diff --git a/bin/context-kit b/bin/context-kit
index 185c92e..34568f3 100755
--- a/bin/context-kit
+++ b/bin/context-kit
@@ -64,6 +64,13 @@ SHARED_SERVICES=(searxng "${WEB_SEARCH_SERVICE_NAME}" "${DOCS_SERVICE_NAME}")
 SNAPSHOT_IDS=()
 SNAPSHOT_RUNNING=()
 DOCS_SOURCES_FILE="${DATA_DIR}/docs-sources.txt"
+DOCS_SOURCES_TRANSACTION_ACTIVE=0
+DOCS_SOURCES_PRIOR_PRESENT=0
+DOCS_SOURCES_BACKUP_DIR=''
+DOCS_SOURCES_BACKUP_FILE=''
+DOCS_SOURCES_RENDER_TMP=''
+LIFECYCLE_STATE_ROLLBACK_ACTIVE=0
+LIFECYCLE_STATE_ROLLBACK_REMOVE_NEW=false
 DOCS_DATA_DIR="${DATA_DIR}/docs"
 MODELS_DATA_DIR="${DATA_DIR}/models"
 DOCS_LOCAL_SOURCES_DIR="${CONTEXT_KIT_DOCS_LOCAL_SOURCES_DIR:-${DATA_DIR}/local-sources}"
@@ -130,12 +137,104 @@ require_no_args() {
 
 write_docs_sources_file() {
   mkdir -p "$(dirname "${DOCS_SOURCES_FILE}")"
-  local tmp="${DOCS_SOURCES_FILE}.tmp.$$"
-  {
+  local tmp="${DOCS_SOURCES_FILE}.tmp.${BASHPID}"
+  DOCS_SOURCES_RENDER_TMP="${tmp}"
+  if ! {
     printf '# generated by context-kit lifecycle commands; edit your CONTEXT_KIT_DOCS_SOURCES file(s) instead\n'
     resolved_sources
-  } > "${tmp}"
-  mv "${tmp}" "${DOCS_SOURCES_FILE}"
+  } > "${tmp}"; then
+    rm -f -- "${tmp}"
+    DOCS_SOURCES_RENDER_TMP=''
+    return 1
+  fi
+  if ! mv -fT -- "${tmp}" "${DOCS_SOURCES_FILE}"; then
+    rm -f -- "${tmp}"
+    DOCS_SOURCES_RENDER_TMP=''
+    return 1
+  fi
+  DOCS_SOURCES_RENDER_TMP=''
+}
+
+reset_docs_sources_transaction() {
+  DOCS_SOURCES_TRANSACTION_ACTIVE=0
+  DOCS_SOURCES_PRIOR_PRESENT=0
+  DOCS_SOURCES_BACKUP_DIR=''
+  DOCS_SOURCES_BACKUP_FILE=''
+  DOCS_SOURCES_RENDER_TMP=''
+}
+
+begin_docs_sources_transaction() {
+  [[ "${DOCS_SOURCES_TRANSACTION_ACTIVE}" -eq 0 ]] || return 1
+  mkdir -p "$(dirname "${DOCS_SOURCES_FILE}")"
+
+  local backup_dir
+  backup_dir="$(mktemp -d "${DOCS_SOURCES_FILE}.lifecycle-backup.XXXXXX")" || return 1
+  DOCS_SOURCES_BACKUP_DIR="${backup_dir}"
+  DOCS_SOURCES_BACKUP_FILE="${backup_dir}/docs-sources.txt"
+  DOCS_SOURCES_PRIOR_PRESENT=0
+  DOCS_SOURCES_TRANSACTION_ACTIVE=1
+
+  if [[ -e "${DOCS_SOURCES_FILE}" || -L "${DOCS_SOURCES_FILE}" ]]; then
+    DOCS_SOURCES_PRIOR_PRESENT=1
+    if ! mv -T -- "${DOCS_SOURCES_FILE}" "${DOCS_SOURCES_BACKUP_FILE}"; then
+      rmdir -- "${DOCS_SOURCES_BACKUP_DIR}" 2>/dev/null || true
+      reset_docs_sources_transaction
+      return 1
+    fi
+  fi
+}
+
+restore_docs_sources_transaction() {
+  [[ "${DOCS_SOURCES_TRANSACTION_ACTIVE}" -eq 1 ]] || return 0
+  local failed=0
+
+  if [[ -n "${DOCS_SOURCES_RENDER_TMP}" ]]; then
+    rm -f -- "${DOCS_SOURCES_RENDER_TMP}" || failed=1
+    DOCS_SOURCES_RENDER_TMP=''
+  fi
+  if [[ "${DOCS_SOURCES_PRIOR_PRESENT}" -eq 1 ]]; then
+    if [[ -e "${DOCS_SOURCES_BACKUP_FILE}" || -L "${DOCS_SOURCES_BACKUP_FILE}" ]]; then
+      if ! mv -fT -- "${DOCS_SOURCES_BACKUP_FILE}" "${DOCS_SOURCES_FILE}"; then
+        warn "failed to restore prior docs sources file: ${DOCS_SOURCES_FILE}"
+        failed=1
+      fi
+    else
+      warn "prior docs sources backup is missing: ${DOCS_SOURCES_BACKUP_FILE}"
+      failed=1
+    fi
+  elif ! rm -f -- "${DOCS_SOURCES_FILE}"; then
+    warn "failed to restore prior absence of docs sources file: ${DOCS_SOURCES_FILE}"
+    failed=1
+  fi
+
+  if [[ "${failed}" -eq 0 ]] && ! rmdir -- "${DOCS_SOURCES_BACKUP_DIR}"; then
+    warn "failed to remove docs sources backup directory: ${DOCS_SOURCES_BACKUP_DIR}"
+    failed=1
+  fi
+  if [[ "${failed}" -eq 0 ]]; then
+    reset_docs_sources_transaction
+  fi
+  return "${failed}"
+}
+
+discard_docs_sources_transaction() {
+  [[ "${DOCS_SOURCES_TRANSACTION_ACTIVE}" -eq 1 ]] || return 0
+  local failed=0
+
+  if [[ -n "${DOCS_SOURCES_RENDER_TMP}" ]]; then
+    rm -f -- "${DOCS_SOURCES_RENDER_TMP}" || failed=1
+    DOCS_SOURCES_RENDER_TMP=''
+  fi
+  if [[ "${DOCS_SOURCES_PRIOR_PRESENT}" -eq 1 ]]; then
+    rm -f -- "${DOCS_SOURCES_BACKUP_FILE}" || failed=1
+  fi
+  if [[ "${failed}" -eq 0 ]] && ! rmdir -- "${DOCS_SOURCES_BACKUP_DIR}"; then
+    failed=1
+  fi
+  if [[ "${failed}" -eq 0 ]]; then
+    reset_docs_sources_transaction
+  fi
+  return "${failed}"
 }
 
 ensure_writable_dir() {
@@ -491,6 +590,34 @@ restore_shared_service_states() {
   return "${failed}"
 }
 
+rollback_lifecycle_transaction() {
+  local failed=0
+  restore_docs_sources_transaction || failed=1
+  if [[ "${LIFECYCLE_STATE_ROLLBACK_ACTIVE}" -eq 1 ]]; then
+    restore_shared_service_states "${LIFECYCLE_STATE_ROLLBACK_REMOVE_NEW}" || failed=1
+    LIFECYCLE_STATE_ROLLBACK_ACTIVE=0
+  fi
+  return "${failed}"
+}
+
+lifecycle_transaction_exit() {
+  local status="$1"
+  trap - EXIT HUP INT TERM
+  rollback_lifecycle_transaction || true
+  exit "${status}"
+}
+
+arm_lifecycle_transaction_traps() {
+  trap 'lifecycle_transaction_exit "$?"' EXIT
+  trap 'exit 129' HUP
+  trap 'exit 130' INT
+  trap 'exit 143' TERM
+}
+
+disarm_lifecycle_transaction_traps() {
+  trap - EXIT HUP INT TERM
+}
+
 shared_services_ready() {
   wait_for_searxng && wait_for_web_search_mcp && wait_for_docs_mcp
 }
@@ -500,18 +627,42 @@ start_locked() {
   if ! docker image inspect "${WEB_SEARCH_IMAGE}" >/dev/null 2>&1 || ! docker image inspect "${DOCS_IMAGE}" >/dev/null 2>&1; then
     cmd_build
   fi
-  write_docs_sources_file
-
-  local result=0
+  local result=0 rollback_failed=0
+  arm_lifecycle_transaction_traps
+  if begin_docs_sources_transaction; then
+    :
+  else
+    result=$?
+    disarm_lifecycle_transaction_traps
+    return "${result}"
+  fi
+  if write_docs_sources_file; then
+    :
+  else
+    result=$?
+    rollback_lifecycle_transaction || rollback_failed=1
+    disarm_lifecycle_transaction_traps
+    [[ "${rollback_failed}" -eq 0 ]] || return 1
+    return "${result}"
+  fi
   snapshot_shared_services
+  LIFECYCLE_STATE_ROLLBACK_ACTIVE=1
+  LIFECYCLE_STATE_ROLLBACK_REMOVE_NEW=true
   compose up -d --no-recreate "${SHARED_SERVICES[@]}" || result=$?
   if [[ "${result}" -eq 0 ]] && ! shared_services_ready; then
     result=1
   fi
-  [[ "${result}" -ne 0 ]] || return 0
+  if [[ "${result}" -eq 0 ]] && discard_docs_sources_transaction; then
+    LIFECYCLE_STATE_ROLLBACK_ACTIVE=0
+    disarm_lifecycle_transaction_traps
+    return 0
+  fi
+  [[ "${result}" -ne 0 ]] || result=1
 
-  warn "shared service startup failed; restoring prior container states"
-  restore_shared_service_states true || true
+  warn "shared service startup failed; restoring prior docs sources and container states"
+  rollback_lifecycle_transaction || rollback_failed=1
+  disarm_lifecycle_transaction_traps
+  [[ "${rollback_failed}" -eq 0 ]] || return 1
   return "${result}"
 }
 
@@ -538,17 +689,42 @@ cmd_restart() {
 }
 
 restart_locked() {
-  local result=0
-  write_docs_sources_file
+  local result=0 rollback_failed=0
+  arm_lifecycle_transaction_traps
+  if begin_docs_sources_transaction; then
+    :
+  else
+    result=$?
+    disarm_lifecycle_transaction_traps
+    return "${result}"
+  fi
+  if write_docs_sources_file; then
+    :
+  else
+    result=$?
+    rollback_lifecycle_transaction || rollback_failed=1
+    disarm_lifecycle_transaction_traps
+    [[ "${rollback_failed}" -eq 0 ]] || return 1
+    return "${result}"
+  fi
   snapshot_shared_services
+  LIFECYCLE_STATE_ROLLBACK_ACTIVE=1
+  LIFECYCLE_STATE_ROLLBACK_REMOVE_NEW=false
   compose restart "${SHARED_SERVICES[@]}" || result=$?
   if [[ "${result}" -eq 0 ]] && ! shared_services_ready; then
     result=1
   fi
-  [[ "${result}" -ne 0 ]] || return 0
+  if [[ "${result}" -eq 0 ]] && discard_docs_sources_transaction; then
+    LIFECYCLE_STATE_ROLLBACK_ACTIVE=0
+    disarm_lifecycle_transaction_traps
+    return 0
+  fi
+  [[ "${result}" -ne 0 ]] || result=1
 
-  warn "shared service restart failed; restoring prior container states"
-  restore_shared_service_states false || true
+  warn "shared service restart failed; restoring prior docs sources and container states"
+  rollback_lifecycle_transaction || rollback_failed=1
+  disarm_lifecycle_transaction_traps
+  [[ "${rollback_failed}" -eq 0 ]] || return 1
   return "${result}"
 }
 
diff --git a/docker/docs/Dockerfile b/docker/docs/Dockerfile
index 74d59a4..e624990 100644
--- a/docker/docs/Dockerfile
+++ b/docker/docs/Dockerfile
@@ -29,7 +29,7 @@ RUN if [ -n "${LLMS_TXT_MCP_VERSION}" ]; then \
  && rm /tmp/context-kit-docs-constraints.txt
 
 COPY entrypoint.sh /usr/local/bin/docs-mcp-entrypoint
-RUN chmod +x /usr/local/bin/docs-mcp-entrypoint
+RUN chmod 0555 /usr/local/bin/docs-mcp-entrypoint
 
 RUN mkdir -p /data /models /etc/context-kit
 ENV HF_HOME=/models \
diff --git a/docker/web-search/.dockerignore b/docker/web-search/.dockerignore
index 77333f4..b912d3c 100644
--- a/docker/web-search/.dockerignore
+++ b/docker/web-search/.dockerignore
@@ -1,5 +1,7 @@
 *
 !Dockerfile
+!http-entrypoint.mjs
+!mcp-probe.mjs
 !patch-mcp-web-search.mjs
 !overrides/
 !overrides/bing.js
diff --git a/docker/web-search/Dockerfile b/docker/web-search/Dockerfile
index 8c86371..86b7922 100644
--- a/docker/web-search/Dockerfile
+++ b/docker/web-search/Dockerfile
@@ -29,6 +29,8 @@ RUN npm install -g "@zhafron/mcp-web-search@${MCP_WEB_SEARCH_VERSION}" \
   && rm /tmp/patch-mcp-web-search.mjs /tmp/context-kit-bing-provider.js \
   && npm cache clean --force
 
+RUN chmod 0555 /usr/local/lib/context-kit
+
 ENV CHROME_PATH=/usr/bin/chromium \
   DEFAULT_SEARCH_PROVIDER=searxng \
   HOME=/tmp \
diff --git a/scripts/release-check b/scripts/release-check
index dc1b6be..d9ee9ef 100755
--- a/scripts/release-check
+++ b/scripts/release-check
@@ -1,6 +1,83 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
+cleanup_ephemeral_lifecycle_lock() {
+  local project="${1:-}" lock_dir lock_file owner mode lock_owner
+  [[ "${project}" =~ ^context-kit-release-[0-9]+$ ]] || {
+    printf 'release-check: refusing non-release lifecycle lock project: %s\n' "${project}" >&2
+    return 64
+  }
+  command -v flock >/dev/null 2>&1 || {
+    printf 'release-check: flock is required for lifecycle lock cleanup\n' >&2
+    return 1
+  }
+  command -v stat >/dev/null 2>&1 || {
+    printf 'release-check: stat is required for lifecycle lock cleanup\n' >&2
+    return 1
+  }
+
+  lock_dir="/tmp/context-kit-${project}.lock"
+  lock_file="${lock_dir}/lifecycle"
+  [[ -e "${lock_dir}" || -L "${lock_dir}" ]] || return 0
+  [[ -d "${lock_dir}" && ! -L "${lock_dir}" ]] || {
+    printf 'release-check: refusing unsafe lifecycle lock path: %s\n' "${lock_dir}" >&2
+    return 1
+  }
+  if [[ -e "${lock_file}" || -L "${lock_file}" ]]; then
+    [[ -f "${lock_file}" && ! -L "${lock_file}" ]] || {
+      printf 'release-check: refusing unsafe lifecycle lock file: %s\n' "${lock_file}" >&2
+      return 1
+    }
+  fi
+
+  (
+    exec 9>"${lock_file}" || return 1
+    if ! flock -n 9; then
+      printf 'release-check: lifecycle lock is still held: %s\n' "${lock_dir}" >&2
+      return 1
+    fi
+
+    [[ -d "${lock_dir}" && ! -L "${lock_dir}" ]] || {
+      printf 'release-check: lifecycle lock path changed while acquiring it: %s\n' "${lock_dir}" >&2
+      return 1
+    }
+    owner="$(stat -c %u "${lock_dir}")"
+    mode="$(stat -c %a "${lock_dir}")"
+    [[ "${owner}" == "$(id -u)" && "${mode}" == "700" ]] || {
+      printf 'release-check: refusing lifecycle lock with uid %s and mode %s: %s\n' "${owner}" "${mode}" "${lock_dir}" >&2
+      return 1
+    }
+    [[ -f "${lock_file}" && ! -L "${lock_file}" ]] || {
+      printf 'release-check: lifecycle lock file changed while acquiring it: %s\n' "${lock_file}" >&2
+      return 1
+    }
+    lock_owner="$(stat -c %u "${lock_file}")"
+    [[ "${lock_owner}" == "$(id -u)" ]] || {
+      printf 'release-check: refusing lifecycle lock file owned by uid %s: %s\n' "${lock_owner}" "${lock_file}" >&2
+      return 1
+    }
+
+    rm -f -- "${lock_file}"
+    if ! rmdir -- "${lock_dir}"; then
+      printf 'release-check: lifecycle lock directory contains unexpected entries: %s\n' "${lock_dir}" >&2
+      return 1
+    fi
+  )
+}
+
+if [[ "${1:-}" == "--cleanup-ephemeral-lock" ]]; then
+  [[ "$#" -eq 2 ]] || {
+    printf 'usage: scripts/release-check --cleanup-ephemeral-lock context-kit-release-PID\n' >&2
+    exit 64
+  }
+  cleanup_ephemeral_lifecycle_lock "$2"
+  exit
+fi
+[[ "$#" -eq 0 ]] || {
+  printf 'usage: scripts/release-check\n' >&2
+  exit 64
+}
+
 ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
 cd "${ROOT}"
 
@@ -44,9 +121,16 @@ printf '%s\n' \
 printf '%s\n' "${CONTEXT_KIT_LOCAL_SOURCE_SMOKE_URL}" > "${local_sources_profile}"
 
 cleanup() {
+  local status="$?" lock_status=0
+  trap - EXIT
   docker compose -p "${CONTEXT_KIT_COMPOSE_PROJECT}" -f compose.yml down -v --remove-orphans >/dev/null 2>&1 || true
   docker image rm "${CONTEXT_KIT_WEB_SEARCH_IMAGE}" "${CONTEXT_KIT_DOCS_IMAGE}" >/dev/null 2>&1 || true
+  cleanup_ephemeral_lifecycle_lock "${CONTEXT_KIT_COMPOSE_PROJECT}" || lock_status=$?
   rm -rf "${tmp_dir}"
+  if [[ "${status}" -ne 0 ]]; then
+    exit "${status}"
+  fi
+  exit "${lock_status}"
 }
 trap cleanup EXIT
 
diff --git a/scripts/test-lifecycle.sh b/scripts/test-lifecycle.sh
index 69a75ce..3f12d34 100644
--- a/scripts/test-lifecycle.sh
+++ b/scripts/test-lifecycle.sh
@@ -3,14 +3,27 @@ set -euo pipefail
 
 ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
 CONTEXT_KIT="${ROOT}/bin/context-kit"
+RELEASE_CHECK="${ROOT}/scripts/release-check"
 TEST_ROOT="$(mktemp -d)"
 TEST_PROJECT="context-kit-lifecycle-$$"
 LOCK_DIR="/tmp/context-kit-${TEST_PROJECT}.lock"
+RELEASE_LOCK_TEST_PROJECT="context-kit-release-$((900000000 + $$))"
+RELEASE_LOCK_DIR="/tmp/context-kit-${RELEASE_LOCK_TEST_PROJECT}.lock"
+LOCK_HOLDER_PID=''
 cleanup() {
+  if [[ -n "${LOCK_HOLDER_PID}" ]]; then
+    kill "${LOCK_HOLDER_PID}" 2>/dev/null || true
+    wait "${LOCK_HOLDER_PID}" 2>/dev/null || true
+  fi
   rm -rf "${TEST_ROOT}"
   if [[ -d "${LOCK_DIR}" && "$(stat -c %u "${LOCK_DIR}")" == "$(id -u)" ]]; then
     rm -rf "${LOCK_DIR}"
   fi
+  if [[ -L "${RELEASE_LOCK_DIR}" ]]; then
+    rm -f "${RELEASE_LOCK_DIR}"
+  elif [[ -d "${RELEASE_LOCK_DIR}" && "$(stat -c %u "${RELEASE_LOCK_DIR}")" == "$(id -u)" ]]; then
+    rm -rf "${RELEASE_LOCK_DIR}"
+  fi
 }
 trap cleanup EXIT
 
@@ -36,6 +49,16 @@ fake_service_for_container() {
   return 1
 }
 
+assert_docs_sources_restored_before_state_change() {
+  if [[ -n "${FAKE_EXPECT_DOCS_SOURCES:-}" ]]; then
+    cmp -s "${FAKE_EXPECT_DOCS_SOURCES}" "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" \
+      || fail_test "container state restoration ran before prior docs sources content was restored"
+  elif [[ "${FAKE_EXPECT_DOCS_SOURCES_ABSENT:-0}" -eq 1 ]]; then
+    [[ ! -e "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" && ! -L "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" ]] \
+      || fail_test "container state restoration ran before prior docs sources absence was restored"
+  fi
+}
+
 fake_compose() {
   while [[ "$#" -gt 0 ]]; do
     case "$1" in
@@ -164,12 +187,14 @@ docker() {
     start)
       local container_id="${!#}" service
       if service="$(fake_service_for_container "${container_id}" 2>/dev/null)"; then
+        assert_docs_sources_restored_before_state_change
         touch "${FAKE_DOCKER_STATE}/service.${service}.running"
       fi
       ;;
     rm)
       local container_id="${!#}" service
       if service="$(fake_service_for_container "${container_id}" 2>/dev/null)"; then
+        assert_docs_sources_restored_before_state_change
         rm -f "${FAKE_DOCKER_STATE}/service.${service}.id" "${FAKE_DOCKER_STATE}/service.${service}.running"
       fi
       rm -f "${FAKE_DOCKER_STATE}/owner.${container_id}"
@@ -177,6 +202,7 @@ docker() {
     stop)
       local container_id="${!#}" service
       service="$(fake_service_for_container "${container_id}")" || return 1
+      assert_docs_sources_restored_before_state_change
       rm -f "${FAKE_DOCKER_STATE}/service.${service}.running"
       ;;
     ps)
@@ -214,7 +240,7 @@ curl() {
 }
 
 sleep() { return 0; }
-export -f fail_test fake_log fake_service_for_container fake_compose docker curl sleep
+export -f fail_test fake_log fake_service_for_container assert_docs_sources_restored_before_state_change fake_compose docker curl sleep
 
 new_case() {
   local name="$1"
@@ -232,7 +258,8 @@ new_case() {
   export CONTEXT_KIT_DOCS_SOURCES=config/sources.default.txt
   unset CONTEXT_KIT_DOCKER_CIDFILE CONTEXT_KIT_RUNTIME_DIR FAKE_DOCS_UID FAKE_WEB_UID \
     FAKE_REPLACEMENT_REQUIRED FAKE_RESTART_FAIL FAKE_DROP_RUNNING FAKE_SEARXNG_FAIL \
-    FAKE_WEB_SEARCH_FAIL FAKE_DOCS_FAIL FAKE_LEGACY_CONTAINER FAKE_CLIENT_OWNER_MISMATCH
+    FAKE_WEB_SEARCH_FAIL FAKE_DOCS_FAIL FAKE_LEGACY_CONTAINER FAKE_CLIENT_OWNER_MISMATCH \
+    FAKE_EXPECT_DOCS_SOURCES FAKE_EXPECT_DOCS_SOURCES_ABSENT
   mkdir -p "${FAKE_DOCKER_STATE}" "${HOME}"
   : > "${FAKE_DOCKER_LOG}"
 }
@@ -245,6 +272,62 @@ seed_service() {
   fi
 }
 
+assert_no_docs_sources_artifacts() {
+  if compgen -G "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt.lifecycle-backup.*" >/dev/null \
+    || compgen -G "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt.tmp.*" >/dev/null; then
+    fail_test "docs sources transaction left backup or render artifacts"
+  fi
+}
+
+mkdir -m 700 "${RELEASE_LOCK_DIR}"
+: > "${RELEASE_LOCK_DIR}/lifecycle"
+chmod 755 "${RELEASE_LOCK_DIR}"
+if "${RELEASE_CHECK}" --cleanup-ephemeral-lock "${RELEASE_LOCK_TEST_PROJECT}" >"${TEST_ROOT}/unsafe-lock.out" 2>&1; then
+  fail_test "release lock cleanup accepted an unsafe mode"
+fi
+[[ -d "${RELEASE_LOCK_DIR}" ]] || fail_test "release lock cleanup removed an unsafe lock"
+chmod 700 "${RELEASE_LOCK_DIR}"
+"${RELEASE_CHECK}" --cleanup-ephemeral-lock "${RELEASE_LOCK_TEST_PROJECT}"
+
+release_lock_target="${TEST_ROOT}/release-lock-symlink-target"
+mkdir -m 700 "${release_lock_target}"
+touch "${release_lock_target}/sentinel"
+ln -s "${release_lock_target}" "${RELEASE_LOCK_DIR}"
+if "${RELEASE_CHECK}" --cleanup-ephemeral-lock "${RELEASE_LOCK_TEST_PROJECT}" >"${TEST_ROOT}/symlink-lock.out" 2>&1; then
+  fail_test "release lock cleanup followed a symlink"
+fi
+[[ -f "${release_lock_target}/sentinel" ]] || fail_test "release lock cleanup changed a symlink target"
+rm -f "${RELEASE_LOCK_DIR}"
+rm -rf "${release_lock_target}"
+
+mkdir -m 700 "${RELEASE_LOCK_DIR}"
+: > "${RELEASE_LOCK_DIR}/lifecycle"
+(
+  flock -x 9
+  touch "${TEST_ROOT}/release-lock-held"
+  /bin/sleep 30
+) 9>"${RELEASE_LOCK_DIR}/lifecycle" &
+LOCK_HOLDER_PID=$!
+for _ in {1..100}; do
+  [[ -f "${TEST_ROOT}/release-lock-held" ]] && break
+  /bin/sleep 0.01
+done
+[[ -f "${TEST_ROOT}/release-lock-held" ]] || fail_test "release lock holder did not start"
+if "${RELEASE_CHECK}" --cleanup-ephemeral-lock "${RELEASE_LOCK_TEST_PROJECT}" >"${TEST_ROOT}/held-lock.out" 2>&1; then
+  fail_test "release lock cleanup removed a held lock"
+fi
+grep -F 'still held' "${TEST_ROOT}/held-lock.out" >/dev/null || fail_test "held lock refusal was not explicit"
+kill "${LOCK_HOLDER_PID}"
+wait "${LOCK_HOLDER_PID}" 2>/dev/null || true
+LOCK_HOLDER_PID=''
+"${RELEASE_CHECK}" --cleanup-ephemeral-lock "${RELEASE_LOCK_TEST_PROJECT}"
+[[ ! -e "${RELEASE_LOCK_DIR}" && ! -L "${RELEASE_LOCK_DIR}" ]] || fail_test "successful release lock cleanup left the lock path"
+
+mkdir -m 700 "${RELEASE_LOCK_DIR}"
+: > "${RELEASE_LOCK_DIR}/lifecycle"
+"${RELEASE_CHECK}" --cleanup-ephemeral-lock "${RELEASE_LOCK_TEST_PROJECT}"
+[[ ! -e "${RELEASE_LOCK_DIR}" && ! -L "${RELEASE_LOCK_DIR}" ]] || fail_test "release lock cleanup did not remove its known ephemeral lock"
+
 new_case snippets
 "${CONTEXT_KIT}" install opencode > "${CASE_ROOT}/opencode.json"
 "${CONTEXT_KIT}" install claude > "${CASE_ROOT}/claude.json"
@@ -319,6 +402,12 @@ new_case readiness-failure
 touch "${FAKE_DOCKER_STATE}/network" "${FAKE_DOCKER_STATE}/volume"
 seed_service searxng
 seed_service docs-mcp stopped
+mkdir -p "${CONTEXT_KIT_DATA_DIR}"
+printf 'prior docs sources\nwith exact content\n' > "${CASE_ROOT}/prior-docs-sources.txt"
+cp "${CASE_ROOT}/prior-docs-sources.txt" "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt"
+printf 'https://new.example.test/llms.txt\n' > "${CASE_ROOT}/new-sources.txt"
+export CONTEXT_KIT_DOCS_SOURCES="${CASE_ROOT}/new-sources.txt"
+export FAKE_EXPECT_DOCS_SOURCES="${CASE_ROOT}/prior-docs-sources.txt"
 export FAKE_DROP_RUNNING=searxng
 export FAKE_WEB_SEARCH_FAIL=1
 if "${CONTEXT_KIT}" start >"${CASE_ROOT}/start.out" 2>&1; then
@@ -326,6 +415,9 @@ if "${CONTEXT_KIT}" start >"${CASE_ROOT}/start.out" 2>&1; then
 fi
 [[ -f "${FAKE_DOCKER_STATE}/service.searxng.running" ]] || fail_test "readiness rollback did not restart prior searxng"
 [[ ! -f "${FAKE_DOCKER_STATE}/service.docs-mcp.running" ]] || fail_test "readiness rollback did not restore prior stopped docs state"
+[[ "$(<"${FAKE_DOCKER_STATE}/service.docs-mcp.id")" == cid-docs-mcp ]] || fail_test "readiness rollback changed the prior docs container ID"
+cmp -s "${CASE_ROOT}/prior-docs-sources.txt" "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" || fail_test "readiness rollback did not restore prior docs sources content"
+assert_no_docs_sources_artifacts
 [[ ! -f "${FAKE_DOCKER_STATE}/service.web-search-mcp.id" ]] || fail_test "readiness rollback left its new web container"
 [[ -f "${FAKE_DOCKER_STATE}/network" && -f "${FAKE_DOCKER_STATE}/volume" ]] || fail_test "readiness rollback removed origin resources"
 
@@ -338,20 +430,41 @@ export CONTEXT_KIT_DOCS_SOURCES="${CASE_ROOT}/sources.txt"
 "${CONTEXT_KIT}" restart
 grep -F 'https://example.test/llms.txt' "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" >/dev/null \
   || fail_test "restart did not regenerate the bind-mounted docs source list"
+assert_no_docs_sources_artifacts
 
 new_case restart-failure
 seed_service searxng stopped
 seed_service web-search-mcp
-seed_service docs-mcp
-export FAKE_DROP_RUNNING=docs-mcp
-export FAKE_RESTART_FAIL=1
+seed_service docs-mcp stopped
+mkdir -p "${CONTEXT_KIT_DATA_DIR}"
+printf 'prior restart sources\n' > "${CASE_ROOT}/prior-docs-sources.txt"
+cp "${CASE_ROOT}/prior-docs-sources.txt" "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt"
+printf 'https://restart.example.test/llms.txt\n' > "${CASE_ROOT}/new-sources.txt"
+export CONTEXT_KIT_DOCS_SOURCES="${CASE_ROOT}/new-sources.txt"
+export FAKE_EXPECT_DOCS_SOURCES="${CASE_ROOT}/prior-docs-sources.txt"
+export FAKE_DOCS_FAIL=1
 if "${CONTEXT_KIT}" restart >"${CASE_ROOT}/restart.out" 2>&1; then
   fail_test "restart failure unexpectedly succeeded"
 fi
-[[ -f "${FAKE_DOCKER_STATE}/service.docs-mcp.running" ]] || fail_test "restart rollback left prior docs down"
+[[ ! -f "${FAKE_DOCKER_STATE}/service.docs-mcp.running" ]] || fail_test "restart rollback did not restore prior stopped docs state"
+[[ "$(<"${FAKE_DOCKER_STATE}/service.docs-mcp.id")" == cid-docs-mcp ]] || fail_test "restart rollback changed the prior docs container ID"
 [[ ! -f "${FAKE_DOCKER_STATE}/service.searxng.running" ]] || fail_test "restart rollback did not restore prior stopped SearXNG state"
+cmp -s "${CASE_ROOT}/prior-docs-sources.txt" "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" || fail_test "restart rollback did not restore prior docs sources content"
+assert_no_docs_sources_artifacts
 grep -F 'docker rm' "${FAKE_DOCKER_LOG}" >/dev/null && fail_test "restart rollback removed a shared container"
 
+new_case render-error
+mkdir -p "${CONTEXT_KIT_DATA_DIR}"
+printf 'prior render-error sources\n' > "${CASE_ROOT}/prior-docs-sources.txt"
+cp "${CASE_ROOT}/prior-docs-sources.txt" "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt"
+export CONTEXT_KIT_DOCS_SOURCES="${CASE_ROOT}/missing-sources.txt"
+if "${CONTEXT_KIT}" start >"${CASE_ROOT}/start.out" 2>&1; then
+  fail_test "docs sources render error unexpectedly succeeded"
+fi
+cmp -s "${CASE_ROOT}/prior-docs-sources.txt" "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" || fail_test "render error did not restore prior docs sources"
+assert_no_docs_sources_artifacts
+grep -F ' up ' "${FAKE_DOCKER_LOG}" >/dev/null && fail_test "render error reached Compose startup"
+
 new_case cross-user
 seed_service docs-mcp
 export FAKE_DOCS_UID="$(( $(id -u) + 1 ))"
@@ -363,12 +476,18 @@ grep -F ' up ' "${FAKE_DOCKER_LOG}" >/dev/null && fail_test "cross-user rejectio
 
 new_case bounded-failure
 export FAKE_WEB_SEARCH_FAIL=1
+export FAKE_EXPECT_DOCS_SOURCES_ABSENT=1
+[[ ! -e "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" && ! -L "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" ]] \
+  || fail_test "prior-absence case unexpectedly began with docs sources"
 if "${CONTEXT_KIT}" start >"${CASE_ROOT}/start.out" 2>&1; then
   fail_test "fresh readiness failure unexpectedly succeeded"
 fi
 for service in searxng web-search-mcp docs-mcp; do
   [[ ! -f "${FAKE_DOCKER_STATE}/service.${service}.id" ]] || fail_test "fresh failure left ${service}"
 done
+[[ ! -e "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" && ! -L "${CONTEXT_KIT_DATA_DIR}/docs-sources.txt" ]] \
+  || fail_test "fresh readiness rollback did not restore prior docs sources absence"
+assert_no_docs_sources_artifacts
 [[ -f "${FAKE_DOCKER_STATE}/network" && -f "${FAKE_DOCKER_STATE}/volume" ]] || fail_test "bounded shared resources were destructively removed"
 
 new_case legacy-status