diff --git a/docs/implementation-plan.v1.md b/docs/implementation-plan.v1.md
index 2ec8dbe..e5cc1c6 100644
--- a/docs/implementation-plan.v1.md
+++ b/docs/implementation-plan.v1.md
@@ -190,7 +190,7 @@ scripts/test-unit                 [--package PATTERN] [--run REGEXP] [--race]
 scripts/test-integration          [--suite NAME|all] [--run-id ID] [--resume]
 scripts/test-e2e                  [--scenario NAME|all] [--run-id ID] [--resume]
 scripts/test-env                  doctor|coverage|status|logs|collect|recover|reuse|stop|reset|purge|gc ...
-scripts/build                     build|verify (pinned toolchain; host-safe)
+scripts/build                     build|verify|doctor|recover|clean (pinned toolchain; host-safe)
 scripts/windows/build-test-bundle --run-id ID --config FILE [--ca FILE]
 scripts/windows/test-host         status|prepare|stage|run|collect|stop|reset|recover
 ```
@@ -208,6 +208,13 @@ exact `.test-runs/<run-id>` directory, with source-commit and SHA-256 manifest;
 it refuses replacement rather than overwriting an earlier bundle. This is not a
 release publisher: signing, version resources, and public checksum publication
 remain Phase 8 gates.
+It must report the exact RVBox toolchain image/cache/artifact footprint and
+provide a dry-run-first cleanup that can remove only the ignored `bin/` output,
+the exact toolchain image, and its two named Go-cache volumes. Cleanup requires
+`--execute` plus interactive confirmation (or CI `--yes`), refuses images used
+by containers, never touches `.test-runs/`, and never invokes a global Docker
+prune. `scripts/build recover` must rebuild the toolchain image and binaries
+after any or all of those owned resources were cleared.
 
 The first integration/E2E invocation creates a filesystem-safe random run ID,
 or validates an explicitly supplied one, and records
diff --git a/docs/testing.md b/docs/testing.md
index 35e3da4..2d31744 100644
--- a/docs/testing.md
+++ b/docs/testing.md
@@ -21,6 +21,22 @@ Build all supported binaries without installing `make` or Go on the host:
 scripts/build build
 ```
 
+`scripts/build doctor` reports the exact owned builder image, Go cache volumes,
+and ignored `bin/` artifact directory. To reclaim space, cleanup is dry-run by
+default and never performs a global Docker prune:
+
+```sh
+scripts/build clean --all
+scripts/build clean --all --execute --yes
+scripts/build recover
+```
+
+The second command removes only `bin/`, `rvbox-dev-toolchain:latest`, and the
+two named RVBox Go-cache volumes. `recover` rebuilds the pinned toolchain and
+all binaries from source. It intentionally does not remove `.test-runs/`, which
+may contain resumable environments; use the exact-run `scripts/test-env purge`
+workflow for those.
+
 For a native Windows run, create the immutable per-run test bundle with the
 pinned toolchain. Supply a test-specific config whose endpoint and CA path are
 valid for that run; the command refuses to replace an existing bundle.
diff --git a/scripts/build b/scripts/build
index c5dc024..117980f 100755
--- a/scripts/build
+++ b/scripts/build
@@ -3,20 +3,154 @@
 set -eu
 
 repo_root=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)
-target=${1:-build}
-shift || true
+compose_file=$repo_root/deploy/compose.yaml
+toolchain_image=rvbox-dev-toolchain:latest
+cache_volumes='rvbox-dev_rvbox-go-build rvbox-dev_rvbox-go-mod'
 
-case $target in
-    build|verify) ;;
-    *)
-        printf '%s\n' 'usage: scripts/build [build|verify]' >&2
-        exit 2
-        ;;
-esac
-[ "$#" -eq 0 ] || {
-    printf '%s\n' 'scripts/build does not accept additional arguments' >&2
-    exit 2
+usage() {
+    cat <<'EOF'
+usage: scripts/build build|verify|doctor|recover|clean [options]
+
+  build             build supported binaries in the pinned toolchain
+  verify            run the normal pinned verification gate
+  doctor            read-only toolchain/artifact/cache availability report
+  recover           rebuild a missing/broken toolchain image, then build
+  clean             print owned cleanup targets; no deletion without --execute
+
+clean options:
+  --artifacts       remove only this repository's ignored bin/ directory
+  --toolchain       remove only rvbox-dev-toolchain:latest
+  --caches          remove only the two named RVBox Go cache volumes
+  --all             select all three owned target classes
+  --execute          perform the selected deletion (otherwise dry run)
+  --yes              skip the interactive confirmation; requires --execute
+
+Run artifacts below .test-runs/ are deliberately not a build-clean target.
+Use scripts/test-env purge --run-id ID (or its explicit --all workflow) so a
+resumable test environment is never removed by a build cleanup operation.
+EOF
 }
 
-cd "$repo_root"
-exec docker compose -f deploy/compose.yaml run --rm toolchain make "$target"
+fail() { printf '%s\n' "build: $*" >&2; exit 2; }
+
+docker_ready() {
+    docker version >/dev/null 2>&1 || fail "Docker is unavailable; start or repair Docker, then retry"
+    docker compose -f "$compose_file" version >/dev/null 2>&1 || fail "Docker Compose is unavailable"
+}
+
+ensure_toolchain() {
+    docker_ready
+    if ! docker image inspect "$toolchain_image" >/dev/null 2>&1; then
+        printf '%s\n' "build: toolchain image is absent; rebuilding from $compose_file" >&2
+        docker compose -f "$compose_file" build toolchain
+    fi
+}
+
+run_make() {
+    target=$1
+    ensure_toolchain
+    cd "$repo_root"
+    exec docker compose -f "$compose_file" run --rm toolchain make "$target"
+}
+
+size_of() {
+    path=$1
+    if [ -e "$path" ]; then du -sh "$path" 2>/dev/null | awk '{print $1}' || printf '%s' '?'; else printf '%s' '0'; fi
+}
+
+doctor() {
+    docker_ready
+    printf 'repository=%s\n' "$repo_root"
+    if docker image inspect "$toolchain_image" >/dev/null 2>&1; then
+        printf 'toolchain_image=%s present\n' "$toolchain_image"
+    else
+        printf 'toolchain_image=%s absent (scripts/build build will rebuild it)\n' "$toolchain_image"
+    fi
+    for volume in $cache_volumes; do
+        if docker volume inspect "$volume" >/dev/null 2>&1; then
+            printf 'cache_volume=%s present\n' "$volume"
+        else
+            printf 'cache_volume=%s absent (Go will repopulate it)\n' "$volume"
+        fi
+    done
+    printf 'build_artifacts=%s size=%s\n' "$repo_root/bin" "$(size_of "$repo_root/bin")"
+    printf '%s\n' 'test artifacts are managed separately by scripts/test-env'
+}
+
+confirm() {
+    [ "$yes" = yes ] && return 0
+    [ -t 0 ] || fail "--execute without a terminal requires --yes"
+    printf '%s' 'Proceed with exactly the printed RVBox cleanup targets? [y/N] ' >&2
+    read -r answer
+    [ "$answer" = y ] || [ "$answer" = Y ] || fail "cleanup cancelled"
+}
+
+clean() {
+    artifacts=no
+    toolchain=no
+    caches=no
+    execute=no
+    yes=no
+    while [ "$#" -gt 0 ]; do
+        case $1 in
+            --artifacts) artifacts=yes ;;
+            --toolchain) toolchain=yes ;;
+            --caches) caches=yes ;;
+            --all) artifacts=yes; toolchain=yes; caches=yes ;;
+            --execute) execute=yes ;;
+            --yes) yes=yes ;;
+            --help|-h) usage; return 0 ;;
+            *) fail "unknown clean option $1" ;;
+        esac
+        shift
+    done
+    [ "$artifacts" = yes ] || [ "$toolchain" = yes ] || [ "$caches" = yes ] || fail "select at least one clean target"
+    docker_ready
+    printf '%s\n' 'RVBox cleanup targets:'
+    if [ "$artifacts" = yes ]; then
+        if [ -L "$repo_root/bin" ]; then fail "refusing symlink build-artifact target $repo_root/bin"; fi
+        printf '  artifact_dir=%s size=%s\n' "$repo_root/bin" "$(size_of "$repo_root/bin")"
+    fi
+    if [ "$toolchain" = yes ]; then
+        if docker image inspect "$toolchain_image" >/dev/null 2>&1; then
+            users=$(docker ps -a --filter "ancestor=$toolchain_image" --format '{{.ID}}' | wc -l | tr -d ' ')
+            printf '  toolchain_image=%s containers=%s\n' "$toolchain_image" "$users"
+            [ "$users" = 0 ] || fail "refusing to remove an image still referenced by containers"
+        else
+            printf '  toolchain_image=%s absent\n' "$toolchain_image"
+        fi
+    fi
+    if [ "$caches" = yes ]; then
+        for volume in $cache_volumes; do
+            if docker volume inspect "$volume" >/dev/null 2>&1; then
+                printf '  cache_volume=%s\n' "$volume"
+            else
+                printf '  cache_volume=%s absent\n' "$volume"
+            fi
+        done
+    fi
+    if [ "$execute" != yes ]; then
+        printf '%s\n' 'dry run only; rerun with --execute (and optionally --yes) to delete these exact targets'
+        return 0
+    fi
+    confirm
+    if [ "$artifacts" = yes ] && [ -d "$repo_root/bin" ]; then rm -rf "$repo_root/bin"; fi
+    if [ "$toolchain" = yes ] && docker image inspect "$toolchain_image" >/dev/null 2>&1; then docker image rm "$toolchain_image"; fi
+    if [ "$caches" = yes ]; then
+        for volume in $cache_volumes; do
+            if docker volume inspect "$volume" >/dev/null 2>&1; then docker volume rm "$volume"; fi
+        done
+    fi
+    printf '%s\n' 'RVBox build cleanup complete; scripts/build recover will recreate the toolchain and build artifacts.'
+}
+
+command=${1:-build}
+shift || true
+case $command in
+    build|verify) [ "$#" -eq 0 ] || fail "$command does not accept additional arguments"; run_make "$command" ;;
+    doctor) [ "$#" -eq 0 ] || fail "doctor does not accept additional arguments"; doctor ;;
+    recover) [ "$#" -eq 0 ] || fail "recover does not accept additional arguments"; docker_ready; docker compose -f "$compose_file" build toolchain; run_make build ;;
+    clean) clean "$@" ;;
+    --help|-h) usage ;;
+    *) usage >&2; fail "unknown command $command" ;;
+esac