diff --git a/scripts/check-phase19.4.sh b/scripts/check-phase19.4.sh
new file mode 100755
index 00000000..8d779ea8
--- /dev/null
+++ b/scripts/check-phase19.4.sh
@@ -0,0 +1,610 @@
+#!/usr/bin/env bash
+# check-phase19.4: fail-closed gate for Phase 19.4, the OpenID Connect
+# provider on wristband. It proves the phase across four repositories:
+# this framework (wristband's OIDC flavour and its MCP flavour unchanged,
+# tide's form capture, the docs), the shared OAuth server plugin, the shared
+# user plugin (its additive exports) and the application that runs the MCP
+# flavour (its OAuth suites, unchanged behaviour).
+#
+# Stages:
+#   go          go vet ./... and go test -short ./... here, then the
+#               Docker-free wristband and tide suites by required name.
+#   plugin      go vet ./... and go test -short ./... in the OAuth server
+#               plugin, then its Docker-free suites by required name.
+#   userplugin  go vet and go test -short of the user plugin (through the
+#               application workspace), its Docker-free suites by required
+#               name, and the additive check: since the user plugin's last
+#               commit before the phase, no line declaring an exported func,
+#               method or type was removed from a non-test .go file.
+#   fonoteka    the application's MCP flavour (D-09): go vet of the app and
+#               its domain plugin, go test -short of the domain plugin and
+#               its Docker-free OAuth suites by required name.
+#   docker      Docker host only: the testcontainers (Postgres) suites by
+#               required name in the OAuth server plugin, the user plugin and
+#               the application's OAuth suites. The application's unrelated
+#               admin route allowlist test is not part of this phase and is
+#               not run here (deferred-items.md).
+#   parity      the PHP parity replay (D-14): with recorded flows it runs
+#               TestPHPParityReplay and TestIDTokenShapeParity with
+#               PHASE194_REQUIRE_PARITY=1 (Docker host); without recordings
+#               it prints NOT RUN parity (D-14 unproven) and passes unless
+#               PHASE194_REQUIRE_PARITY=1. By the D-14 amendment of
+#               2026-10-19 the recording is deferred to the cutover of the
+#               PHP reference site, so NOT RUN does not hold the verdict.
+#   docs        the decision note's dependency names, TestDocsTree,
+#               summer docs:build --check, and no wristband source, OAuth
+#               server docs page or plugin file naming a consuming
+#               application.
+#
+# A stage exits non-zero on a failing command, or on a go test -json run that
+# fails, skips a test (a subtest included), matches zero tests, prints "no
+# tests to run" or misses a required name (a subtest pass never counts for
+# its parent's name). --self-test proves the detectors on planted output and
+# the docker and parity NOT RUN rules on a faked host.
+#
+# --all runs self-test, go, plugin, userplugin, fonoteka and docs, then
+# docker when a Docker daemon answers (NOT RUN docker otherwise, a failure
+# with PHASE194_REQUIRE_DOCKER=1), then parity (NOT RUN parity without
+# recordings, a failure with PHASE194_REQUIRE_PARITY=1).
+#
+# Environment overrides (default: the sibling checkouts next to this
+# repository): PHASE194_ROOT (this repository), OAUTHSERVER_PLUGIN,
+# USER_PLUGIN, FONOTEKA (the application workspace), PHASE194_USER_BASE
+# (the user plugin commit the additive check compares against).
+set -euo pipefail
+
+unset FORCE_COLOR
+export NO_COLOR=1
+
+ROOT="${PHASE194_ROOT:-$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)}"
+OAUTHSERVER_PLUGIN="${OAUTHSERVER_PLUGIN:-$ROOT/../sm-oauthserver-plugin}"
+FONOTEKA="${FONOTEKA:-$ROOT/../fono""teka.go}"
+USER_PLUGIN="${USER_PLUGIN:-$FONOTEKA/plugins/golem15/user}"
+# The user plugin's last commit before this phase (19-04).
+USER_BASE="${PHASE194_USER_BASE:-c077029}"
+
+# ---------------------------------------------------------------------------
+# Required test names. Each list runs with -run '^(a|b|...)$' and every name
+# must pass; a name that skips or does not run fails the stage.
+
+# go stage: wristband's OIDC flavour, its MCP regression and tide (-short).
+WRISTBAND_TESTS=(
+	# Plan 01 tracer and smokes.
+	TestOIDCTracerSmoke
+	TestOIDCAuthorizeStartSmoke TestOIDCResumeDecideSwitchSmoke TestKindIsolationSmoke
+	TestPHPRedirectEncodingSmoke
+	TestOIDCTokenErrorsSmoke TestOIDCReplayRevokesSmoke TestOIDCUserInfoSmoke
+	TestMixedKeyRingSmoke TestPairwiseSubjectSmoke TestOIDCRefreshOptInSmoke
+	TestDefaultOptionsResourceEmpty ExampleNewOIDCServer
+	# Plan 03 security review pins.
+	TestOIDCCodeBindingSmoke TestOIDCLogsCarryNoCredentials TestOIDCSubjectIsRandomSmoke
+	# MCP flavour unchanged (D-07): the phase 08 coverage suite.
+	TestPhase08Coverage
+)
+TIDE_TESTS=(TestCaptureResponseFormField)
+
+# plugin stage: the OAuth server plugin's Docker-free suites (-short).
+PLUGIN_TESTS=(
+	TestAdminSurfaceHidesCredentials
+	TestImportKeyDirErrorsNameNoKey
+	TestParityFixturesHoldNoSecrets
+)
+PLUGIN_CONSOLE_TESTS=()
+
+# userplugin stage: the user plugin's Docker-free suites (-short), by
+# package pattern relative to the application workspace.
+USER_CLASSES_TESTS=()
+USER_ROOT_TESTS=()
+
+# fonoteka stage: the application's Docker-free OAuth suites (-short).
+APP_OAUTH_TESTS=(
+	TestOAuthMetadataAssembled TestOAuthMetadataRouteIsolation TestOAuthMetadataIssuerTracksAppURL
+)
+
+# docker stage: testcontainers suites.
+DOCKER_PLUGIN_TESTS=(
+	# Plan 02.
+	TestOIDCFlowSmoke TestKeyRingFirstKeyRaceSmoke
+	TestConsentPageBrandingSmoke TestLoginHandoffAndSwitchSmoke TestBucketKeysSmoke TestRouteGuardSmoke
+	TestAuthorizationsSmoke TestUserCascadeSmoke TestMCPStoreSmoke
+	TestRelyingPartyInterop
+	# Plan 03.
+	TestImportWinterCutoverSmoke TestClientsAdminSmoke TestBrandingAdminSmoke
+	TestRotateAndPruneSmoke TestScheduleSmoke TestTokenLimitsSmoke
+)
+DOCKER_PLUGIN_CONSOLE_TESTS=()
+DOCKER_USER_CLASSES_TESTS=()
+DOCKER_USER_ROOT_TESTS=()
+# The application's OAuth suites on Postgres (D-09), the explicit resource
+# of plan 01 included.
+DOCKER_APP_OAUTH_TESTS=(
+	TestOAuthResourceExplicit
+	TestPhase8RedAuthorizeApp TestOAuthAuthorizeAssembled TestOAuthAuthorizeInvalidRequestsCreateNoPendingRows
+	TestOAuthAuthorizeRawRouteSurface
+	TestPhase8RedConsentApp TestOAuthConsentCrossUserIsNotFound TestOAuthConsentScopeCeilingViaShow
+	TestOAuthConsentEmptySubmittedScopeIntersectionIs422 TestOAuthDenyRedirectsAccessDeniedAndConsumesRequest
+	TestOAuthConsentMissingHandleIsNotFoundWithNoRequest TestOAuthConsentSurfaceIsolation
+	TestPhase8RedLifecycleApp TestConnectedAppsListEmptyThenPopulatedWithManualCount
+	TestConnectedAppsRevokeForeignAndMissingAndManualShareExact404
+	TestConnectedAppsRevokeKillsAccessAndRefreshThenDisappearsFromList TestOAuthConnectedAppsSurfaceIsolation
+	TestPhase8RedRegistrationApp TestOAuthRegisterAssembled TestOAuthRegisterOversizedAndWrongContentType
+	TestOAuthRawRegistrationSurface
+	TestPhase8RedMCPMe TestOAuthToolsMePositiveAndNegativeContract TestOAuthToolsMeRouteIsolation
+	TestOAuthMetadataAuthorizeWithoutClientIsLocalErrorAndRegisterExists
+	TestOAuthConsentIntersectionGrantsOnlyOriginallyRequestedScopes
+	TestOAuthConsentCollectionIDsAlwaysServerResolvedActivePin TestOAuthConsentSecondConsentOnSameRequestIDFails
+	TestOAuthConsentShowExactKeySet
+	TestOAuthRevocationRotatedPredecessorIsDeadAfterConnectedAppRevoke
+	TestOAuthRevocationRotatedTokenLeavesExactlyOneConnectedApp
+	TestOAuthRevocationManualTokenRouteKillsRefreshChain TestOAuthRevocationSecondGrantSurvivesRevokingFirst
+	TestOAuthRevocationListsSignalEachOtherExcludingOAuthFromManual
+	TestOAuthRevocationReadingOutsideAllowListRouteNotYetPorted
+	TestOAuthTokenSurfaceIsolationCoverage TestPhase08Coverage
+)
+
+# parity stage.
+PARITY_TESTS=(TestPHPParityReplay TestIDTokenShapeParity)
+# The todo that carries the deferred PHP recording (split so this file does
+# not name the site).
+PARITY_TODO=".planning/todos/pending/2026-10-19-record-php-oidc-parity-against-wave""path.md"
+
+# docs stage: names of consuming applications (split so this file does not
+# match itself), the decision note and the dependency names it must carry.
+APP_NAMES=("fono""teka" "p[lł]yta""rium" "grzy""by" "summercms""io" "wave""path" "stu""dia")
+DECISION_NOTE=".planning/notes/2026-10-19-oidc-on-wristband-golang-jwt.md"
+DECISION_NAMES=("golang-jwt/jwt/v5" "coreos/go-oidc/v3" "zitadel")
+
+usage() {
+	cat >&2 <<'EOF'
+usage:
+  check-phase19.4.sh --self-test
+  check-phase19.4.sh go | plugin | userplugin | fonoteka | docker | parity | docs
+  check-phase19.4.sh --go | --plugin | --userplugin | --fonoteka | --docker | --parity | --docs
+  check-phase19.4.sh --all
+EOF
+	exit 2
+}
+
+# detect_go reads go test -json. Exit 1 fail/build, 2 skip, 3 zero/no-tests,
+# 4 non-JSON, 5 missing required name.
+detect_go() {
+	python3 - "$1" <<'PY'
+import json, os, sys
+path = sys.argv[1]
+require = [n for n in os.environ.get("REQUIRE_TESTS", "").split() if n]
+passed = set()
+failed = []
+with open(path, encoding="utf-8", errors="replace") as fh:
+    for raw in fh:
+        line = raw.strip()
+        if not line.startswith("{"):
+            continue
+        try:
+            ev = json.loads(line)
+        except json.JSONDecodeError:
+            print("refuse: non-json test output", file=sys.stderr)
+            sys.exit(4)
+        action = ev.get("Action")
+        test = ev.get("Test") or ""
+        pkg = ev.get("Package") or ev.get("ImportPath") or ""
+        if action == "build-fail" or (action == "fail" and ev.get("FailedBuild")):
+            print(f"refuse: build failed {pkg}", file=sys.stderr)
+            sys.exit(1)
+        text = ev.get("Output") or ""
+        if action == "output" and "no tests to run" in text:
+            print(f"refuse: no tests to run in {pkg}", file=sys.stderr)
+            sys.exit(3)
+        if action == "skip" and test:
+            print(f"refuse: skipped {pkg} {test}", file=sys.stderr)
+            sys.exit(2)
+        if action == "fail":
+            failed.append(f"{pkg} {test}".strip())
+        if action == "pass" and test:
+            passed.add(test)
+if failed:
+    print("refuse: failed " + ", ".join(failed), file=sys.stderr)
+    sys.exit(1)
+if not passed:
+    print("refuse: zero tests", file=sys.stderr)
+    sys.exit(3)
+missing = [n for n in require if n not in passed]
+if missing:
+    print("refuse: required tests did not pass: " + ", ".join(missing), file=sys.stderr)
+    sys.exit(5)
+PY
+}
+
+# go_json DIR ARGS... runs go test -json ARGS in DIR (the workspace of a
+# sibling repository) and checks the stream with detect_go.
+go_json() {
+	local dir="$1"
+	shift
+	local log err rc=0 dc=0
+	log="$(mktemp)"
+	err="$(mktemp)"
+	(cd "$dir" && go test -json "$@") >"$log" 2>"$err" || rc=$?
+	detect_go "$log" || dc=$?
+	if [[ "$rc" -ne 0 || "$dc" -ne 0 ]]; then
+		cat "$err" >&2 || true
+		grep -v '^{' "$log" | tail -n 40 >&2 || true
+		python3 -c 'import json,sys
+for raw in open(sys.argv[1], errors="replace"):
+    try: ev = json.loads(raw)
+    except ValueError: continue
+    if ev.get("Action") == "output" and ("FAIL" in ev.get("Output", "") or "SKIP" in ev.get("Output", "") or "_test.go:" in ev.get("Output", "")):
+        sys.stderr.write(ev["Output"])' "$log" 2>&1 | tail -n 40 >&2 || true
+		rm -f "$log" "$err"
+		echo "refuse: go test $* in $dir (test=$rc detect=$dc)" >&2
+		return 1
+	fi
+	echo "go: $(grep -c '"Action":"pass","Package":"[^"]*","Test":"[^"/]*","Elapsed"' "$log") top-level tests passed in $dir ($*)"
+	rm -f "$log" "$err"
+}
+
+# go_named DIR PACKAGES FLAGS NAME... runs exactly the named top-level tests
+# and requires every one of them to pass. PACKAGES and FLAGS are word-split.
+go_named() {
+	local dir="$1" pkgs="$2" flags="$3"
+	shift 3
+	if [[ "$#" -eq 0 ]]; then
+		echo "refuse: go_named $pkgs in $dir without required names" >&2
+		return 1
+	fi
+	local names=("$@") regex
+	regex="^($(IFS='|'; echo "${names[*]}"))\$"
+	# shellcheck disable=SC2086
+	REQUIRE_TESTS="${names[*]}" go_json "$dir" $flags -count=1 -run "$regex" $pkgs
+}
+
+# go_short DIR PACKAGES runs go test -short PACKAGES in DIR; on failure it
+# prints the tail of the output and fails.
+go_short() {
+	local dir="$1" pkgs="${2:-./...}" out
+	# shellcheck disable=SC2086
+	if ! out="$(cd "$dir" && go test -count=1 -short $pkgs 2>&1)"; then
+		printf '%s\n' "$out" | grep -v '^ok ' | tail -n 60 >&2
+		echo "refuse: go test -short $pkgs in $dir" >&2
+		return 1
+	fi
+	echo "short: $dir ($pkgs)"
+}
+
+go_vet() {
+	local dir="$1"
+	shift
+	(cd "$dir" && go vet "$@")
+	echo "vet: $dir ($*)"
+}
+
+require_dir() {
+	[[ -d "$1" ]] || {
+		echo "refuse: $2 $1 not found" >&2
+		return 1
+	}
+}
+
+expect_detector() {
+	local detector="$1" name="$2" want="$3" payload="$4" log dc=0
+	log="$(mktemp)"
+	printf '%s\n' "$payload" >"$log"
+	"$detector" "$log" >/dev/null 2>&1 || dc=$?
+	rm -f "$log"
+	if [[ "$dc" -ne "$want" ]]; then
+		echo "refuse: self-test $detector $name: exit $dc, want $want" >&2
+		return 1
+	fi
+}
+
+# expect_mode NAME WANT_EXIT WANT_TEXT MODE ENV... runs this script in MODE
+# with ENV and checks its exit status and that its output carries WANT_TEXT.
+expect_mode() {
+	local name="$1" want="$2" text="$3" mode="$4"
+	shift 4
+	local out rc=0
+	out="$(env "$@" bash "${BASH_SOURCE[0]}" "$mode" 2>&1)" || rc=$?
+	if [[ "$rc" -ne "$want" ]] || ! grep -qF -- "$text" <<<"$out"; then
+		printf '%s\n' "$out" | tail -n 10 >&2
+		echo "refuse: self-test $name: exit $rc (want $want), output must carry \"$text\"" >&2
+		return 1
+	fi
+}
+
+run_self_test() {
+	bash -n "${BASH_SOURCE[0]}"
+
+	expect_detector detect_go pass 0 '{"Action":"pass","Package":"p","Test":"TestOIDCTracerSmoke"}'
+	expect_detector detect_go fail 1 '{"Action":"pass","Package":"p","Test":"TestA"}
+{"Action":"fail","Package":"p","Test":"TestPKCEAndReplay"}'
+	expect_detector detect_go package-fail 1 '{"Action":"pass","Package":"p","Test":"TestA"}
+{"Action":"fail","Package":"p"}'
+	expect_detector detect_go build 1 '{"Action":"build-fail","ImportPath":"p"}'
+	expect_detector detect_go skip 2 '{"Action":"pass","Package":"p","Test":"TestA"}
+{"Action":"skip","Package":"p","Test":"TestOIDCFlowSmoke"}'
+	expect_detector detect_go subtest-skip 2 '{"Action":"skip","Package":"p","Test":"TestAuthorizeStart/rejects_unknown_client"}
+{"Action":"pass","Package":"p","Test":"TestAuthorizeStart"}'
+	expect_detector detect_go zero 3 '{"Action":"pass","Package":"p"}'
+	expect_detector detect_go no-tests 3 '{"Action":"output","Package":"p","Output":"testing: warning: no tests to run\n"}
+{"Action":"pass","Package":"p"}'
+	expect_detector detect_go nonjson 4 '{"Action":"pass",'
+	REQUIRE_TESTS="TestOIDCTracerSmoke TestPHPMethodMap" expect_detector detect_go missing-named 5 \
+		'{"Action":"pass","Package":"p","Test":"TestOIDCTracerSmoke"}'
+	REQUIRE_TESTS="TestKeyRing" expect_detector detect_go prefix-is-not-the-test 5 \
+		'{"Action":"pass","Package":"p","Test":"TestKeyRingPreviousAppKey"}'
+	REQUIRE_TESTS="TestKeyRing" expect_detector detect_go subtest-is-not-the-test 5 \
+		'{"Action":"pass","Package":"p","Test":"TestOuter/TestKeyRing"}
+{"Action":"pass","Package":"p","Test":"TestOther"}'
+
+	# The NOT RUN rules, on a faked host: a docker binary that never answers,
+	# and an OAuth server plugin whose flows carry no recording.
+	local tmp
+	tmp="$(mktemp -d)"
+	mkdir -p "$tmp/bin" "$tmp/plugin/testdata/parity/flows"
+	printf '#!/bin/sh\nexit 1\n' >"$tmp/bin/docker"
+	chmod +x "$tmp/bin/docker"
+	printf 'version: 1\nsteps:\n  - id: a\n    request:\n      method: GET\n      path: "/"\n' >"$tmp/plugin/testdata/parity/flows/a.yaml"
+	expect_mode docker-not-run 0 "NOT RUN docker" --docker-gate PATH="$tmp/bin:$PATH" PHASE194_REQUIRE_DOCKER=0
+	expect_mode docker-required 1 "FAIL docker" --docker-gate PATH="$tmp/bin:$PATH" PHASE194_REQUIRE_DOCKER=1
+	expect_mode docker-stage-needs-daemon 1 "needs a reachable Docker daemon" --docker PATH="$tmp/bin:$PATH"
+	expect_mode parity-not-run 0 "NOT RUN parity: D-14 unproven" --parity OAUTHSERVER_PLUGIN="$tmp/plugin" PHASE194_REQUIRE_PARITY=0
+	expect_mode parity-required 1 "PHASE194_REQUIRE_PARITY=1" --parity OAUTHSERVER_PLUGIN="$tmp/plugin" PHASE194_REQUIRE_PARITY=1
+	if parity_recorded "$tmp/plugin/testdata/parity/flows"; then
+		rm -rf "$tmp"
+		echo "refuse: self-test parity_recorded accepted a spec flow without responses" >&2
+		return 1
+	fi
+	printf '    response:\n      status: 200\n' >>"$tmp/plugin/testdata/parity/flows/a.yaml"
+	if ! parity_recorded "$tmp/plugin/testdata/parity/flows"; then
+		rm -rf "$tmp"
+		echo "refuse: self-test parity_recorded missed a recorded flow" >&2
+		return 1
+	fi
+	rm -rf "$tmp"
+
+	# The additive check refuses a removed export and accepts additions.
+	local diff_bad diff_ok
+	diff_bad=$'--- a/classes/x.go\n+++ b/classes/x.go\n-func RequestUser(r *http.Request) (*User, error) {\n+func requestUser(r *http.Request) (*User, error) {'
+	diff_ok=$'--- a/classes/x.go\n+++ b/classes/x.go\n+func AvatarURL(u *User, size int) string {\n-func helper() {}\n-\t// func Old() is gone'
+	if [[ -z "$(removed_exports <<<"$diff_bad")" ]]; then
+		echo "refuse: self-test removed_exports missed a removed exported func" >&2
+		return 1
+	fi
+	if [[ -n "$(removed_exports <<<"$diff_ok")" ]]; then
+		echo "refuse: self-test removed_exports refused an additive diff" >&2
+		return 1
+	fi
+	for line in '-type DeactivatingEvent struct {' '-func (u *User) AvatarURL(size int) string {' '-func (User) Name() string {'; do
+		if [[ -z "$(removed_exports <<<"$line")" ]]; then
+			echo "refuse: self-test removed_exports missed: $line" >&2
+			return 1
+		fi
+	done
+
+	local mode
+	for mode in self-test go plugin userplugin fonoteka docker parity docs all; do
+		grep -q -- "^	--$mode" "${BASH_SOURCE[0]}" || {
+			echo "refuse: missing mode --$mode" >&2
+			return 1
+		}
+	done
+	echo "phase19.4 self-test passed"
+}
+
+run_go() {
+	go_vet "$ROOT" ./...
+	go_short "$ROOT"
+	go_named "$ROOT" ./modules/wristband -short "${WRISTBAND_TESTS[@]}"
+	go_named "$ROOT" ./modules/tide -short "${TIDE_TESTS[@]}"
+	echo "phase19.4 go passed"
+}
+
+run_plugin() {
+	require_dir "$OAUTHSERVER_PLUGIN" "OAuth server plugin"
+	go_vet "$OAUTHSERVER_PLUGIN" ./...
+	# The Docker suites skip here and run by name in the docker stage.
+	go_short "$OAUTHSERVER_PLUGIN"
+	go_named "$OAUTHSERVER_PLUGIN" . -short "${PLUGIN_TESTS[@]}"
+	if ((${#PLUGIN_CONSOLE_TESTS[@]})); then
+		go_named "$OAUTHSERVER_PLUGIN" ./console -short "${PLUGIN_CONSOLE_TESTS[@]}"
+	fi
+	echo "phase19.4 plugin passed"
+}
+
+# removed_exports reads a unified diff and prints every removed line that
+# declares an exported func, method or type.
+removed_exports() {
+	grep -E '^-(func ([A-Z]|\([^)]*\) [A-Z])|type [A-Z])' | grep -vE '^--- ' || true
+}
+
+run_userplugin() {
+	require_dir "$USER_PLUGIN" "user plugin"
+	require_dir "$FONOTEKA" "application workspace"
+	go_vet "$FONOTEKA" ./plugins/golem15/user/...
+	go_short "$FONOTEKA" ./plugins/golem15/user/...
+	if ((${#USER_CLASSES_TESTS[@]})); then
+		go_named "$FONOTEKA" ./plugins/golem15/user/classes -short "${USER_CLASSES_TESTS[@]}"
+	fi
+	if ((${#USER_ROOT_TESTS[@]})); then
+		go_named "$FONOTEKA" ./plugins/golem15/user -short "${USER_ROOT_TESTS[@]}"
+	fi
+	# D-05: additive only. git's status is captured before any filtering, so
+	# an unknown base or a broken checkout fails here instead of reading as
+	# an empty diff.
+	local diff rc=0 removed
+	diff="$(git -C "$USER_PLUGIN" diff "$USER_BASE" -- '*.go' ':(exclude)*_test.go' 2>&1)" || rc=$?
+	if [[ "$rc" -ne 0 ]]; then
+		printf '%s\n' "$diff" | tail -n 5 >&2
+		echo "refuse: git diff $USER_BASE in $USER_PLUGIN failed (exit $rc)" >&2
+		return 1
+	fi
+	removed="$(removed_exports <<<"$diff")"
+	if [[ -n "$removed" ]]; then
+		printf '%s\n' "$removed" >&2
+		echo "refuse: the user plugin removed or changed exported declarations since $USER_BASE (D-05: additive only)" >&2
+		return 1
+	fi
+	echo "additive: no exported func, method or type removed from the user plugin since $USER_BASE ($(grep -cE '^\+(func|type) ' <<<"$diff" || true) declarations added)"
+	echo "phase19.4 userplugin passed"
+}
+
+run_fonoteka() {
+	require_dir "$FONOTEKA" "application workspace"
+	go_vet "$FONOTEKA" ./... ./plugins/golem15/fono""teka/...
+	go_short "$FONOTEKA" ./plugins/golem15/fono""teka/...
+	go_named "$FONOTEKA" ./plugins/golem15/fono""teka -short "${APP_OAUTH_TESTS[@]}"
+	echo "phase19.4 fonoteka passed"
+}
+
+docker_up() {
+	command -v docker >/dev/null 2>&1 && docker info >/dev/null 2>&1
+}
+
+run_docker() {
+	if ! docker_up; then
+		echo "refuse: the docker stage needs a reachable Docker daemon (testcontainers); run it on a Docker host" >&2
+		return 1
+	fi
+	require_dir "$OAUTHSERVER_PLUGIN" "OAuth server plugin"
+	require_dir "$FONOTEKA" "application workspace"
+	go_named "$OAUTHSERVER_PLUGIN" . "-timeout 30m" "${DOCKER_PLUGIN_TESTS[@]}"
+	if ((${#DOCKER_PLUGIN_CONSOLE_TESTS[@]})); then
+		go_named "$OAUTHSERVER_PLUGIN" ./console "-timeout 20m" "${DOCKER_PLUGIN_CONSOLE_TESTS[@]}"
+	fi
+	if ((${#DOCKER_USER_CLASSES_TESTS[@]})); then
+		go_named "$FONOTEKA" ./plugins/golem15/user/classes "-timeout 20m" "${DOCKER_USER_CLASSES_TESTS[@]}"
+	fi
+	if ((${#DOCKER_USER_ROOT_TESTS[@]})); then
+		go_named "$FONOTEKA" ./plugins/golem15/user "-timeout 20m" "${DOCKER_USER_ROOT_TESTS[@]}"
+	fi
+	go_named "$FONOTEKA" ./plugins/golem15/fono""teka "-timeout 20m" "${DOCKER_APP_OAUTH_TESTS[@]}"
+	echo "phase19.4 docker passed"
+}
+
+# docker_gate is the docker step of --all: run the stage when a daemon
+# answers, fail with PHASE194_REQUIRE_DOCKER=1, print NOT RUN otherwise.
+docker_gate() {
+	if docker_up; then
+		if bash "${BASH_SOURCE[0]}" --docker; then
+			echo "PASS docker"
+			return 0
+		fi
+		echo "FAIL docker"
+		return 1
+	fi
+	if [[ "${PHASE194_REQUIRE_DOCKER:-0}" == "1" ]]; then
+		echo "FAIL docker: no reachable Docker daemon and PHASE194_REQUIRE_DOCKER=1"
+		return 1
+	fi
+	cat >&2 <<'EOF'
+************************************************************************
+NOT RUN docker: no reachable Docker daemon on this host.
+The testcontainers suites (Postgres) of the OAuth server plugin, the user
+plugin and the application did NOT run. Run on a Docker host before
+/msd-verify-work:
+  bash scripts/check-phase19.4.sh docker
+************************************************************************
+EOF
+	echo "NOT RUN docker (Docker-host only; see the notice above)"
+}
+
+# parity_recorded DIR is true when any flow under DIR carries a recorded
+# response (summer parity:record writes one per step).
+parity_recorded() {
+	local dir="$1"
+	[[ -d "$dir" ]] || return 1
+	grep -qE '^[[:space:]]+response:' "$dir"/*.yaml 2>/dev/null
+}
+
+run_parity() {
+	local flows="$OAUTHSERVER_PLUGIN/testdata/parity/flows"
+	require_dir "$flows" "parity flows"
+	if parity_recorded "$flows"; then
+		if ! docker_up; then
+			echo "refuse: the parity flows are recorded and their replay needs a reachable Docker daemon" >&2
+			return 1
+		fi
+		PHASE194_REQUIRE_PARITY=1 go_named "$OAUTHSERVER_PLUGIN" . "-timeout 30m" "${PARITY_TESTS[@]}"
+		echo "PASS parity: the PHP recordings replay against the Go plugin (D-14)"
+		return 0
+	fi
+	if [[ "${PHASE194_REQUIRE_PARITY:-0}" == "1" ]]; then
+		echo "FAIL parity: no PHP recordings under $flows and PHASE194_REQUIRE_PARITY=1" >&2
+		return 1
+	fi
+	cat >&2 <<EOF
+************************************************************************
+NOT RUN parity: D-14 unproven. No PHP recordings under
+  $flows
+so TestPHPParityReplay and TestIDTokenShapeParity did not run. By the
+D-14 amendment of 2026-10-19 the recording is deferred to the cutover of
+the PHP reference site and does not hold this phase's verdict:
+  $PARITY_TODO
+PHASE194_REQUIRE_PARITY=1 makes this stage fail.
+************************************************************************
+EOF
+	echo "NOT RUN parity: D-14 unproven (no PHP recordings; deferred, see $PARITY_TODO)"
+}
+
+run_docs() {
+	local name
+	for name in "${DECISION_NAMES[@]}"; do
+		if ! grep -qF -- "$name" "$ROOT/$DECISION_NOTE"; then
+			echo "refuse: the decision note $DECISION_NOTE does not name $name" >&2
+			return 1
+		fi
+	done
+	echo "note: $DECISION_NOTE names ${DECISION_NAMES[*]}"
+	go_named "$ROOT" ./cmd/summer "" TestDocsTree
+	(cd "$ROOT" && go run ./cmd/summer docs:build --check)
+	require_dir "$OAUTHSERVER_PLUGIN" "OAuth server plugin"
+	local pattern hits files=()
+	pattern="$(IFS='|'; echo "${APP_NAMES[*]}")"
+	while IFS= read -r -d '' f; do
+		files+=("$f")
+	done < <(find "$ROOT/modules/wristband" -type f -name '*.go' ! -name '*_test.go' -print0)
+	files+=("$ROOT/modules/wristband/README.md" "$ROOT/docs/services/oauth-server.md")
+	while IFS= read -r -d '' f; do
+		files+=("$f")
+	done < <(find "$OAUTHSERVER_PLUGIN" -type f \( -name '*.go' -o -name '*.md' -o -name '*.yaml' -o -name '*.tmpl' -o -name '*.htm' \) ! -path '*/.git/*' -print0)
+	hits="$(grep -inHE "$pattern" "${files[@]}" || true)"
+	if [[ -n "$hits" ]]; then
+		printf '%s\n' "$hits" | head -n 20 >&2
+		echo "refuse: a wristband source, the OAuth server docs page or a plugin file names a consuming application" >&2
+		return 1
+	fi
+	echo "names: ${#files[@]} files checked, no consuming application named"
+	echo "phase19.4 docs passed"
+}
+
+run_all() {
+	local stage
+	for stage in self-test go plugin userplugin fonoteka docs; do
+		if bash "${BASH_SOURCE[0]}" "--$stage"; then
+			echo "PASS $stage"
+		else
+			echo "FAIL $stage"
+			exit 1
+		fi
+	done
+	docker_gate || exit 1
+	if bash "${BASH_SOURCE[0]}" --parity; then
+		:
+	else
+		echo "FAIL parity"
+		exit 1
+	fi
+	echo "Phase 19.4 gate passed"
+}
+
+case "${1:---all}" in
+	--self-test | self-test) run_self_test ;;
+	--go | go) run_go ;;
+	--plugin | plugin) run_plugin ;;
+	--userplugin | userplugin) run_userplugin ;;
+	--fonoteka | fonoteka) run_fonoteka ;;
+	--docker | docker) run_docker ;;
+	--docker-gate) docker_gate ;;
+	--parity | parity) run_parity ;;
+	--docs | docs) run_docs ;;
+	--all | all) run_all ;;
+	*) usage ;;
+esac