pick extra kits and
+                                           the per-sandbox token-scoping default
+                                           (persists to config.yaml).
   kit list                                 Show the pinned kits (+ extras).
   kit validate PATH                        Validate a neutral hybrid/v1 kit.
   kit apply NAME KITREF                    Apply a kit to an existing sandbox.
@@ -224,6 +227,26 @@ Usage:
 BACKENDUSAGE
 }
 
+_acq_configure_usage() {
+  cat >&2 <<'CONFIGUSAGE'
+acq configure — interactive setup for extra kits and token scoping (ADR-0031)
+
+Usage:
+  acq configure
+
+Opens an interactive picker to choose which OPT-IN kits to enable (the four
+built-in kits are always applied) and to set the DEFAULT answer for the
+per-sandbox GitHub-token-scoping prompt. Choices persist to
+~/.config/acq/config.yaml and pre-populate the picker shown at `acq create`,
+where a single sandbox may deviate without changing the global default.
+
+Non-interactive (CI / piped) invocations make no changes and just print the
+current configuration. Set ACQ_NO_PROMPT=1 to force this behavior. The
+GitHub-token preference only pre-answers the existing scoping prompt; the
+fine-grained PAT is still minted per-sandbox (see `acq github-scope`).
+CONFIGUSAGE
+}
+
 # _acq_simple_verb_usage VERB — acq's OWN one-verb usage for the remaining
 # acq-owned top-level verbs that are NOT the multi-word topics (secret/kit/
 # backend) handled above. Kept as a single source (one case) so `acq VERB --help`
@@ -428,10 +451,11 @@ _acq_print_topic_help() {
   local topic="$1" head
   head="${topic%% *}"
   case "$head" in
-    secret)  _acq_secret_usage; return 0 ;;
-    kit)     _acq_kit_usage; return 0 ;;
-    backend) _acq_backend_subcmd_usage; return 0 ;;
-    *)       _acq_simple_verb_usage "$head"; return $? ;;
+    secret)    _acq_secret_usage; return 0 ;;
+    kit)       _acq_kit_usage; return 0 ;;
+    backend)   _acq_backend_subcmd_usage; return 0 ;;
+    configure) _acq_configure_usage; return 0 ;;
+    *)         _acq_simple_verb_usage "$head"; return $? ;;
   esac
 }
 
@@ -684,17 +708,24 @@ case "$subcommand" in
         local_backend="${1:-}"
         [ -z "$local_backend" ] && { echo "acq: backend set: missing backend name" >&2; exit 1; }
         local_config_file="${XDG_CONFIG_HOME:-$HOME/.config}/acq/config.yaml"
-        mkdir -p "$(dirname "$local_config_file")"
-        printf 'backend: %s\n' "$local_backend" > "$local_config_file"
+        # Write only the `backend:` key, preserving any other config (extra_kits,
+        # scope_github_token) written by `acq configure` (ADR-0031).
+        _acq_config_write_field backend "$local_backend" \
+          || { echo "acq: backend set: could not write ${local_config_file}" >&2; exit 1; }
         echo "acq: default backend set to '${local_backend}' in ${local_config_file}" >&2
         ;;
       unset)
-        # Clear the persisted default so acq falls back to auto-detection (see
-        # the resolution order in `acq help`). Idempotent: succeeds whether or
-        # not a default was set.
+        # Clear ONLY the persisted default backend so acq falls back to
+        # auto-detection (see the resolution order in `acq help`). Preserves any
+        # other config keys (extra_kits, scope_github_token). Idempotent.
         local_config_file="${XDG_CONFIG_HOME:-$HOME/.config}/acq/config.yaml"
-        if [ -f "$local_config_file" ]; then
-          rm -f "$local_config_file"
+        if [ -f "$local_config_file" ] && [ -n "$(_acq_config_read_field backend)" ]; then
+          _acq_config_write_field backend ""   # empty value removes the key
+          # If the config is now empty (backend was the only key), remove the
+          # file so a fresh checkout looks pristine — matching the historical
+          # behavior and the first-run detection (a stale empty file would
+          # suppress the first-run `acq configure` offer).
+          [ -s "$local_config_file" ] || rm -f "$local_config_file" 2>/dev/null || true
           echo "acq: cleared the persisted default backend (${local_config_file}); acq will auto-detect." >&2
         else
           echo "acq: no persisted default backend was set; acq already auto-detects." >&2
@@ -858,6 +889,16 @@ esac
 # version/doctor: resolve backend best-effort (they work even if none detected).
 # ---------------------------------------------------------------------------
 case "$subcommand" in
+  configure)
+    # Interactive configuration (ADR-0031). Needs no backend — it only reads and
+    # writes config.yaml. Resolve the backend best-effort so a first-run decline
+    # can persist the detected default, but never fail on no backend.
+    shift
+    acq_resolve_backend "${explicit_backend}" 2>/dev/null || true
+    acq_configure
+    exit 0
+    ;;
+
   version|--version|-v)
     # Resolve backend best-effort so version can report it; don't fail.
     acq_resolve_backend "${explicit_backend}" 2>/dev/null || true
@@ -959,6 +1000,15 @@ case "$subcommand" in
   create)
     shift
     acq_backend_prepare
+    # First-run onboarding (ADR-0031): offer `acq configure` once before we
+    # provision, so a brand-new user picks kits up front. No-op after first run
+    # and in non-interactive sessions.
+    maybe_first_run_configure
+    # Apply configured-default extra kits (config.yaml), then offer a create-time
+    # picker pre-populated with those defaults so THIS sandbox can deviate.
+    _acq_apply_configured_extra_kits || exit 1
+    create_time_kit_picker
+    _build_kit_list
     # Pre-flight: validate the workspace path before provisioning (#issue).
     ws=$(workspace_path "$@")
     preflight_workspace_path "$ws" || exit 1
@@ -1078,6 +1128,17 @@ case "$subcommand" in
         # with no USAi binding — the exact split that made validation report 200
         # (in a throwaway sandbox) yet 401 (in the real one). Gate on key
         # presence first; fail closed if the user declines.
+
+        # First-run onboarding + extra-kit selection (ADR-0031), BEFORE the key
+        # gate so a first-time user configures kits up front. maybe_first_run_*
+        # is a no-op after first run / non-interactive; the picker pre-populates
+        # from the configured defaults and folds the result into ACQ_EXTRA_KITS
+        # for this create (persisted per-sandbox by the existing kit-record path).
+        maybe_first_run_configure
+        _acq_apply_configured_extra_kits || exit 1
+        create_time_kit_picker
+        _build_kit_list
+
         if ! ensure_key_present "$local_name"; then
           exit 1
         fi
diff --git a/acq.backends/common.sh b/acq.backends/common.sh
index 8b2b5906..6ad521c1 100644
--- a/acq.backends/common.sh
+++ b/acq.backends/common.sh
@@ -58,6 +58,16 @@ GITSSHSIGN_KIT="${PATTERNS_KIT_REPO}#ref=${PATTERNS_KIT_REF}&dir=${PATTERNS_KIT_
 # shellcheck disable=SC2034  # consumed by `acq kit list` in the acq entry point
 ACQ_KIT_NAMES=(zscaler-ca-certificate usai-provider agentic-coding-playbook git-ssh-sign)
 
+# One-line descriptions for the built-in kits, parallel to ACQ_KIT_NAMES, shown
+# as the frozen ("always applied") rows in the `acq configure` picker (ADR-0031).
+# shellcheck disable=SC2034  # consumed by acq_configure / create_time_kit_picker
+ACQ_KIT_DESCS=(
+  "Zscaler/corporate CA trust so TLS-intercepting proxies don't break fetches"
+  "USAi provider + model config for OpenCode (endpoints, key wiring)"
+  "Federal agent rules and skills from the agentic-coding playbook"
+  "SSH-based git commit signing for the agent's commits"
+)
+
 # Built-in bundle identity. This mirrors the `provenance` block the usai-provider
 # kit declares at the pinned PATTERNS_KIT_REF. acq records these in a sandbox's
 # record so a later `acq run` / `acq kit check` can tell whether an existing
@@ -73,6 +83,93 @@ ACQ_BUILTIN_BUNDLE_REPO="GSA-TTS/agentic-coding-patterns"
 ACQ_EXTRA_KITS="${ACQ_EXTRA_KITS:-}"
 ACQ_EXTRA_KIT_SOURCES="${ACQ_EXTRA_KIT_SOURCES:-}"
 
+# Record whether ACQ_EXTRA_KITS came from the ENVIRONMENT (vs. being empty or set
+# later by acq itself). The configured-default and create-time picker paths honor
+# env > config > interactive: a user who exported ACQ_EXTRA_KITS gets it verbatim
+# and is never re-prompted or overridden (ADR-0031). Captured once at load time.
+if [ -n "${ACQ_EXTRA_KITS:-}" ]; then
+  ACQ_EXTRA_KITS_FROM_ENV=1
+else
+  ACQ_EXTRA_KITS_FROM_ENV=""
+fi
+
+# ---------------------------------------------------------------------------
+# Opt-in kit catalog (for `acq configure`; ADR-0031)
+# ---------------------------------------------------------------------------
+# The OPT-IN community kits acq can offer in the interactive picker, sourced from
+# the SAME pinned patterns bundle as the built-ins (PATTERNS_KIT_REF /
+# PATTERNS_KIT_DIR) so their refs stay pinned in lockstep. The four built-in kits
+# above are always applied and are NOT listed here (the picker shows them as
+# locked/pre-checked, informational only).
+#
+# Parallel arrays (bash 3.2 safe — no associative arrays): NAME[i] is the kit
+# directory under PATTERNS_KIT_DIR; DESC[i] is the one-line picker description.
+# `prime-agent` is intentionally omitted: it is a skeleton at the current pin
+# (see the patterns kits.yaml parity note) and would be non-functional if
+# offered. Add it here once it is functional.
+# shellcheck disable=SC2034  # consumed by `acq configure` (cross-function reader)
+ACQ_OPTIN_KIT_NAMES=(openchamber paseo)
+# shellcheck disable=SC2034
+ACQ_OPTIN_KIT_DESCS=(
+  "Browser UI for OpenCode alongside the terminal TUI (publishes ports 3000/4096)"
+  "Self-hosted Paseo browser web UI for coding agents (one port, loopback only)"
+)
+
+# _acq_optin_kit_ref NAME — echo the fully-pinned git+https kit ref for an opt-in
+# kit NAME, built exactly like the built-in *_KIT refs (same repo/ref/dir), so a
+# picked kit is pinned to the same patterns bundle as everything else.
+_acq_optin_kit_ref() {
+  printf '%s#ref=%s&dir=%s/%s\n' \
+    "$PATTERNS_KIT_REPO" "$PATTERNS_KIT_REF" "$PATTERNS_KIT_DIR" "${1:?kit name required}"
+}
+
+# _acq_apply_configured_extra_kits — fold the configured-default extra kits
+# (config.yaml `extra_kits:`, written by `acq configure`) into ACQ_EXTRA_KITS for
+# this invocation, so a durable default behaves like an env-supplied extra. An
+# env-supplied ACQ_EXTRA_KITS is authoritative and is NOT overridden (env > config,
+# matching the backend-resolution precedence and the `--kit`/env layering). No-op
+# when nothing is configured. Idempotent (guarded so a second call is cheap).
+_ACQ_CONFIGURED_KITS_APPLIED=""
+_acq_apply_configured_extra_kits() {
+  [ -z "$_ACQ_CONFIGURED_KITS_APPLIED" ] || return 0
+  # Env wins: if the user exported ACQ_EXTRA_KITS, respect it verbatim.
+  if [ -n "${ACQ_EXTRA_KITS_FROM_ENV:-}" ]; then
+    _ACQ_CONFIGURED_KITS_APPLIED=1
+    return 0
+  fi
+  local configured names ref
+  configured=$(_acq_config_read_field extra_kits)
+  if [ -z "$configured" ]; then
+    _ACQ_CONFIGURED_KITS_APPLIED=1
+    return 0
+  fi
+  # The stored value is a list of opt-in kit NAMES. Raw refs are intentionally
+  # not accepted from durable config; use ACQ_EXTRA_KITS or --kit for those.
+  names="$configured"
+  local out="" tok known k
+  for tok in $names; do
+    known=""
+    for k in ${ACQ_OPTIN_KIT_NAMES[@]+"${ACQ_OPTIN_KIT_NAMES[@]}"}; do
+      [ "$k" = "$tok" ] && { known=1; break; }
+    done
+    if [ -z "$known" ]; then
+      echo "acq: config extra_kits contains unknown kit '${tok}'" >&2
+      echo "     Run 'acq configure' to choose catalog kits, or use ACQ_EXTRA_KITS/--kit for custom refs." >&2
+      return 1
+    fi
+    ref=$(_acq_optin_kit_ref "$tok")
+    out="${out:+$out }$ref"
+  done
+  if [ -z "$out" ]; then
+    _ACQ_CONFIGURED_KITS_APPLIED=1
+    return 0
+  fi
+  ACQ_EXTRA_KITS="$out"
+  _ACQ_CONFIGURED_KITS_APPLIED=1
+  acq_debug "config: applied configured extra_kits: $out"
+  return 0
+}
+
 # Update-check opt-out. When ACQ_UPDATE_CHECK=0, `acq run` never
 # runs the stale-sandbox check (no provenance comparison, no prompt). The
 # explicit `acq kit check` / `acq kit update` commands still work — the opt-out
@@ -139,6 +236,22 @@ if ! command -v acq_status >/dev/null 2>&1; then
   acq_spin_stop()  { :; }
 fi
 
+# Source the TTY-aware interactive prompt widgets (acq_prompt_multiselect /
+# acq_prompt_confirm) used by `acq configure` and the create-time picker (see
+# ADR-0031). Like progress.sh, all chrome is stderr-only and gated on an
+# interactive TTY; non-interactive callers take documented defaults and never
+# block. If the file is missing (older partial checkout), define no-op fallbacks
+# so `acq configure` degrades to "take defaults" rather than breaking.
+if [ -n "${ACQ_SCRIPT_DIR:-}" ] && [ -f "${ACQ_SCRIPT_DIR}/acq.backends/prompt.sh" ]; then
+  # shellcheck disable=SC1091
+  . "${ACQ_SCRIPT_DIR}/acq.backends/prompt.sh"
+fi
+if ! command -v acq_prompt_confirm >/dev/null 2>&1; then
+  # Fallback: echo nothing selected / honor the passed default (arg 2 = yes|no).
+  acq_prompt_multiselect() { printf '\n'; }
+  acq_prompt_confirm()     { [ "${2:-no}" = "yes" ] && return 0 || return 1; }
+fi
+
 # ============================================================================
 # Utility functions
 # ============================================================================
@@ -1031,11 +1144,112 @@ _acq_config_file() {
 }
 
 _read_config_backend() {
-  local cfg
+  _acq_config_read_field backend
+}
+
+# _acq_config_read_field KEY — echo the value of a flat `KEY: value` line from
+# config.yaml (empty if the file or key is absent). Defensive awk parse, no YAML
+# dependency — the same convention as the original single-key backend reader,
+# generalized to any flat scalar key (backend, extra_kits, scope_github_token).
+# KEY is matched literally at column 1. Indented keys are deliberately ignored:
+# this is a flat config file, not a general YAML parser. Inline comments and
+# simple single/double-quoted scalars are accepted for hand-edited YAML. If
+# duplicate top-level keys exist, the last one wins, matching the writer's
+# replace-all behavior. A non-identifier KEY is rejected so a caller can't inject
+# an awk regex.
+_acq_config_read_field() {
+  local key="${1:-}" cfg
+  case "$key" in
+    ''|*[!A-Za-z0-9_]*) return 0 ;;   # fail closed on an unexpected key name
+  esac
   cfg=$(_acq_config_file)
   [ -f "$cfg" ] || return 0
-  # Parse the single `backend: <name>` key defensively with awk (no YAML dep).
-  awk '/^[[:space:]]*backend[[:space:]]*:/ { gsub(/^[[:space:]]*backend[[:space:]]*:[[:space:]]*/,""); gsub(/[[:space:]]*$/,""); print; exit }' "$cfg"
+  awk -v k="$key" '
+    {
+      # Match only a top-level flat key: key, optional space, colon.
+      pat = "^" k "[[:space:]]*:"
+      if ($0 ~ pat) {
+        sub(pat "[[:space:]]*", "")     # strip through the colon + spaces
+        line = $0
+        q = sprintf("%c", 39)
+        if (substr(line, 1, 1) == "\"" || substr(line, 1, 1) == q) {
+          in_single = 0
+          in_double = 0
+          for (i = 1; i <= length(line); i++) {
+            c = substr(line, i, 1)
+            if (c == q && !in_double) {
+              in_single = !in_single
+            } else if (c == "\"" && !in_single) {
+              in_double = !in_double
+            } else if (c == "#" && !in_single && !in_double && (i == 1 || substr(line, i - 1, 1) ~ /[[:space:]]/)) {
+              line = substr(line, 1, i - 1)
+              break
+            }
+          }
+        } else if (line ~ /^#/) {
+          line = ""
+        } else {
+          sub(/[[:space:]]+#.*$/, "", line)
+        }
+        $0 = line                         # tolerate inline comments outside quotes
+        sub(/[[:space:]]*$/, "")         # strip trailing space
+        q = sprintf("%c", 39)
+        if ($0 ~ /^"[^"]*"$/) {
+          sub(/^"/, "")
+          sub(/"$/, "")
+        } else if (substr($0, 1, 1) == q && substr($0, length($0), 1) == q) {
+          $0 = substr($0, 2, length($0) - 2)
+        }
+        val = $0                         # last duplicate key wins
+      }
+    }
+    END {
+      if (val != "") print val
+    }
+  ' "$cfg"
+}
+
+# _acq_config_write_field KEY VALUE — set (or replace) a flat `KEY: VALUE` line in
+# config.yaml, preserving every OTHER line (so writing extra_kits leaves backend
+# untouched, and vice-versa). Creates the file + parent dir on first write. An
+# empty VALUE removes the key entirely (so "no extras" is represented by absence,
+# not an empty-valued line). Atomic (temp file + mv). Best-effort: a write failure
+# warns via acq_debug and returns non-zero but never aborts the caller.
+_acq_config_write_field() {
+  local key="${1:-}" value="${2:-}" cfg dir tmp
+  case "$key" in
+    ''|*[!A-Za-z0-9_]*) acq_debug "config: refusing to write unsafe key '$key'"; return 1 ;;
+  esac
+  cfg=$(_acq_config_file)
+  dir=$(dirname "$cfg")
+  if ! ( umask 077; mkdir -p "$dir" ) 2>/dev/null; then
+    acq_debug "config: could not create config dir: $dir"
+    return 1
+  fi
+  chmod 700 "$dir" 2>/dev/null || { acq_debug "config: chmod failed: $dir"; return 1; }
+  tmp="${cfg}.tmp.$$"
+  {
+    # Re-emit every existing line except the one for KEY (which we replace/drop).
+    if [ -f "$cfg" ]; then
+      awk -v k="$key" '
+        {
+          pat = "^" k "[[:space:]]*:"
+          if ($0 ~ pat) next     # drop the old top-level KEY line; we re-add below
+          print
+        }
+      ' "$cfg"
+    fi
+    # Append the new value only when non-empty (empty VALUE => remove the key).
+    # Use an explicit if (not `[ ] &&`) so the group's exit status reflects the
+    # write, not a false test when VALUE is empty.
+    if [ -n "$value" ]; then
+      printf '%s: %s\n' "$key" "$value"
+    fi
+  } > "$tmp" 2>/dev/null || { acq_debug "config: write failed: $tmp"; rm -f "$tmp" 2>/dev/null; return 1; }
+  chmod 600 "$tmp" 2>/dev/null || { acq_debug "config: chmod failed: $tmp"; rm -f "$tmp" 2>/dev/null; return 1; }
+  mv -f "$tmp" "$cfg" 2>/dev/null || { acq_debug "config: mv failed: $cfg"; rm -f "$tmp" 2>/dev/null; return 1; }
+  acq_debug "config: wrote ${key}"
+  return 0
 }
 
 # _ensure_local_bin_on_path — if a backend CLI is not on PATH but IS present in
@@ -2267,13 +2481,20 @@ advise_github_scope() {
     return 0
   fi
 
-  local ans=""
-  printf 'acq: scope a GitHub token for this sandbox now? [y/N] ' >&2
-  read -r ans 2>/dev/null || ans=""
-  case "$ans" in
-    y|Y|yes|YES) github_scope_sandbox "$sandbox" "$ws" || true ;;
-    *) echo "acq: continuing without scoping (run 'acq github-scope $sandbox $ws' anytime)." >&2 ;;
-  esac
+  # The configured default (ADR-0031) pre-answers this prompt: `acq configure`
+  # can set scope_github_token: yes|no in config.yaml. Default is "no" (a bare
+  # ENTER declines), preserving the historical behavior when unset. This only
+  # changes the DEFAULT answer — the actual per-sandbox fine-grained-PAT minting
+  # still runs through github_scope_sandbox (ADR-0013 unchanged).
+  local scope_default
+  scope_default=$(_acq_config_read_field scope_github_token)
+  case "$scope_default" in yes|y|Y) scope_default="yes" ;; *) scope_default="no" ;; esac
+
+  if acq_prompt_confirm "Scope a GitHub token for this sandbox now?" "$scope_default"; then
+    github_scope_sandbox "$sandbox" "$ws"
+  else
+    echo "acq: continuing without scoping (run 'acq github-scope $sandbox $ws' anytime)." >&2
+  fi
   return 0
 }
 
@@ -2650,10 +2871,9 @@ acq_print_doctor() {
   read -r answer || true
   case "$answer" in
     [yY]|[yY][eE][sS])
-      local cfg_dir
-      cfg_dir=$(dirname "$config_file")
-      mkdir -p "$cfg_dir"
-      printf 'backend: %s\n' "${ACQ_RESOLVED_BACKEND:-msb}" > "$config_file"
+      # Write only the backend key, preserving any other config (extra_kits,
+      # scope_github_token) written by `acq configure` (ADR-0031).
+      _acq_config_write_field backend "${ACQ_RESOLVED_BACKEND:-msb}"
       echo "  Wrote default backend to ${config_file}." >&2
       ;;
     *)
@@ -2661,3 +2881,219 @@ acq_print_doctor() {
       ;;
   esac
 }
+
+# ============================================================================
+# Interactive configuration (`acq configure`; ADR-0031)
+# ============================================================================
+
+# _acq_configure_show_current — print the current durable configuration
+# (config.yaml) to stderr, so `acq configure` opens by showing what is in effect.
+_acq_configure_show_current() {
+  local cfg backend extras scope
+  cfg=$(_acq_config_file)
+  backend=$(_acq_config_read_field backend)
+  extras=$(_acq_config_read_field extra_kits)
+  scope=$(_acq_config_read_field scope_github_token)
+  echo "acq: current configuration (${cfg}):" >&2
+  echo "      default backend:    ${backend:-<auto-detect>}" >&2
+  echo "      extra kits:         ${extras:-<none>}" >&2
+  echo "      scope GitHub token: ${scope:-no}" >&2
+  echo "" >&2
+}
+
+# acq_configure — the interactive configuration flow. Presents the opt-in kit
+# catalog as a multiselect (pre-checked from the current config), then a confirm
+# for the GitHub-token-scoping default, and persists both to config.yaml
+# (preserving the `backend:` key). Non-interactive callers keep the current
+# config unchanged (the widgets fail-open to defaults) and only re-print it.
+#
+# The kit selection is stored as a whitespace-separated list of the CHOSEN opt-in
+# kit NAMES (e.g. "openchamber paseo") under extra_kits:, not the fully-expanded
+# git refs — the ref is rebuilt from PATTERNS_KIT_REF at apply time so a later pin
+# bump moves configured kits forward automatically. A user's own custom refs (set
+# via ACQ_EXTRA_KITS) are layered separately and are not managed here.
+acq_configure() {
+  _acq_configure_show_current
+
+  # Non-interactive (CI / piped / ACQ_NO_PROMPT): make NO changes — just show the
+  # current config above and return. Writing here would clobber a hand-edited or
+  # previously-configured file with the widget defaults.
+  if ! _acq_prompt_interactive; then
+    echo "acq: non-interactive; configuration unchanged." >&2
+    echo "      Run 'acq configure' from a terminal to change kits/token scoping." >&2
+    return 0
+  fi
+
+  local n="${#ACQ_OPTIN_KIT_NAMES[@]}"
+  if [ "$n" -eq 0 ]; then
+    echo "acq: no opt-in kits are available to configure." >&2
+    return 0
+  fi
+
+  # Which opt-in kits are already selected (from config), as a set of names.
+  local current_extras selected_names=""
+  current_extras=$(_acq_config_read_field extra_kits)
+
+  # Build the picker's argument list: the built-in kits FIRST as frozen
+  # ("always applied") rows, then the toggleable opt-in kits. The defaults CSV
+  # is RELATIVE to the toggleable block (index 1 = first opt-in kit), matching
+  # the multiselect contract, so it is unaffected by the number of locked rows.
+  local args=() defaults="" i name desc
+  local locked_n="${#ACQ_KIT_NAMES[@]}"
+  i=1
+  while [ "$i" -le "$locked_n" ]; do
+    args+=("${ACQ_KIT_NAMES[$((i-1))]}" "${ACQ_KIT_DESCS[$((i-1))]}")
+    i=$((i + 1))
+  done
+  i=1
+  while [ "$i" -le "$n" ]; do
+    name="${ACQ_OPTIN_KIT_NAMES[$((i-1))]}"
+    desc="${ACQ_OPTIN_KIT_DESCS[$((i-1))]}"
+    args+=("$name" "$desc")
+    # Pre-check if this kit name appears in the configured extras (word match).
+    case " $current_extras " in *" $name "*) defaults="${defaults:+$defaults,}$i" ;; esac
+    i=$((i + 1))
+  done
+
+  # Run the picker in-process (NOT via $(...)) so the shared scripted-input
+  # cursor advances into the token-scoping confirm below; read the result from
+  # the _ACQ_PROMPT_SELECTION global. Chosen indices are relative to the opt-in
+  # block, so the index→name mapping below is unchanged by the frozen rows.
+  local chosen
+  acq_prompt_multiselect "$locked_n" "$defaults" "${args[@]}" >/dev/null
+  chosen="$_ACQ_PROMPT_SELECTION"
+
+  # CANCELLED → leave config untouched.
+  if [ "$chosen" = "CANCELLED" ]; then
+    return 0
+  fi
+
+  # Map chosen indices back to kit names.
+  local idx
+  for idx in $chosen; do
+    case "$idx" in
+      ''|*[!0-9]*) continue ;;
+    esac
+    if [ "$idx" -ge 1 ] && [ "$idx" -le "$n" ]; then
+      name="${ACQ_OPTIN_KIT_NAMES[$((idx-1))]}"
+      selected_names="${selected_names:+$selected_names }$name"
+    fi
+  done
+
+  # Persist the kit selection (empty removes the key).
+  _acq_config_write_field extra_kits "$selected_names"
+
+  # GitHub-token-scoping default.
+  local scope_current scope_default
+  scope_current=$(_acq_config_read_field scope_github_token)
+  case "$scope_current" in yes|y|Y) scope_default="yes" ;; *) scope_default="no" ;; esac
+  if acq_prompt_confirm "Scope a per-sandbox GitHub token by default (on create)?" "$scope_default"; then
+    _acq_config_write_field scope_github_token yes
+  else
+    _acq_config_write_field scope_github_token no
+  fi
+
+  echo "" >&2
+  echo "acq: configuration saved to $(_acq_config_file)." >&2
+  echo "      extra kits:         ${selected_names:-<none>}" >&2
+  return 0
+}
+
+# maybe_first_run_configure — on first run (no config.yaml yet) and interactive,
+# offer to run `acq configure` once. Declining still writes a minimal config
+# (an empty scope_github_token line is avoided; we write the resolved backend if
+# known, else touch the file) so the offer never repeats. Fully skipped when
+# non-interactive (CI / piped) — fail-open, preserving today's behavior.
+maybe_first_run_configure() {
+  local cfg dir
+  cfg=$(_acq_config_file)
+  [ -f "$cfg" ] && return 0        # already configured (or previously offered)
+  _acq_prompt_interactive || return 0   # non-interactive: skip silently
+
+  echo "acq: looks like this is your first run — let's set up your kits." >&2
+  echo "      (You can re-run this anytime with 'acq configure'.)" >&2
+  echo "" >&2
+  if acq_prompt_confirm "Configure extra kits and token scoping now?" "yes"; then
+    acq_configure
+  else
+    # Write a minimal config so the first-run offer does not repeat. Prefer the
+    # resolved backend if one is known; otherwise create an empty file.
+    if [ -n "${ACQ_RESOLVED_BACKEND:-}" ]; then
+      _acq_config_write_field backend "$ACQ_RESOLVED_BACKEND"
+    else
+      dir=$(dirname "$cfg")
+      ( umask 077; mkdir -p "$dir" && : > "$cfg" ) 2>/dev/null || true
+      chmod 700 "$dir" 2>/dev/null || true
+      chmod 600 "$cfg" 2>/dev/null || true
+    fi
+    echo "acq: skipped. Run 'acq configure' anytime to change kits/token scoping." >&2
+  fi
+  return 0
+}
+
+# create_time_kit_picker — at `acq create`/`run` (fresh create only), offer the
+# opt-in kit picker PRE-POPULATED from the configured global defaults, so a user
+# can enable/disable a kit for THIS sandbox without changing the global default.
+# The selection is folded into ACQ_EXTRA_KITS for this invocation (as fully-
+# expanded refs), which flows through _build_kit_list and is persisted PER-SANDBOX
+# by the existing acq_cli_kits_write path (ADR-0017) — reloaded on resume by
+# acq_cli_kits_load. No global config is written here (that is `acq configure`).
+#
+# Fail-open: non-interactive (CI / piped) makes no prompt and simply lets the
+# configured defaults apply via _acq_apply_configured_extra_kits (already called
+# before provisioning). Idempotent per process.
+_ACQ_CREATE_PICKER_DONE=""
+create_time_kit_picker() {
+  [ -z "$_ACQ_CREATE_PICKER_DONE" ] || return 0
+  _ACQ_CREATE_PICKER_DONE=1
+
+  # Only prompt interactively; otherwise the configured defaults already applied.
+  _acq_prompt_interactive || return 0
+
+  local n="${#ACQ_OPTIN_KIT_NAMES[@]}"
+  [ "$n" -gt 0 ] || return 0
+
+  # Defaults = the configured global extra_kits (kit NAMES). An env-supplied
+  # ACQ_EXTRA_KITS is authoritative and NOT re-prompted (env > interactive).
+  [ -z "${ACQ_EXTRA_KITS_FROM_ENV:-}" ] || return 0
+
+  local configured args=() defaults="" i name desc
+  local locked_n="${#ACQ_KIT_NAMES[@]}"
+  configured=$(_acq_config_read_field extra_kits)
+  # Built-in kits first as frozen rows (consistent with `acq configure`).
+  i=1
+  while [ "$i" -le "$locked_n" ]; do
+    args+=("${ACQ_KIT_NAMES[$((i-1))]}" "${ACQ_KIT_DESCS[$((i-1))]}")
+    i=$((i + 1))
+  done
+  i=1
+  while [ "$i" -le "$n" ]; do
+    name="${ACQ_OPTIN_KIT_NAMES[$((i-1))]}"
+    desc="${ACQ_OPTIN_KIT_DESCS[$((i-1))]}"
+    args+=("$name" "$desc")
+    case " $configured " in *" $name "*) defaults="${defaults:+$defaults,}$i" ;; esac
+    i=$((i + 1))
+  done
+
+  echo "acq: extra kits for this sandbox (defaults from 'acq configure'):" >&2
+  # In-process (not $(...)) so the selection lands in _ACQ_PROMPT_SELECTION.
+  local chosen
+  acq_prompt_multiselect "$locked_n" "$defaults" "${args[@]}" >/dev/null
+  chosen="$_ACQ_PROMPT_SELECTION"
+  [ "$chosen" = "CANCELLED" ] && return 0
+
+  # Map chosen indices → fully-expanded kit refs, and set ACQ_EXTRA_KITS for this
+  # invocation (replacing the configured-default application, which we override
+  # deliberately: the picker's result is authoritative for this create).
+  local refs="" idx
+  for idx in $chosen; do
+    case "$idx" in ''|*[!0-9]*) continue ;; esac
+    if [ "$idx" -ge 1 ] && [ "$idx" -le "$n" ]; then
+      name="${ACQ_OPTIN_KIT_NAMES[$((idx-1))]}"
+      refs="${refs:+$refs }$(_acq_optin_kit_ref "$name")"
+    fi
+  done
+  ACQ_EXTRA_KITS="$refs"
+  acq_debug "create-picker: ACQ_EXTRA_KITS set to: $refs"
+  return 0
+}
diff --git a/acq.backends/prompt.sh b/acq.backends/prompt.sh
new file mode 100644
index 00000000..3ab996cc
--- /dev/null
+++ b/acq.backends/prompt.sh
@@ -0,0 +1,444 @@
+#!/bin/bash
+#
+# acq.backends/prompt.sh — TTY-aware interactive prompt widgets for acq
+#
+# Sourced by common.sh (next to progress.sh). Provides a small, dependency-free
+# set of interactive widgets so `acq configure` (and the create-time picker) can
+# offer a friendly, colorful selection UI — modeled on the multiselect installers
+# users already like — WITHOUT pinning a TUI dependency (gum/fzf/whiptail). See
+# ADR-0031 and issue GSA-TTS/agentic-coding-quickstart#499.
+#
+# Two public functions:
+#
+#   acq_prompt_multiselect LOCKED_N DEFAULTS_CSV LABEL_1 DESC_1 [LABEL_2 DESC_2 ...]
+#       Present a checkbox list of items. The FIRST LOCKED_N items are shown as
+#       "frozen" rows: always checked, dimmed, tagged "(always applied)", skipped
+#       by the cursor, never toggleable, and never included in the result. The
+#       remaining items are the toggleable rows. DEFAULTS_CSV is a comma-separated
+#       list of 1-based indices — RELATIVE TO THE TOGGLEABLE BLOCK (so index 1 is
+#       the first toggleable item, regardless of LOCKED_N) — pre-checked on entry
+#       (empty = none). Interactive: the user moves with the arrow keys (or j/k),
+#       toggles with SPACE, confirms with ENTER, aborts with q/ESC. On confirm,
+#       echoes the CHOSEN indices (also relative to the toggleable block) as a
+#       space-separated list on STDOUT (empty line = nothing chosen; "CANCELLED"
+#       on abort). All chrome is written to STDERR so a caller can capture the
+#       selection cleanly. Pass LOCKED_N=0 for a plain, all-toggleable list.
+#
+#   acq_prompt_confirm PROMPT DEFAULT        (DEFAULT = yes|no)
+#       A colorized [Y/n] / [y/N] confirm. Returns 0 for yes, 1 for no. The
+#       default is used on a bare ENTER and in every non-interactive path.
+#
+# DESIGN — why a tiny in-repo helper and not a library (mirrors progress.sh):
+#   acq is a thin, dependency-light wrapper the user clones and runs; pulling in
+#   a selector package would add a pinned, CVE-scanned, license-checked host
+#   dependency for cosmetic input — disproportionate and contrary to the "one
+#   clone, no extra deps" onboarding this repo provides. Mature installers
+#   hand-roll the same handful of escape sequences.
+#
+# SAFETY / CI:
+#   - Interactivity is gated on STDIN being a TTY (`[ -t 0 ]`). Color is gated
+#     independently on STDOUT-for-chrome (STDERR here) being a TTY (`[ -t 2 ]`),
+#     matching install.sh's `[ -t 1 ]` model but for our stderr chrome stream.
+#   - ACQ_NO_PROMPT (or ACQ_NO_PROGRESS) forces the non-interactive path.
+#   - Non-interactive ALWAYS takes the supplied defaults and never blocks, so CI
+#     and piped runs behave exactly as before.
+#   - ACQ_PROMPT_TEST_INPUT feeds a scripted keystroke/answer string for the
+#     offline test harness (mirrors ACQ_SECRET_TEST_VALUE), so the widgets are
+#     testable without a real terminal.
+#   - Caller-supplied labels are sanitized of control bytes before display, so an
+#     untrusted kit description can't inject terminal escapes.
+
+# _acq_prompt_sanitize TEXT — strip raw terminal control bytes from caller data,
+# so a label/description can never inject raw escapes. Keep valid UTF-8 intact;
+# raw C1 bytes are invalid UTF-8 and are dropped by iconv when available.
+_acq_prompt_sanitize() {
+  if command -v iconv >/dev/null 2>&1; then
+    { printf '%s' "$*" | iconv -f UTF-8 -t UTF-8 -c || true; } \
+      | LC_ALL=C awk '{ gsub(/\302[\200-\237]/, ""); printf "%s", $0 }' \
+      | LC_ALL=C tr -d '\000-\037\177'
+  else
+    printf '%s' "$*" | LC_ALL=C tr -d '\000-\037\177'
+  fi
+}
+
+# _acq_prompt_interactive — 0 (true) when we may run an interactive widget:
+# stdin is a TTY AND the user has not opted out. When ACQ_PROMPT_TEST_INPUT is
+# set we ALSO treat the session as interactive (the harness drives the keys),
+# so the widget logic itself is exercised offline.
+_acq_prompt_interactive() {
+  if [ -n "${ACQ_PROMPT_TEST_INPUT:-}" ]; then
+    return 0
+  fi
+  [ -z "${ACQ_NO_PROMPT:-}" ] || return 1
+  [ -z "${ACQ_NO_PROGRESS:-}" ] || return 1
+  [ -t 0 ] || return 1
+  return 0
+}
+
+# _acq_prompt_color — 0 (true) when we may emit SGR color on the chrome stream
+# (stderr). Matches install.sh's TTY gate, but for fd 2. Suppressed for the test
+# harness so assertions match plain text.
+_acq_prompt_color() {
+  [ -z "${ACQ_PROMPT_TEST_INPUT:-}" ] || return 1
+  [ -t 2 ] || return 1
+  return 0
+}
+
+# _acq_prompt_term_cols — best-effort terminal width (columns). Falls back to 80
+# when it can't be determined (non-TTY, no COLUMNS, no tput). Used to keep each
+# rendered row on exactly ONE physical line: the redraw math moves the cursor up
+# by the row count, so a row that soft-wraps to a second line would desync the
+# repaint (the classic "row duplicates and pushes others down" artifact).
+_acq_prompt_term_cols() {
+  local c=""
+  if [ -n "${COLUMNS:-}" ]; then
+    c="$COLUMNS"
+  elif command -v tput >/dev/null 2>&1; then
+    c=$(tput cols 2>/dev/null)
+  fi
+  case "$c" in
+    ''|*[!0-9]*) c=80 ;;
+  esac
+  [ "$c" -ge 20 ] || c=80
+  printf '%s' "$c"
+}
+
+# _acq_prompt_fit PLAIN MAXCOLS — echo PLAIN truncated to at most MAXCOLS display
+# columns, appending a single-column ellipsis '…' when truncated. PLAIN MUST be
+# free of escape sequences (callers colorize AFTER fitting). This uses byte/char
+# length as a proxy for width — adequate here because all labels/descriptions are
+# ASCII plus the odd box char, and it guarantees the printed cell never exceeds
+# the terminal width, which is what keeps the no-wrap invariant.
+_acq_prompt_fit() {
+  local s="$1" max="$2"
+  # Character count (locale-aware via ${#s} in bash). If it fits, return as-is.
+  if [ "${#s}" -le "$max" ]; then
+    printf '%s' "$s"
+    return 0
+  fi
+  # Reserve one column for the ellipsis.
+  local keep=$((max - 1))
+  [ "$keep" -lt 0 ] && keep=0
+  printf '%s…' "${s:0:keep}"
+}
+
+# Populate B/R/YEL/GRN/RED/DIM/CYAN for the duration of a widget. Mirrors the
+# install.sh palette (B/R/YEL/GRN/RED) plus a dim + cyan accent for the cursor
+# row. Empty strings when color is disabled, so every printf is color-safe.
+_acq_prompt_set_colors() {
+  if _acq_prompt_color; then
+    _P_B=$(printf '\033[1m');  _P_R=$(printf '\033[0m')
+    _P_YEL=$(printf '\033[33m'); _P_GRN=$(printf '\033[32m'); _P_RED=$(printf '\033[31m')
+    _P_DIM=$(printf '\033[2m'); _P_CYAN=$(printf '\033[36m')
+  else
+    _P_B=""; _P_R=""; _P_YEL=""; _P_GRN=""; _P_RED=""; _P_DIM=""; _P_CYAN=""
+  fi
+}
+
+# _acq_prompt_read_key — read a single logical keypress and store the normalized
+# token in the global _ACQ_PROMPT_KEY (rather than echoing it), so the caller can
+# invoke it WITHOUT a command substitution. That matters for the scripted test
+# path: a `$(...)` subshell would discard the advance of _ACQ_PROMPT_TEST_POS,
+# so a substitution-based reader replays the first key forever. The token is one
+# of UP DOWN LEFT RIGHT SPACE ENTER QUIT, or a literal char.
+#
+# When ACQ_PROMPT_TEST_INPUT is set, keys are consumed from that string one token
+# at a time via _ACQ_PROMPT_TEST_POS; tokens there may be the literal words
+# UP/DOWN/SPACE/ENTER/QUIT (whitespace-separated) OR single chars.
+_ACQ_PROMPT_TEST_POS=0
+_ACQ_PROMPT_KEY=""
+_acq_prompt_read_key() {
+  _ACQ_PROMPT_KEY=""
+  if [ -n "${ACQ_PROMPT_TEST_INPUT:-}" ]; then
+    # Tokenized scripted input: split on whitespace, emit the next token.
+    local toks
+    # shellcheck disable=SC2206  # deliberate word-split of the scripted input
+    toks=(${ACQ_PROMPT_TEST_INPUT})
+    if [ "$_ACQ_PROMPT_TEST_POS" -ge "${#toks[@]}" ]; then
+      _ACQ_PROMPT_KEY='ENTER'   # exhausted script → confirm, so a test can never hang
+      return 0
+    fi
+    _ACQ_PROMPT_KEY="${toks[$_ACQ_PROMPT_TEST_POS]}"
+    _ACQ_PROMPT_TEST_POS=$((_ACQ_PROMPT_TEST_POS + 1))
+    return 0
+  fi
+
+  local k rest
+  IFS= read -rsn1 k 2>/dev/null || { _ACQ_PROMPT_KEY='QUIT'; return 0; }
+  case "$k" in
+    '')      _ACQ_PROMPT_KEY='ENTER'; return 0 ;;   # Enter yields empty with -n1
+    ' ')     _ACQ_PROMPT_KEY='SPACE'; return 0 ;;
+    q|Q)     _ACQ_PROMPT_KEY='QUIT';  return 0 ;;
+    j|J)     _ACQ_PROMPT_KEY='DOWN';  return 0 ;;
+    k|K)     _ACQ_PROMPT_KEY='UP';    return 0 ;;
+    $'\033')
+      # Possible CSI sequence: read up to two more bytes non-blocking.
+      IFS= read -rsn2 -t 1 rest 2>/dev/null || rest=""
+      case "$rest" in
+        '[A') _ACQ_PROMPT_KEY='UP' ;;
+        '[B') _ACQ_PROMPT_KEY='DOWN' ;;
+        '[C') _ACQ_PROMPT_KEY='RIGHT' ;;
+        '[D') _ACQ_PROMPT_KEY='LEFT' ;;
+        *)    _ACQ_PROMPT_KEY='QUIT' ;;   # bare ESC (or unknown) → abort
+      esac
+      return 0
+      ;;
+    *) _ACQ_PROMPT_KEY="$k"; return 0 ;;
+  esac
+}
+
+# _acq_prompt_in_list NEEDLE HAYSTACK... — 0 if NEEDLE is one of the remaining
+# args. Used to test membership in the space-separated "checked" set.
+_acq_prompt_in_list() {
+  local needle="$1"; shift
+  local x
+  for x in "$@"; do
+    [ "$x" = "$needle" ] && return 0
+  done
+  return 1
+}
+
+# acq_prompt_multiselect LOCKED_N DEFAULTS_CSV LABEL DESC [LABEL DESC ...]
+# See the header for the full contract. The chosen indices (relative to the
+# toggleable block) are placed in the global _ACQ_PROMPT_SELECTION (space-
+# separated; "CANCELLED" on abort) AND echoed on stdout. Prefer the GLOBAL when
+# composing widgets in one process (e.g. acq_configure): a `$(...)` capture forks
+# a subshell, which would discard the shared scripted-input cursor advance and
+# desync a following acq_prompt_confirm.
+_ACQ_PROMPT_SELECTION=""
+acq_prompt_multiselect() {
+  _ACQ_PROMPT_SELECTION=""
+  local locked_n="${1:-0}"; shift || true
+  local defaults_csv="${1:-}"; shift || true
+  case "$locked_n" in ''|*[!0-9]*) locked_n=0 ;; esac
+
+  # Collect items into parallel index/label/desc arrays (bash 3.2 safe). Rows
+  # 1..locked_n are frozen (always-applied); rows locked_n+1..n are toggleable.
+  local labels=() descs=() n=0
+  while [ "$#" -gt 0 ]; do
+    labels+=("$(_acq_prompt_sanitize "${1:-}")"); shift || true
+    descs+=("$(_acq_prompt_sanitize "${1:-}")"); shift || true
+    n=$((n + 1))
+  done
+  [ "$n" -gt 0 ] || { _ACQ_PROMPT_SELECTION=""; printf '\n'; return 0; }
+  [ "$locked_n" -le "$n" ] || locked_n="$n"
+  local first_toggle=$((locked_n + 1))   # absolute index of the first toggleable row
+
+  # Seed the checked set (ABSOLUTE indices) from DEFAULTS_CSV, whose values are
+  # RELATIVE to the toggleable block — so add locked_n to map them to absolute.
+  local checked="" idx abs
+  local _oldifs="$IFS"; IFS=','
+  # shellcheck disable=SC2086  # intentional split on comma
+  set -- $defaults_csv
+  IFS="$_oldifs"
+  for idx in "$@"; do
+    case "$idx" in
+      ''|*[!0-9]*) : ;;   # skip empties / non-numeric
+      *)
+        abs=$((idx + locked_n))
+        [ "$abs" -ge "$first_toggle" ] && [ "$abs" -le "$n" ] && checked="$checked $abs"
+        ;;
+    esac
+  done
+
+  # Non-interactive: emit the defaults verbatim (relative indices) without chrome.
+  if ! _acq_prompt_interactive; then
+    _ACQ_PROMPT_SELECTION="$(_acq_prompt_rel_indices "$locked_n" "$checked")"
+    printf '%s\n' "$_ACQ_PROMPT_SELECTION"
+    return 0
+  fi
+
+  _acq_prompt_set_colors
+  # A standalone multiselect starts a fresh scripted-input read. (acq_configure
+  # composes multiselect+confirm in one flow and relies on the SHARED cursor, but
+  # it does not pre-seed the cursor either — the first widget in a process resets
+  # it here, and the following confirm continues from where this left off.)
+  _ACQ_PROMPT_TEST_POS=0
+  # Cursor starts on the first toggleable row (locked rows are display-only). If
+  # there are no toggleable rows, cursor stays at first_toggle (== n+1) and the
+  # only actions are ENTER/QUIT.
+  local cursor="$first_toggle" key i mark line plain cols
+  # Column budget: every row must fit on ONE physical line or the up-by-N-rows
+  # repaint desyncs (a wrapped row visually duplicates and shoves others down).
+  cols=$(_acq_prompt_term_cols)
+
+  # Hide the cursor for the duration and ensure it is restored on any exit path.
+  local _prior_int _prior_term
+  _prior_int=$(trap -p INT); _prior_term=$(trap -p TERM)
+  # shellcheck disable=SC2064
+  trap 'printf "\033[?25h" >&2; eval "${_prior_int#trap -- }" 2>/dev/null || true; trap - INT; kill -s INT $$' INT
+  [ -z "${ACQ_PROMPT_TEST_INPUT:-}" ] && printf '\033[?25l' >&2
+
+  local rendered=0
+  while :; do
+    # Repaint: move the cursor up over the previously rendered block (if any),
+    # then redraw every row. Header is drawn once above the block.
+    if [ "$rendered" -gt 0 ]; then
+      printf '\033[%dA' "$rendered" >&2
+    else
+      # Header is printed ONCE, above the repainted block, so the up-by-N repaint
+      # never touches it. Fit it to one physical line too (a wrapped header would
+      # otherwise shift everything below it by the wrap count).
+      local _hdr
+      _hdr=$(_acq_prompt_fit "? Select kits (dimmed rows are always applied · ↑/↓ move · SPACE toggle · ENTER confirm · q cancel)" "$cols")
+      printf '%s%s%s\n' "$_P_B" "$_hdr" "$_P_R" >&2
+    fi
+    i=1
+    while [ "$i" -le "$n" ]; do
+      # Assemble each row as ONE plain string (checkbox + label + description
+      # [+ tag]), fit it to the terminal width so it never soft-wraps, THEN wrap
+      # the whole thing in a single color span. Fitting the plain text (color
+      # codes are zero-width) is what keeps every row to exactly one physical
+      # line — the invariant the up-by-N repaint depends on. A single span per
+      # row (rather than per-field tinting) keeps that guarantee simple and
+      # avoids stray attributes bleeding across a truncation boundary.
+      if [ "$i" -le "$locked_n" ]; then
+        plain="  [x] ${labels[$((i-1))]}  ${descs[$((i-1))]} (always applied)"
+        line="${_P_DIM}$(_acq_prompt_fit "$plain" "$cols")${_P_R}"
+      else
+        if _acq_prompt_in_list "$i" $checked; then mark="[x]"; else mark="[ ]"; fi
+        if [ "$i" -eq "$cursor" ]; then
+          plain="❯ ${mark} ${labels[$((i-1))]}  ${descs[$((i-1))]}"
+          line="${_P_CYAN}${_P_B}$(_acq_prompt_fit "$plain" "$cols")${_P_R}"
+        else
+          plain="  ${mark} ${labels[$((i-1))]}  ${descs[$((i-1))]}"
+          if [ "$mark" = "[x]" ]; then
+            line="${_P_GRN}$(_acq_prompt_fit "$plain" "$cols")${_P_R}"
+          else
+            line="$(_acq_prompt_fit "$plain" "$cols")"
+          fi
+        fi
+      fi
+      # Clear the line first (\033[K) so a shorter repaint can't leave residue.
+      printf '\033[K%s\n' "$line" >&2
+      i=$((i + 1))
+    done
+    rendered="$n"
+
+    _acq_prompt_read_key
+    key="$_ACQ_PROMPT_KEY"
+    case "$key" in
+      UP)
+        # Move within the toggleable block only; wrap top<->bottom. No-op when
+        # there are no toggleable rows.
+        if [ "$first_toggle" -le "$n" ]; then
+          cursor=$((cursor - 1)); [ "$cursor" -lt "$first_toggle" ] && cursor="$n"
+        fi
+        ;;
+      DOWN)
+        if [ "$first_toggle" -le "$n" ]; then
+          cursor=$((cursor + 1)); [ "$cursor" -gt "$n" ] && cursor="$first_toggle"
+        fi
+        ;;
+      SPACE)
+        # Toggle only when the cursor is on a real toggleable row (guard locked).
+        if [ "$cursor" -ge "$first_toggle" ] && [ "$cursor" -le "$n" ]; then
+          if _acq_prompt_in_list "$cursor" $checked; then
+            local new="" c
+            for c in $checked; do [ "$c" != "$cursor" ] && new="$new $c"; done
+            checked="$new"
+          else
+            checked="$checked $cursor"
+          fi
+        fi
+        ;;
+      ENTER)
+        break
+        ;;
+      QUIT)
+        printf '\033[?25h' >&2
+        # Restore prior signal traps and abort the SELECTION (empty) — the caller
+        # treats an empty line as "keep defaults / no change".
+        eval "${_prior_int#trap -- }" 2>/dev/null || trap - INT
+        eval "${_prior_term#trap -- }" 2>/dev/null || trap - TERM
+        printf '%sacq: selection cancelled; keeping current configuration.%s\n' "$_P_DIM" "$_P_R" >&2
+        _ACQ_PROMPT_SELECTION="CANCELLED"
+        printf 'CANCELLED\n'
+        return 0
+        ;;
+      *) : ;;   # ignore any other key
+    esac
+  done
+
+  [ -z "${ACQ_PROMPT_TEST_INPUT:-}" ] && printf '\033[?25h' >&2
+  eval "${_prior_int#trap -- }" 2>/dev/null || trap - INT
+  eval "${_prior_term#trap -- }" 2>/dev/null || trap - TERM
+
+  # Emit the chosen indices (relative to the toggleable block) in ascending order.
+  _ACQ_PROMPT_SELECTION="$(_acq_prompt_rel_indices "$locked_n" "$checked")"
+  printf '%s\n' "$_ACQ_PROMPT_SELECTION"
+  return 0
+}
+
+# _acq_prompt_rel_indices LOCKED_N CHECKED_ABS — echo the checked ABSOLUTE indices
+# (a space-separated set) as ascending TOGGLEABLE-RELATIVE indices (abs-LOCKED_N),
+# dropping any that fall in the locked range. Keeps the caller's index→name map
+# stable regardless of how many rows are frozen.
+_acq_prompt_rel_indices() {
+  local locked_n="$1" checked="$2" out="" j
+  # Ascending sort is unnecessary if we scan positions in order:
+  local total=0 c
+  for c in $checked; do [ "$c" -gt "$total" ] && total="$c"; done
+  j=$((locked_n + 1))
+  while [ "$j" -le "$total" ]; do
+    _acq_prompt_in_list "$j" $checked && out="$out $((j - locked_n))"
+    j=$((j + 1))
+  done
+  printf '%s' "$(printf '%s' "$out" | sed 's/^ *//')"
+}
+
+# acq_prompt_confirm PROMPT DEFAULT  (DEFAULT = yes|no) — colorized [Y/n]/[y/N].
+# Returns 0 for yes, 1 for no. Bare ENTER and every non-interactive path use the
+# default. Honors ACQ_PROMPT_TEST_INPUT (first token: y/yes → yes, else no).
+acq_prompt_confirm() {
+  local prompt default="${2:-no}"
+  prompt=$(_acq_prompt_sanitize "${1:-Proceed?}")
+
+  local hint
+  case "$default" in
+    yes|y|Y) default="yes"; hint="[Y/n]" ;;
+    *)       default="no";  hint="[y/N]" ;;
+  esac
+
+  # Scripted test input takes precedence (the harness drives the answer). Two
+  # shapes are supported so tests can drive both a standalone confirm AND a
+  # confirm that follows a multiselect in one flow:
+  #   - a SINGLE-token script ("y"/"n") is a standalone confirm answer, consumed
+  #     without advancing the shared multiselect cursor (so repeated standalone
+  #     confirms in one process each see their own single token);
+  #   - a MULTI-token script is a whole flow (multiselect keys THEN the confirm
+  #     answer): consume the NEXT token from the shared cursor so the confirm
+  #     picks up where the multiselect left off.
+  # A recognized y/n token decides; anything else → default.
+  if [ -n "${ACQ_PROMPT_TEST_INPUT:-}" ]; then
+    local _toks answer
+    # shellcheck disable=SC2206  # deliberate word-split of the scripted input
+    _toks=(${ACQ_PROMPT_TEST_INPUT})
+    if [ "${#_toks[@]}" -le 1 ]; then
+      answer="${_toks[0]:-}"
+    else
+      _acq_prompt_read_key
+      answer="$_ACQ_PROMPT_KEY"
+    fi
+    case "$answer" in
+      y|Y|yes|YES) return 0 ;;
+      n|N|no|NO)   return 1 ;;
+      *)           [ "$default" = "yes" ] && return 0 || return 1 ;;
+    esac
+  fi
+
+  # Non-interactive (CI / piped / opted-out): take the default, never block.
+  if ! _acq_prompt_interactive; then
+    [ "$default" = "yes" ] && return 0 || return 1
+  fi
+
+  _acq_prompt_set_colors
+  local ans=""
+  printf '%s%s?%s %s %s%s%s ' "$_P_B" "$_P_GRN" "$_P_R" "$prompt" "$_P_DIM" "$hint" "$_P_R" >&2
+  read -r ans 2>/dev/null || ans=""
+  case "$ans" in
+    y|Y|yes|YES) return 0 ;;
+    n|N|no|NO)   return 1 ;;
+    *)           [ "$default" = "yes" ] && return 0 || return 1 ;;
+  esac
+}
diff --git a/docs/CONCEPTS.md b/docs/CONCEPTS.md
index 8f54ad42..f02ec909 100644
--- a/docs/CONCEPTS.md
+++ b/docs/CONCEPTS.md
@@ -191,6 +191,8 @@ repository for details.
 `acq` applies a fixed set of built-in kits, pinned to a commit of the patterns
 repo. To customize:
 
+- **Pick opt-in kits interactively:** run `acq configure` (see
+  [Interactive setup: `acq configure`](#interactive-setup-acq-configure)).
 - **Add your own kits on every run:** see [Advanced: extra kits](#advanced-extra-kits).
 - **Change USAi models / provider config, rules, or skills:** contribute to the
   kits in the
@@ -200,6 +202,39 @@ repo. To customize:
 - **Adopt newer kit versions:** bump `PATTERNS_KIT_REF` near the top of
   `acq.backends/common.sh`.
 
+### Interactive setup: `acq configure`
+
+`acq configure` opens a small, colorful interactive picker (no extra tools to
+install) that lets you choose which **opt-in** kits to enable and set the default
+answer for the per-sandbox GitHub-token-scoping prompt. Choices persist to
+`~/.config/acq/config.yaml`, so you set them once instead of repeating `--kit`
+flags on every run.
+
+```text
+? Select kits (dimmed rows are always applied · ↑/↓ move · SPACE toggle · ENTER confirm · q cancel)
+  [x] zscaler-ca-certificate   Zscaler/corporate CA trust … (always applied)
+  [x] usai-provider            USAi provider + model config … (always applied)
+  [x] agentic-coding-playbook  Federal agent rules and skills … (always applied)
+  [x] git-ssh-sign             SSH-based git commit signing … (always applied)
+❯ [x] openchamber              Browser UI for OpenCode alongside the terminal TUI
+  [ ] paseo                    Self-hosted Paseo browser web UI for coding agents
+```
+
+- The **four built-in kits** (`zscaler-ca-certificate`, `usai-provider`,
+  `agentic-coding-playbook`, `git-ssh-sign`) appear as **frozen rows** at the top
+  — always checked, dimmed, and tagged `(always applied)`. The cursor skips them
+  and they can't be toggled; the picker manages only the opt-in extras below.
+- On your **first run**, `acq` offers to run this for you. Run it again anytime
+  with `acq configure`.
+- At `acq create`, the picker is shown again **pre-populated with your saved
+  defaults**, so a single sandbox can enable or disable a kit without changing
+  the global default (the deviation is remembered for that sandbox).
+- The **GitHub-token** preference only pre-answers the scoping prompt; the
+  fine-grained token is still minted per-sandbox (see
+  [`acq github-scope`](howto/acq.md)).
+- Non-interactive/CI runs make no changes and simply print the current
+  configuration. Set `ACQ_NO_PROMPT=1` to force that behavior.
+
 ### Advanced: extra kits
 
 `acq` always applies its built-in kits. To apply **additional** kits on
@@ -210,6 +245,10 @@ whitespace-separated list of kit references (local paths or remote refs):
 export ACQ_EXTRA_KITS="./my-local-kit git+https://github.com/acme/kits.git#ref=<sha>&dir=some-kit"
 ```
 
+An explicitly-exported `ACQ_EXTRA_KITS` takes precedence over the kits saved by
+`acq configure` (env wins): the interactive picker is skipped and your env value
+is used verbatim.
+
 Extras are applied **after** the built-in kits (so they win on any overlapping
 config). They also work when re-running against an existing sandbox: adding a new
 entry and re-running `acq run <existing-sandbox>` injects just the new kit.
diff --git a/docs/adr/0031-interactive-acq-configure.md b/docs/adr/0031-interactive-acq-configure.md
new file mode 100644
index 00000000..f24ef476
--- /dev/null
+++ b/docs/adr/0031-interactive-acq-configure.md
@@ -0,0 +1,136 @@
+---
+title: "Interactive `acq configure` for extra kits and token-scoping defaults"
+status: accepted
+date: 2026-09-20
+decision_makers: ["Bret Mogilefsky"]
+category: development-process
+nist_controls: ["AC-6", "CM-6", "IA-5", "SA-15", "SR-3"]
+impact_level: low
+ato_relevance: no
+risk_treatment: n/a
+supersedes: []
+---
+
+# ADR-0031: Interactive `acq configure` for extra kits and token-scoping defaults
+
+## Context and Problem Statement
+
+`acq` always applies four built-in kits (`zscaler-ca-certificate`,
+`usai-provider`, `agentic-coding-playbook`, `git-ssh-sign`). The only levers for
+**opt-in** kits are `--kit <ref>` on `run`/`create` and the `ACQ_EXTRA_KITS` env
+var — both must be re-supplied on every invocation and neither is discoverable.
+A new user has no way to learn that opt-in community kits (`openchamber`,
+`paseo`) exist, and no way to enable one durably. Separately, per-sandbox GitHub
+token scoping (ADR-0013) surfaces only as a bare `[y/N]` nudge inside the run
+flow, with no persisted default.
+
+How should a user discover and durably configure opt-in kits and their
+token-scoping default, without adding a heavyweight TUI dependency and without
+changing the security model?
+
+## Decision Drivers
+
+- **Discoverability** — the opt-in kit catalog should be visible and
+  self-documenting, not tribal knowledge.
+- **Durability** — a choice should persist across invocations rather than being
+  re-typed each run.
+- **Right granularity** — a global default plus per-sandbox deviations matches
+  real usage (set once; override for the odd sandbox).
+- **Supply-chain minimalism (SR-3)** — the repo posture is "one clone, no extra
+  deps"; a cosmetic picker must not pin `gum`/`fzf`/`whiptail`.
+- **Least privilege (AC-6, IA-5)** — the token-scoping default must not weaken
+  ADR-0013: it sets only the *default answer* to the existing per-sandbox
+  scoping prompt; fine-grained-PAT minting stays per-sandbox.
+- **Fail-open in CI (SA-15)** — non-interactive/piped runs must behave exactly
+  as they do today (take defaults, never block).
+
+## Considered Options
+
+1. **Status quo** — keep `--kit`/`ACQ_EXTRA_KITS` only. Zero work, but leaves the
+   discoverability and durability gaps unaddressed.
+2. **A pinned TUI dependency** (`gum`/`fzf`/`whiptail`/`dialog`) driving a rich
+   selector. Nicer out of the box, but adds a CVE-scanned, license-checked host
+   dependency for purely cosmetic output — contrary to the onboarding this repo
+   exists to provide, and inconsistent with the `progress.sh` design note.
+3. **Hand-rolled interactive picker + `acq configure` + `config.yaml`
+   persistence** (chosen). A ~40-line bash multiselect modeled on the existing
+   `progress.sh`/`install.sh` conventions, a new `acq configure` command, global
+   defaults in the file that already holds `backend:`, and per-sandbox deviations
+   reusing the existing per-sandbox kit records.
+
+## Decision Outcome
+
+Chosen: **option 3**.
+
+- **New `acq.backends/prompt.sh`** — `acq_prompt_multiselect` and
+  `acq_prompt_confirm`. Stderr-only chrome, gated on an interactive TTY
+  (`[ -t 0 ]` for input, `[ -t 2 ]` for stderr color), colored with the same
+  `install.sh` SGR scheme, bash-3.2 safe, caller labels escape-sanitized (as in
+  `progress.sh`). Honors an `ACQ_NO_PROMPT` opt-out and an `ACQ_PROMPT_TEST_INPUT`
+  test hook (mirroring `ACQ_SECRET_TEST_VALUE`). Non-TTY / opted-out degrades to
+  documented defaults and never blocks.
+- **Opt-in kit catalog** — sourced from the already-pinned patterns bundle
+  (`PATTERNS_KIT_REF` / `PATTERNS_KIT_DIR`, `integrations/isolation/acq-kits/`):
+  `openchamber`, `paseo`. `prime-agent` is a skeleton at the current pin and is
+  intentionally omitted until functional. Custom refs remain available through
+  `ACQ_EXTRA_KITS` and `--kit`, but are not stored in durable config. The four
+  built-ins are shown **inline as frozen rows** at the top of the same picker —
+  always checked, dimmed, tagged
+  "(always applied)", cursor-skipped, and never toggleable — rather than in a
+  separate banner, so the full applied set reads as one list.
+- **`acq configure` command** — shows current config, runs the multiselect over
+  the opt-in catalog, then a confirm for the token-scoping default, and writes
+  the result to `config.yaml`. Auto-offered once on first run (no `config.yaml`
+  yet AND interactive), writing a minimal config so it never nags again.
+- **Config schema** — `config.yaml` gains flat keys `extra_kits:` and
+  `scope_github_token:` alongside the existing `backend:`. The single-key awk
+  parser is generalized to read/write named flat keys, preserving the existing
+  `backend:` line and the "no YAML dependency" convention. The config directory
+  and file are written private to the user, and the flat-key reader ignores
+  indented/nested YAML so hand-edited structure is not mistaken for a top-level
+  setting.
+- **`acq create`/`run`** — pre-populate the picker from the global defaults, fold
+  the selection into the existing `ACQ_EXTRA_KITS`/`ACQ_CLI_KITS` path (so it
+  flows through `_build_kit_list` → `acq_cli_kits_write`), and thereby persist
+  per-sandbox deviations in the existing per-sandbox kit record (ADR-0017),
+  reloaded on resume by `acq_cli_kits_load`.
+- **Token-scoping default** — the stored preference only pre-answers the existing
+  `advise_github_scope` prompt; `github_scope_sandbox` still mints a fine-grained
+  PAT scoped to the sandbox's repos (ADR-0013 unchanged).
+
+## Consequences
+
+**Positive**
+
+- Opt-in kits become discoverable and durable; onboarding improves with no new
+  dependency.
+- Global-default + per-sandbox-deviation granularity is achieved by reusing
+  existing config and per-sandbox record mechanisms — minimal new surface.
+- CI/non-interactive behavior is unchanged (fail-open by construction).
+
+**Negative / trade-offs**
+
+- A hand-rolled multiselect is less capable than a real TUI library (no mouse,
+  simple key handling). Accepted per the minimalism driver.
+- `config.yaml` now carries more than one key; the awk parser is generalized but
+  remains a deliberately small, flat-only reader.
+
+**Compliance implications**
+
+- **AC-6 / IA-5 (least privilege, credentials):** the token-scoping preference is
+  a UI default only; no broadening of token scope. ADR-0013's per-sandbox
+  fine-grained PAT flow is authoritative.
+- **SR-3 (supply chain):** no new runtime dependency is introduced.
+- **SA-15 (development process):** covered by new offline bats tests driving the
+  prompt via `ACQ_PROMPT_TEST_INPUT` and asserting `config.yaml` round-trips and
+  non-TTY defaulting.
+
+## Links / tracking
+
+- Implements GSA-TTS/agentic-coding-quickstart#499.
+- Builds on ADR-0013 (per-sandbox GitHub token downscoping), ADR-0017 (msb
+  create-time startup + persisted CLI/extra kit refs), ADR-0010/0011 (pluggable
+  backends and neutral kits).
+- Complementary to, and distinct from, the per-repo `.acq/` config proposal in
+  GSA-TTS/agentic-coding-quickstart#232 (repo-committed config vs. user-global
+  config).
diff --git a/docs/howto/acq.md b/docs/howto/acq.md
index b1d63865..59414cdc 100644
--- a/docs/howto/acq.md
+++ b/docs/howto/acq.md
@@ -494,6 +494,30 @@ design and trust model.
 
 ---
 
+## Interactive setup: `acq configure`
+
+`acq configure` is a colorful, dependency-free interactive picker for choosing
+which **opt-in** kits to enable and the default answer for per-sandbox GitHub
+token scoping. Choices persist to `~/.config/acq/config.yaml`.
+
+```bash
+acq configure
+```
+
+- The four built-in kits are always applied; the picker only manages opt-in
+  extras (e.g. `openchamber`, `paseo`).
+- `acq` offers to run this on your first run; run it again anytime.
+- `acq create` re-shows the picker pre-filled with your saved defaults, so one
+  sandbox can deviate without changing the global default (the deviation is
+  remembered per-sandbox and re-applied on resume).
+- The token preference only pre-answers the scoping prompt — the fine-grained
+  PAT is still minted per-sandbox (`acq github-scope`).
+- Non-interactive/CI runs make no changes and just print the current config; set
+  `ACQ_NO_PROMPT=1` to force that. See
+  [ADR-0031](../adr/0031-interactive-acq-configure.md).
+
+---
+
 ## Advanced: extra kits
 
 ```bash
@@ -504,6 +528,10 @@ export ACQ_EXTRA_KITS="./my-local-kit git+https://github.com/acme/kits.git#ref=<
 export ACQ_EXTRA_KIT_SOURCES="github.com/acme/"
 ```
 
+An exported `ACQ_EXTRA_KITS` takes precedence over the kits saved by
+`acq configure` (env wins): the create-time picker is skipped and your env value
+is used verbatim.
+
 You can also apply an extra kit for a single `run`/`create` with `--kit`
 (repeatable), instead of the env var:
 
diff --git a/test/bats/135-configure.bats b/test/bats/135-configure.bats
new file mode 100644
index 00000000..11c30224
--- /dev/null
+++ b/test/bats/135-configure.bats
@@ -0,0 +1,405 @@
+#!/usr/bin/env bats
+#
+# 135-configure.bats — interactive `acq configure` + config.yaml + prompt widgets
+# (ADR-0031; issue GSA-TTS/agentic-coding-quickstart#499).
+#
+# Covers, offline (no TTY, no backend CLI, no network):
+#   - the generalized config.yaml reader/writer (multi-key, preserve-others)
+#   - the opt-in kit catalog + ref expansion
+#   - the prompt widgets driven via ACQ_PROMPT_TEST_INPUT
+#   - `acq configure` dispatch, --help, and the non-interactive fail-open path
+#   - configured-default extra-kit application with env-wins precedence
+#
+# shellcheck shell=bats
+
+setup() { acq_setup_stubs; }
+teardown() { acq_teardown_stubs; }
+
+load 'helper'
+
+# _cfg — source acq (definitions only) + the sbx adapter, so the configure/config
+# helpers are in scope for in-process assertions. Mirrors 20-backend-resolution.
+_cfg_src() {
+  # shellcheck source=acq
+  ACQ_SOURCE_ONLY=1 . "$ACQ"
+  # shellcheck source=/dev/null
+  . "${REPO_ROOT}/acq.backends/sbx.sh"
+}
+
+# ---------------------------------------------------------------------------
+# config.yaml reader / writer
+# ---------------------------------------------------------------------------
+
+@test "config: write then read a flat key round-trips" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    _acq_config_write_field backend msb
+    _acq_config_read_field backend
+  '
+  assert_success
+  assert_output 'msb'
+}
+
+@test "config: writing one key preserves the others" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    _acq_config_write_field backend msb
+    _acq_config_write_field extra_kits "openchamber paseo"
+    _acq_config_write_field scope_github_token yes
+    # Rewriting extra_kits must not disturb backend / scope.
+    _acq_config_write_field extra_kits "paseo"
+    printf "b=%s\n" "$(_acq_config_read_field backend)"
+    printf "k=%s\n" "$(_acq_config_read_field extra_kits)"
+    printf "s=%s\n" "$(_acq_config_read_field scope_github_token)"
+  '
+  assert_success
+  assert_line 'b=msb'
+  assert_line 'k=paseo'
+  assert_line 's=yes'
+}
+
+@test "config: empty value removes the key but keeps the rest" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    _acq_config_write_field backend msb
+    _acq_config_write_field extra_kits "openchamber"
+    _acq_config_write_field extra_kits ""
+    printf "b=%s\n" "$(_acq_config_read_field backend)"
+    printf "k=[%s]\n" "$(_acq_config_read_field extra_kits)"
+  '
+  assert_success
+  assert_line 'b=msb'
+  assert_line 'k=[]'
+}
+
+@test "config: an unsafe key name is rejected (fail closed)" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    set +e
+    _acq_config_write_field "bad key" value ; echo "write-rc=$?"
+    _acq_config_read_field "bad/key" ; echo "read-rc=$?"
+    true
+  '
+  assert_success
+  assert_line 'write-rc=1'
+  assert_line 'read-rc=0'
+}
+
+@test "config: reader ignores nested YAML and uses last top-level duplicate" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'extra_kits: openchamber\nsome_block:\n  extra_kits: nested-evil\nextra_kits: paseo\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    _acq_config_read_field extra_kits
+  '
+  assert_success
+  assert_output 'paseo'
+}
+
+@test "config: reader tolerates inline comments and quoted scalars" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg-comments"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'extra_kits: "openchamber # browser UI"\nscope_github_token: "yes"\nbackend: '\''msb'\''\nlabel: don'\''t # plain scalar comment\nplain_kits: openchamber # browser UI\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    printf "k=%s\n" "$(_acq_config_read_field extra_kits)"
+    printf "s=%s\n" "$(_acq_config_read_field scope_github_token)"
+    printf "b=%s\n" "$(_acq_config_read_field backend)"
+    printf "l=%s\n" "$(_acq_config_read_field label)"
+    printf "p=%s\n" "$(_acq_config_read_field plain_kits)"
+  '
+  assert_success
+  assert_line 'k=openchamber # browser UI'
+  assert_line 's=yes'
+  assert_line 'b=msb'
+  assert_line "l=don't"
+  assert_line 'p=openchamber'
+}
+
+@test "config: writer creates private config directory and file" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg"
+  run bash -c '
+    umask 022
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    _acq_config_write_field backend msb
+    cfg="$XDG_CONFIG_HOME/acq/config.yaml"
+    dir_mode=$(stat -c %a "$(dirname "$cfg")" 2>/dev/null || stat -f %Lp "$(dirname "$cfg")" 2>/dev/null || echo "?")
+    file_mode=$(stat -c %a "$cfg" 2>/dev/null || stat -f %Lp "$cfg" 2>/dev/null || echo "?")
+    printf "dir=%s\n" "$dir_mode"
+    printf "file=%s\n" "$file_mode"
+  '
+  assert_success
+  assert_line 'dir=700'
+  assert_line 'file=600'
+}
+
+# ---------------------------------------------------------------------------
+# opt-in kit catalog + ref expansion
+# ---------------------------------------------------------------------------
+
+@test "catalog: opt-in kit ref is pinned to PATTERNS_KIT_REF/DIR" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    _acq_optin_kit_ref openchamber
+  '
+  assert_success
+  assert_output --partial 'agentic-coding-patterns.git#ref='
+  assert_output --partial 'dir=integrations/isolation/acq-kits/openchamber'
+}
+
+@test "catalog: prime-agent is intentionally NOT offered (skeleton at pin)" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    printf "%s\n" "${ACQ_OPTIN_KIT_NAMES[@]}"
+  '
+  assert_success
+  assert_line 'openchamber'
+  assert_line 'paseo'
+  refute_line 'prime-agent'
+}
+
+# ---------------------------------------------------------------------------
+# prompt widgets (driven by ACQ_PROMPT_TEST_INPUT)
+# ---------------------------------------------------------------------------
+
+@test "prompt: multiselect toggles the cursor item and returns its index" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    ACQ_PROMPT_TEST_INPUT="SPACE ENTER" \
+      acq_prompt_multiselect 0 "" "openchamber" "descA" "paseo" "descB" 2>/dev/null
+  '
+  assert_success
+  assert_output '1'
+}
+
+@test "prompt: multiselect can DOWN then toggle the second item" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    ACQ_PROMPT_TEST_INPUT="DOWN SPACE ENTER" \
+      acq_prompt_multiselect 0 "" "a" "d" "b" "d" 2>/dev/null
+  '
+  assert_success
+  assert_output '2'
+}
+
+@test "prompt: multiselect defaults pre-check, and can be toggled off" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    # default-checked index 2; move to it and toggle it off -> empty result
+    ACQ_PROMPT_TEST_INPUT="DOWN SPACE ENTER" \
+      acq_prompt_multiselect 0 "2" "a" "d" "b" "d" 2>/dev/null
+  '
+  assert_success
+  assert_output ''
+}
+
+@test "prompt: multiselect QUIT yields CANCELLED (no change sentinel)" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    ACQ_PROMPT_TEST_INPUT="QUIT" \
+      acq_prompt_multiselect 0 "1" "a" "d" "b" "d" 2>/dev/null
+  '
+  assert_success
+  assert_output 'CANCELLED'
+}
+
+@test "prompt: locked rows are frozen — cursor skips them, result excludes them" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    set +e
+    # 2 locked rows (L1,L2) then 2 toggleable (T1,T2). Cursor starts on T1.
+    # SPACE toggles T1 -> result is the toggleable-relative index 1.
+    ACQ_PROMPT_TEST_INPUT="SPACE ENTER" \
+      acq_prompt_multiselect 2 "" "L1" "d" "L2" "d" "T1" "d" "T2" "d" >/dev/null 2>&1
+    echo "one=$_ACQ_PROMPT_SELECTION"
+    # UP from T1 wraps to T2 (never onto a locked row); SPACE toggles T2 -> index 2.
+    ACQ_PROMPT_TEST_INPUT="UP SPACE ENTER" \
+      acq_prompt_multiselect 2 "" "L1" "d" "L2" "d" "T1" "d" "T2" "d" >/dev/null 2>&1
+    echo "up=$_ACQ_PROMPT_SELECTION"
+    # A default pre-check is relative to the toggleable block (2 = T2); toggle it off.
+    ACQ_PROMPT_TEST_INPUT="DOWN SPACE ENTER" \
+      acq_prompt_multiselect 2 "2" "L1" "d" "L2" "d" "T1" "d" "T2" "d" >/dev/null 2>&1
+    echo "off=$_ACQ_PROMPT_SELECTION"
+    true
+  '
+  assert_success
+  assert_line 'one=1'
+  assert_line 'up=2'
+  assert_line 'off='
+}
+
+@test "prompt: rows are fit to the terminal width (no soft-wrap desync)" {
+  # A row longer than the terminal width used to soft-wrap onto a second physical
+  # line, which desynced the up-by-N-rows repaint (rows visibly duplicated and
+  # pushed others down). Assert each rendered row's VISIBLE width is <= COLUMNS.
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    set +e
+    export COLUMNS=60
+    long="this is a deliberately very long description that exceeds sixty display columns easily"
+    ACQ_PROMPT_TEST_INPUT="SPACE ENTER" \
+      acq_prompt_multiselect 1 "" "locked-kit" "$long" "toggle-kit" "$long" 2>/tmp/acq-rows.txt >/dev/null
+    # Widest visible row, measured in CHARACTERS (wc -m, locale-aware) so the
+    # multibyte cursor/ellipsis glyphs count as one display column each — matching
+    # the widget'"'"'s own char-based fit. Strip escapes and blank lines first.
+    max=0
+    while IFS= read -r ln; do
+      w=$(printf "%s" "$ln" | LC_ALL=C.UTF-8 wc -m)
+      [ "$w" -gt "$max" ] && max="$w"
+    done < <(sed "s/\x1b\[[0-9;?]*[A-Za-z]//g" /tmp/acq-rows.txt | grep -v "^$")
+    rm -f /tmp/acq-rows.txt
+    if [ "$max" -le "$COLUMNS" ]; then echo "FIT ok ($max <= $COLUMNS)"; else echo "FIT BAD ($max > $COLUMNS)"; fi
+    true
+  '
+  assert_success
+  assert_output --partial 'FIT ok'
+}
+
+@test "prompt: confirm honors scripted y/n and the default" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    set +e
+    ACQ_PROMPT_TEST_INPUT="y" acq_prompt_confirm "ok?" "no";  echo "y=$?"
+    ACQ_PROMPT_TEST_INPUT="n" acq_prompt_confirm "ok?" "yes"; echo "n=$?"
+    ACQ_NO_PROMPT=1 acq_prompt_confirm "ok?" "yes";           echo "dy=$?"
+    ACQ_NO_PROMPT=1 acq_prompt_confirm "ok?" "no";            echo "dn=$?"
+    true
+  '
+  assert_success
+  assert_line 'y=0'
+  assert_line 'n=1'
+  assert_line 'dy=0'
+  assert_line 'dn=1'
+}
+
+@test "prompt: sanitizer strips terminal controls without mangling UTF-8" {
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    _acq_prompt_sanitize "$(printf "don\342\200\231t \342\200\246 a\033[31m\2331m\302\23332m\177b")" | od -An -tx1 | tr -d " \n"
+  '
+  assert_success
+  assert_output '646f6ee280997420e280a620615b33316d316d33326d62'
+}
+
+@test "prompt: a multi-token script drives multiselect THEN confirm in one flow" {
+  # This mirrors how acq_configure calls the widgets in-process (no subshell
+  # between them), so the shared scripted-input cursor advances across both.
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    export ACQ_PROMPT_TEST_INPUT="SPACE ENTER y"
+    # Do NOT command-substitute the multiselect (that would fork a subshell and
+    # lose the cursor advance); redirect its stdout to a file instead.
+    acq_prompt_multiselect 0 "" "a" "d" "b" "d" >/dev/null 2>&1
+    acq_prompt_confirm "scope?" "no"; echo "confirm=$?"
+    true
+  '
+  assert_success
+  assert_line 'confirm=0'
+}
+
+# ---------------------------------------------------------------------------
+# `acq configure` dispatch + help + non-interactive fail-open
+# ---------------------------------------------------------------------------
+
+@test "configure: --help documents the command" {
+  run env ACQ_BACKEND=sbx "$ACQ" configure --help
+  assert_success
+  assert_output --partial 'acq configure'
+  assert_output --partial 'ADR-0031'
+}
+
+@test "configure: help banner lists the configure verb" {
+  run env ACQ_BACKEND=sbx "$ACQ" help
+  assert_success
+  assert_output --partial 'configure'
+}
+
+@test "configure: non-interactive makes NO changes and just prints current" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg2"
+  run env ACQ_BACKEND=sbx ACQ_NO_PROMPT=1 "$ACQ" configure
+  assert_success
+  assert_output --partial 'current configuration'
+  assert_output --partial 'configuration unchanged'
+  # No config file should have been written by the non-interactive path.
+  [ ! -f "$XDG_CONFIG_HOME/acq/config.yaml" ]
+}
+
+@test "configure: interactive selection persists to config.yaml" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg3"
+  # The built-in kits render as frozen rows; the cursor starts on the first
+  # opt-in (openchamber). SPACE toggles it, ENTER confirms; the token-scoping
+  # confirm then reads the next token (n).
+  run env ACQ_BACKEND=sbx ACQ_PROMPT_TEST_INPUT="SPACE ENTER n" "$ACQ" configure
+  assert_success
+  # Built-in kits appear inline in the picker (frozen rows), not in a separate
+  # banner. The trailing "(always applied)" tag may be truncated at narrow widths,
+  # so assert on the always-present frozen row prefix + the removed banner.
+  assert_output --partial '[x] zscaler-ca-certificate'
+  refute_output --partial 'Built-in kits (always applied):'
+  run cat "$XDG_CONFIG_HOME/acq/config.yaml"
+  assert_line 'extra_kits: openchamber'
+  assert_line 'scope_github_token: no'
+}
+
+@test "configure: preserves an existing backend key when saving kits" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg4"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'backend: sbx\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  run env ACQ_BACKEND=sbx ACQ_PROMPT_TEST_INPUT="SPACE ENTER y" "$ACQ" configure
+  assert_success
+  run cat "$XDG_CONFIG_HOME/acq/config.yaml"
+  assert_line 'backend: sbx'
+  assert_line 'extra_kits: openchamber'
+  assert_line 'scope_github_token: yes'
+}
+
+# ---------------------------------------------------------------------------
+# configured-default extra-kit application + env precedence
+# ---------------------------------------------------------------------------
+
+@test "apply: configured extra_kits expand to pinned refs" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg5"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'extra_kits: openchamber paseo\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    ACQ_EXTRA_KITS=""; ACQ_EXTRA_KITS_FROM_ENV=""
+    _acq_apply_configured_extra_kits
+    printf "%s\n" "$ACQ_EXTRA_KITS"
+  '
+  assert_success
+  assert_output --partial 'dir=integrations/isolation/acq-kits/openchamber'
+  assert_output --partial 'dir=integrations/isolation/acq-kits/paseo'
+}
+
+@test "apply: unknown configured extra_kits names fail closed" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg6"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'extra_kits: openchamber git+https://evil.example/x.git#ref=abc&dir=kit\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    ACQ_EXTRA_KITS=""; ACQ_EXTRA_KITS_FROM_ENV=""
+    _acq_apply_configured_extra_kits
+  '
+  assert_failure
+  assert_output --partial "unknown kit 'git+https://evil.example/x.git#ref=abc&dir=kit'"
+}
+
+@test "apply: an env-supplied ACQ_EXTRA_KITS wins over the configured default" {
+  export XDG_CONFIG_HOME="$STUBDIR/xdg7"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'extra_kits: openchamber\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  run bash -c '
+    ACQ_SOURCE_ONLY=1 . "'"$ACQ"'" >/dev/null 2>&1
+    ACQ_EXTRA_KITS="./mine"; ACQ_EXTRA_KITS_FROM_ENV=1
+    _acq_apply_configured_extra_kits
+    printf "%s\n" "$ACQ_EXTRA_KITS"
+  '
+  assert_success
+  assert_output './mine'
+}
diff --git a/test/bats/30-dispatch-routing.bats b/test/bats/30-dispatch-routing.bats
index da8d4041..0835b5c8 100644
--- a/test/bats/30-dispatch-routing.bats
+++ b/test/bats/30-dispatch-routing.bats
@@ -166,6 +166,47 @@ _seed_usai() {
   assert [ -f "$STUBDIR/.created" ]
 }
 
+@test "create: unknown configured extra_kits fails before backend create" {
+  local proj="$STUBDIR/bad-config-kit"; mkdir -p "$proj"
+  export XDG_CONFIG_HOME="$STUBDIR/xdg"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'extra_kits: git+https://evil.example/x.git#ref=abc&dir=kit\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  mkdir -p "$STUBDIR/secrets"; printf 'sk-stored-and-bound\n' > "$STUBDIR/secrets/acq.usai"
+  seed_sbx_usai_proxy_fixture
+  rm -f "$STUBDIR/.created"
+  run env STUB_KEY_STATUS=200 ACQ_BACKEND=sbx "$ACQ" create opencode "$proj"
+  assert_failure
+  assert_output --partial "unknown kit 'git+https://evil.example/x.git#ref=abc&dir=kit'"
+  refute_regex "$(cat "$CALLS")" 'sbx create'
+  assert [ ! -f "$STUBDIR/.created" ]
+}
+
+@test "create(sbx): configured extra_kits reach sbx create kit flags" {
+  local proj="$STUBDIR/config-kit"; mkdir -p "$proj"
+  export XDG_CONFIG_HOME="$STUBDIR/xdg-config-kit"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'extra_kits: openchamber\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  mkdir -p "$STUBDIR/secrets"; printf 'sk-stored-and-bound\n' > "$STUBDIR/secrets/acq.usai"
+  seed_sbx_usai_proxy_fixture
+  run env STUB_KEY_STATUS=200 ACQ_BACKEND=sbx "$ACQ" create opencode "$proj"
+  assert_success
+  local create_line; create_line=$(grep '^sbx create' "$CALLS")
+  assert_regex "$create_line" '--kit git\+https://github.com/GSA-TTS/agentic-coding-patterns.git#ref=.*&dir=integrations/isolation/acq-kits/openchamber'
+}
+
+@test "run(sbx): configured extra_kits reach fresh sbx create kit flags" {
+  local proj="$STUBDIR/run-config-kit"; mkdir -p "$proj"
+  export XDG_CONFIG_HOME="$STUBDIR/xdg-run-config-kit"
+  mkdir -p "$XDG_CONFIG_HOME/acq"
+  printf 'extra_kits: openchamber\n' > "$XDG_CONFIG_HOME/acq/config.yaml"
+  mkdir -p "$STUBDIR/secrets"; printf 'sk-stored-and-bound\n' > "$STUBDIR/secrets/acq.usai"
+  seed_sbx_usai_proxy_fixture
+  run env STUB_KEY_STATUS=200 ACQ_BACKEND=sbx STUB_OPENCODE_OK=1 "$ACQ" run opencode "$proj"
+  assert_success
+  local create_line; create_line=$(grep '^sbx create' "$CALLS")
+  assert_regex "$create_line" '--kit git\+https://github.com/GSA-TTS/agentic-coding-patterns.git#ref=.*&dir=integrations/isolation/acq-kits/openchamber'
+}
+
 @test "create(msb): host-exported USAI_API_KEY counts as present; provision proceeds" {
   local proj="$STUBDIR/kc-ci"; mkdir -p "$proj"
   rm -f "$STUBDIR/.msb_created"