diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 8ee47b14..774495a5 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -2698,9 +2698,11 @@ jobs:
               ;;
             compatibility)
               test -n "$PREVIOUS_STABLE"
-              ./scripts/policy/check-command-compatibility.sh \
+              "$GITHUB_WORKSPACE/tmp/trusted-release-tooling/scripts/release/check-release-compatibility.sh" \
+                --repo-root "$GITHUB_WORKSPACE" \
                 --base-ref HEAD \
-                --stable-ref "$PREVIOUS_STABLE"
+                --stable-ref "$PREVIOUS_STABLE" \
+                --candidate-ref HEAD
               ;;
             e2e)
               bash scripts/dev/test-multi-profile-e2e.sh
diff --git a/docs/cli-interface-flag-migrations.md b/docs/cli-interface-flag-migrations.md
index 60c5b684..81477cd5 100644
--- a/docs/cli-interface-flag-migrations.md
+++ b/docs/cli-interface-flag-migrations.md
@@ -68,6 +68,17 @@ optional bool legacy flag，不能隐藏仍由 Cobra hard-required 的参数。
 `replacement_constant.value` 与 legacy `no_opt` 都必须是 `true`；negative flag、默认即
 `true` 或固定 `false` 的语义不在本轮证明范围，必须另行设计，不能借本清单放行。
 
+如果 `command_move` 的参数 `from` 在更早 stable 中仍使用另一历史名称，Schema adapter
+只能把同一 legacy command 上、已经由 base-owned lifecycle 返回且
+`state=consumed` 的 flag rename 回执作为前驱边。例如
+`group → conversation-id` 与 `conversation-id → open-topic-id` 可以组合，但不能把
+candidate 自增的 pending 记录、其他命令的同名参数、参数概念词典或 CLI alias 当作证据。
+首次消费 pending command 回执时，merge-base 的 normalized Schema 必须真实发布中间参数，
+并逐跳验证参数签名和 constraints；command 回执合入为 consumed 后，中间 Schema 已从 main
+消失，此时保留的两份 consumed 回执可继续对 stable 做受限重放，直到 stable 也达到 after
+并按 lifecycle 清理。两种阶段都拒绝残留 predecessor/intermediate、字段漂移、环、分叉、
+target 碰撞或 primary path/tool identity 不唯一；positionals 不在该组合授权面内。
+
 `replacement_constant` 不是清单自报即可成立的例外。after 阶段的 Interface Snapshot
 必须从 replacement 命令的同一份框架运行时声明中捕获完全一致的 property/value，缺失、
 值不符或额外常量都会使 lifecycle 落入 partial。对于 #1054，`dws chat topic create`
diff --git a/docs/releasing.md b/docs/releasing.md
index 428cdbcc..c8d6c702 100644
--- a/docs/releasing.md
+++ b/docs/releasing.md
@@ -23,7 +23,7 @@
 
 `plan` 是纯只读操作，不创建 tag、预留版本号或生成包。CHANGELOG 合入期间若另一个发布先占用了该版本，`publish` 会重新分配并因 CHANGELOG 章节不匹配而拒绝，需要重新 plan。`publish` 会先再次确认 dispatch SHA 仍是当前 `main`、Code Admission 和平台治理均通过，再由唯一的 write job 使用 GitHub API 原子创建 annotated tag；同一次 run 随即进入既有的跨平台构建、GitHub/npm、可选 OSS/Gitee 发布和 Homebrew 直交付 DAG。内置 `GITHUB_TOKEN` 创建的 tag 不依赖第二条 workflow 被再次触发。
 
-为缩短封板前后的关键路径，`publish` 的只读版本规划会与平台治理检查并行，seal 仍严格等待二者成功；plan 在 candidate annotated tag 上验证过的 contract 和 stable/beta baseline 会绑定进 seal，并由 seal 后的 tag authority 检查复用。Code Admission 状态与 immutable-releases 治理仍会在 seal 后再次读取，避免 preflight 与发布之间的状态变化被忽略。随后三类只读门禁（release automation、命令兼容性、multi-profile E2E）与 GoReleaser 构建并行；Node/archive 等仅供后处理使用的工具也延后到构建完成后安装。并行和已验证结果复用只改变调度，不降低发布门禁：任何一条验证失败都会阻止 GitHub Release、npm、镜像和 Homebrew 发布，delivery proof 也要求三条验证 job 全部成功。
+为缩短封板前后的关键路径，`publish` 的只读版本规划会与平台治理检查并行，seal 仍严格等待二者成功；plan 在 candidate annotated tag 上验证过的 contract 和 stable/beta baseline 会绑定进 seal，并由 seal 后的 tag authority 检查复用。Code Admission 状态与 immutable-releases 治理仍会在 seal 后再次读取，避免 preflight 与发布之间的状态变化被忽略。随后三类只读门禁（release automation、CLI 与 Schema 兼容性、multi-profile E2E）与 GoReleaser 构建并行；Node/archive 等仅供后处理使用的工具也延后到构建完成后安装。并行和已验证结果复用只改变调度，不降低发布门禁：任何一条验证失败都会阻止 GitHub Release、npm、镜像和 Homebrew 发布，delivery proof 也要求三条验证 job 全部成功。
 
 OSS 镜像默认不参与发布 DAG，适用于尚未创建 Bucket 的仓库。云端封板会把当时的仓库变量 `ENABLE_OSS_MIRROR=true` 记录为不可变 tag 元数据 `OSS-Mirror: enabled`，否则记录为 `deferred`；后续发布和撤回只读取该 sealed policy，不读取变量的当前值。`enabled` 继续对缺失凭据、无效 Bucket、上传、pointer 和撤回失败保持 fail-closed；`deferred` 明确跳过不存在的渠道。为避免补发后撤回遗漏，deferred 版本暂不接受 `repair_oss_version`，启用 OSS 只影响后续新 tag，直到补齐可审计的不可变 repair 证明。
 
@@ -102,7 +102,7 @@ fragments，然后停止。审阅生成内容并通过唯一的 release-seal PR
 dws-release v1.2.3-beta.1
 ```
 
-预检包含测试、策略检查、旧正式版命令树兼容检查、全平台打包、npm 安装验证，以及 macOS 环境下的 Homebrew 安装验证。它还会从默认分支触发一次无发布权限的 `Release governance preflight`，用正式流水线相同的身份检查该精确 commit 的九个 Code Admission context 和 immutable releases。通过后回到上述 Actions 页面选择 beta 和 `release_operation=publish`；云端会重新绑定当前 `main`，然后直接进入 beta 自动发布，不需要人工审批或输入确认短语。
+预检包含测试、策略检查、旧正式版 CLI 与 Schema 双基线兼容检查、全平台打包、npm 安装验证，以及 macOS 环境下的 Homebrew 安装验证。它还会从默认分支触发一次无发布权限的 `Release governance preflight`，用正式流水线相同的身份检查该精确 commit 的九个 Code Admission context 和 immutable releases。通过后回到上述 Actions 页面选择 beta 和 `release_operation=publish`；云端会重新绑定当前 `main`，然后直接进入 beta 自动发布，不需要人工审批或输入确认短语。
 
 ## 正式发布
 
@@ -147,7 +147,7 @@ fragment，写入唯一版本章节后移动到 `.changes/released/<version>/`
 
 - 只接受 `vX.Y.Z-beta.N` 和 `vX.Y.Z`，且新版本必须高于上一正式版。这里的“上一正式版”必须同时具备公开非草稿 GitHub Release 和同 tag/commit 的成功 Release workflow；只有 tag、没有交付成功的孤儿版本会阻断后续发布，要求走机器核验恢复补齐。云端 tag 会固定 `Release-Run`、requester、commit 和版本分配指纹，交付验证按该精确 run/attempt 及完整 job graph 取证，不接受任意 `workflow_dispatch`。历史版本若曾通过专用 recovery workflow 完成交付，只能使用仓库内 `delivered-stable-recoveries.json` 中精确到 tag、commit、run、workflow SHA 与 attempt 的 reviewed 证据。
 - tag 必须由云端 seal job 创建为 annotated tag；封板提交必须已通过 PR 合入并包含在远端 `main` 历史中。流水线允许其后 `main` 继续前进，但始终要求封板提交位于 `main` 历史中。
-- 日常 CI 和发布前都会对比“最新已交付正式版”的完整命令树；若长时间预检期间该 baseline 发生变化，会针对新的 baseline 重新比较。
+- 日常 CI 和发布前都会对比“最新已交付正式版”的完整 CLI 与 Schema 契约；若长时间预检期间该 baseline 发生变化，会针对新的 baseline 重新比较。
 - GoReleaser 只构建；Darwin 重签、checksums 重算和 npm 安装验证通过后，才统一上传 GitHub Release 的最终产物。
 - 六个平台归档会逐个解包并核验二进制内嵌版本；公开资产集合、checksums 集合和 npm tarball integrity 都必须精确一致。npm tarball 固定由 npm `10.9.2` 打包，避免重跑时因 runner 自带 npm 漂移产生不同字节。
 - stable 发布到 npm `latest`；prerelease 发布到 npm `beta`。启用 `ENABLE_OSS_MIRROR=true` 后，stable 同步 OSS `latest.txt` 和共享安装脚本，prerelease 只同步 OSS `beta.txt`，不会覆盖稳定入口。
diff --git a/scripts/policy/check-authoritative-schema-compatibility.sh b/scripts/policy/check-authoritative-schema-compatibility.sh
index 45441cfd..f7a5b5b3 100755
--- a/scripts/policy/check-authoritative-schema-compatibility.sh
+++ b/scripts/policy/check-authoritative-schema-compatibility.sh
@@ -403,6 +403,11 @@ CANDIDATE_RAW="$TMP_ROOT/candidate-schema.json"
 	go build -o "$CANDIDATE_BIN" ./cmd
 )
 
+CHECKER_SUPPORTS_MIGRATION_BASE_SCHEMA=false
+if "$CHECKER" --help 2>&1 | grep -Fq -- 'migration-base-schema'; then
+	CHECKER_SUPPORTS_MIGRATION_BASE_SCHEMA=true
+fi
+
 mkdir -p "$TMP_ROOT/base-home" "$TMP_ROOT/stable-home" "$TMP_ROOT/candidate-home"
 HOME="$TMP_ROOT/base-home" DWS_LANG=zh \
 	"$BASE_BIN" schema --all --format json >"$BASE_RAW"
@@ -468,23 +473,22 @@ check_with_migrations() {
 	historical_kind="$1"
 	historical_ref="$2"
 	historical_baseline="$3"
+	set -- \
+		--approved-flag-migrations "$APPROVED_MANIFEST" \
+		--candidate-flag-migrations "$CANDIDATE_MANIFEST" \
+		--migration-current-snapshot "$CURRENT_INTERFACE_SNAPSHOT" \
+		--migration-base-snapshot "$BASE_INTERFACE_SNAPSHOT" \
+		--migration-stable-snapshot "$STABLE_INTERFACE_SNAPSHOT"
 	if [ "$USE_COMMAND_MIGRATION_GOVERNANCE" = true ]; then
-		check_schema_contract "$historical_kind" "$historical_ref" "$historical_baseline" \
-			--approved-flag-migrations "$APPROVED_MANIFEST" \
-			--candidate-flag-migrations "$CANDIDATE_MANIFEST" \
+		set -- "$@" \
 			--approved-command-migrations "$APPROVED_COMMAND_MANIFEST" \
-			--candidate-command-migrations "$CANDIDATE_COMMAND_MANIFEST" \
-			--migration-current-snapshot "$CURRENT_INTERFACE_SNAPSHOT" \
-			--migration-base-snapshot "$BASE_INTERFACE_SNAPSHOT" \
-			--migration-stable-snapshot "$STABLE_INTERFACE_SNAPSHOT"
-	else
-		check_schema_contract "$historical_kind" "$historical_ref" "$historical_baseline" \
-			--approved-flag-migrations "$APPROVED_MANIFEST" \
-			--candidate-flag-migrations "$CANDIDATE_MANIFEST" \
-			--migration-current-snapshot "$CURRENT_INTERFACE_SNAPSHOT" \
-			--migration-base-snapshot "$BASE_INTERFACE_SNAPSHOT" \
-			--migration-stable-snapshot "$STABLE_INTERFACE_SNAPSHOT"
+			--candidate-command-migrations "$CANDIDATE_COMMAND_MANIFEST"
 	fi
+	if [ "$USE_COMMAND_MIGRATION_GOVERNANCE" = true ] &&
+		[ "$CHECKER_SUPPORTS_MIGRATION_BASE_SCHEMA" = true ]; then
+		set -- "$@" --migration-base-schema "$BASELINE"
+	fi
+	check_schema_contract "$historical_kind" "$historical_ref" "$historical_baseline" "$@"
 }
 
 check_with_migrations "PR merge-base" "$BASE_REF" "$BASELINE"
diff --git a/scripts/policy/schema-compat/command_migrations_test.go b/scripts/policy/schema-compat/command_migrations_test.go
index ada5dcc7..5c6f32fb 100644
--- a/scripts/policy/schema-compat/command_migrations_test.go
+++ b/scripts/policy/schema-compat/command_migrations_test.go
@@ -233,6 +233,53 @@ func TestCrossPlatformCoverageSchemaCommandMigrationNormalizationEdges(t *testin
 		t.Fatalf("constraint drift was hidden: %s", failures)
 	}
 
+	unchangedLegacyConstraints := cloneContract(current)
+	product = unchangedLegacyConstraints.Products["chat"]
+	tool = product.Tools["chat.move"]
+	tool.Constraints = baseline.Products["chat"].Tools["chat.move"].Constraints
+	product.Tools["chat.move"] = tool
+	unchangedLegacyConstraints.Products["chat"] = product
+	if _, err := normalizeSchemaCommandMigrations(baseline, unchangedLegacyConstraints, migrations); err == nil ||
+		!strings.Contains(err.Error(), "still reference legacy Schema constraint parameter") {
+		t.Fatalf("unchanged legacy constraints error=%v", err)
+	}
+
+	mixedLegacyConstraints := cloneContract(current)
+	product = mixedLegacyConstraints.Products["chat"]
+	tool = product.Tools["chat.move"]
+	tool.Constraints = `{"require_together":[["keep","new-id","old-id"]]}`
+	product.Tools["chat.move"] = tool
+	mixedLegacyConstraints.Products["chat"] = product
+	if _, err := normalizeSchemaCommandMigrations(baseline, mixedLegacyConstraints, migrations); err == nil ||
+		!strings.Contains(err.Error(), "still reference legacy Schema constraint parameter") {
+		t.Fatalf("mixed legacy constraints error=%v", err)
+	}
+
+	malformedHistoricalConstraints := cloneContract(baseline)
+	product = malformedHistoricalConstraints.Products["chat"]
+	tool = product.Tools["chat.move"]
+	tool.Constraints = "{"
+	product.Tools["chat.move"] = tool
+	malformedHistoricalConstraints.Products["chat"] = product
+	if _, err := normalizeSchemaCommandMigrations(malformedHistoricalConstraints, current, migrations); err == nil ||
+		!strings.Contains(err.Error(), "historical Schema constraints are not canonicalizable") {
+		t.Fatalf("malformed historical constraints error=%v", err)
+	}
+
+	malformedCurrentConstraints := cloneContract(current)
+	product = malformedCurrentConstraints.Products["chat"]
+	tool = product.Tools["chat.move"]
+	tool.Constraints = "{"
+	product.Tools["chat.move"] = tool
+	malformedCurrentConstraints.Products["chat"] = product
+	if _, err := normalizeSchemaCommandMigrations(baseline, malformedCurrentConstraints, migrations); err == nil ||
+		!strings.Contains(err.Error(), "current Schema constraints are not canonicalizable") {
+		t.Fatalf("malformed current constraints error=%v", err)
+	}
+	if source, found := migratedConstraintSourceParameter("{", map[string]string{"legacy": "canonical"}); found || source != "" {
+		t.Fatalf("malformed migrated constraint source = %q, %v", source, found)
+	}
+
 	extractionWrongSource := cloneContract(current)
 	product = extractionWrongSource.Products["chat"]
 	tool = product.Tools["chat.create_group"]
@@ -657,6 +704,508 @@ func TestCrossPlatformCoverageSchemaCommandMigrationLifecycleAndRun(t *testing.T
 	}
 }
 
+func TestCrossPlatformCoverageSchemaCommandMigrationComposesHistoricalFlagLineage(t *testing.T) {
+	directory := t.TempDir()
+	stableContract, baseContract, currentContract := schemaCommandLineageContracts()
+	baselinePath := filepath.Join(directory, "stable-schema.json")
+	baseSchemaPath := filepath.Join(directory, "base-schema.json")
+	currentPath := filepath.Join(directory, "current-schema.json")
+	approvedFlagPath := filepath.Join(directory, "approved-flags.json")
+	candidateFlagPath := filepath.Join(directory, "candidate-flags.json")
+	approvedCommandPath := filepath.Join(directory, "approved-commands.json")
+	candidateCommandPath := filepath.Join(directory, "candidate-commands.json")
+	currentSnapshotPath := filepath.Join(directory, "current-snapshot.json")
+	baseSnapshotPath := filepath.Join(directory, "base-snapshot.json")
+	stableSnapshotPath := filepath.Join(directory, "stable-snapshot.json")
+
+	writeSchemaContractFile(t, baselinePath, stableContract)
+	writeSchemaContractFile(t, baseSchemaPath, baseContract)
+	writeRawSchemaContractFile(t, currentPath, currentContract)
+	writeFlagMigrationManifestFile(t, approvedFlagPath, schemaCommandLineageFlagManifest())
+	writeFlagMigrationManifestFile(t, candidateFlagPath, schemaCommandLineageFlagManifest())
+	writeCommandMigrationManifestFile(t, approvedCommandPath, schemaCommandLineageManifest(interfacesnapshot.CommandMigrationPending))
+	writeCommandMigrationManifestFile(t, candidateCommandPath, schemaCommandLineageManifest(interfacesnapshot.CommandMigrationConsumed))
+	writeInterfaceSnapshotFile(t, currentSnapshotPath, schemaCommandLineageSnapshot(true, true))
+	writeInterfaceSnapshotFile(t, baseSnapshotPath, schemaCommandLineageSnapshot(true, false))
+	writeInterfaceSnapshotFile(t, stableSnapshotPath, schemaCommandLineageSnapshot(false, false))
+
+	args := []string{
+		"--check", baselinePath,
+		"--current", currentPath,
+		"--migration-base-schema", baseSchemaPath,
+		"--approved-flag-migrations", approvedFlagPath,
+		"--candidate-flag-migrations", candidateFlagPath,
+		"--approved-command-migrations", approvedCommandPath,
+		"--candidate-command-migrations", candidateCommandPath,
+		"--migration-current-snapshot", currentSnapshotPath,
+		"--migration-base-snapshot", baseSnapshotPath,
+		"--migration-stable-snapshot", stableSnapshotPath,
+	}
+	var stdout, stderr strings.Builder
+	if code := run(args, &stdout, &stderr); code != 0 {
+		t.Fatalf("pending command lineage code=%d stderr=%s", code, stderr.String())
+	}
+
+	withoutBaseSchema := append([]string(nil), args[:4]...)
+	withoutBaseSchema = append(withoutBaseSchema, args[6:]...)
+	stderr.Reset()
+	if code := run(withoutBaseSchema, &stdout, &stderr); code != 2 ||
+		!strings.Contains(stderr.String(), "requires --migration-base-schema") {
+		t.Fatalf("missing migration base Schema code=%d stderr=%q", code, stderr.String())
+	}
+	stderr.Reset()
+	if code := run([]string{
+		"--check", baselinePath,
+		"--current", currentPath,
+		"--migration-base-schema", baseSchemaPath,
+	}, &stdout, &stderr); code != 2 || !strings.Contains(stderr.String(), "requires both flag and command") {
+		t.Fatalf("orphan migration base Schema code=%d stderr=%q", code, stderr.String())
+	}
+	missingBaseSchema := append([]string(nil), args...)
+	missingBaseSchema[5] = filepath.Join(directory, "missing-base-schema.json")
+	stderr.Reset()
+	if code := run(missingBaseSchema, &stdout, &stderr); code != 2 ||
+		!strings.Contains(stderr.String(), "read migration merge-base Schema contract") {
+		t.Fatalf("unreadable migration base Schema code=%d stderr=%q", code, stderr.String())
+	}
+
+	// After the command move is merged, the merge-base Schema is already at the
+	// final name. The two consumed receipts must keep the stable lineage durable
+	// until the stable release itself reaches the after state.
+	writeSchemaContractFile(t, baseSchemaPath, currentContract)
+	writeCommandMigrationManifestFile(t, approvedCommandPath, schemaCommandLineageManifest(interfacesnapshot.CommandMigrationConsumed))
+	writeInterfaceSnapshotFile(t, baseSnapshotPath, schemaCommandLineageSnapshot(true, true))
+	stdout.Reset()
+	stderr.Reset()
+	if code := run(args, &stdout, &stderr); code != 0 {
+		t.Fatalf("consumed command lineage code=%d stderr=%s", code, stderr.String())
+	}
+}
+
+func TestCrossPlatformCoverageSchemaCommandMigrationLineageFailsClosed(t *testing.T) {
+	tests := []struct {
+		name         string
+		commandState string
+		mutate       func(*schemaContract, *schemaContract, *schemaContract, *[]interfacesnapshot.FlagMigration, *[]interfacesnapshot.CommandMigration)
+		want         string
+	}{
+		{
+			name:         "pending merge-base missing intermediate",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					delete(tool.Parameters, "conversation-id")
+				})
+			},
+			want: "merge-base Schema lacks intermediate parameter",
+		},
+		{
+			name:         "merge-base missing source tool",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				product := base.Products["chat"]
+				delete(product.Tools, "chat.list_topic_replies")
+				base.Products["chat"] = product
+			},
+			want: "merge-base Schema lacks source tool",
+		},
+		{
+			name:         "pending merge-base parameter drift",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationParameter(base, "chat.list_topic_replies", "conversation-id", func(parameter *parameterSchema) {
+					parameter.Property = "differentProperty"
+				})
+			},
+			want: "changed a non-migration field",
+		},
+		{
+			name:         "pending merge-base wrong path",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.PrimaryCLIPath = "chat unrelated"
+				})
+			},
+			want: "merge-base Schema source tool has primary_cli_path",
+		},
+		{
+			name:         "pending merge-base already publishes final",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Parameters["open-topic-id"] = tool.Parameters["conversation-id"]
+				})
+			},
+			want: "already publishes final parameter",
+		},
+		{
+			name:         "pending flag receipt",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, _, _ *schemaContract, flags *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				(*flags)[0].State = interfacesnapshot.FlagMigrationPending
+			},
+			want: "requires a consumed flag migration receipt",
+		},
+		{
+			name:         "flag receipt belongs to another command",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, _, _ *schemaContract, flags *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				(*flags)[0].Command = "dws chat message other"
+			},
+			want: `historical Schema tool lacks parameter "conversation-id"`,
+		},
+		{
+			name:         "current retains predecessor",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(stable, _, current *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(current, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Parameters["group"] = stable.Products["chat"].Tools["chat.list_topic_replies"].Parameters["group"]
+				})
+			},
+			want: "current Schema still publishes predecessor parameter",
+		},
+		{
+			name:         "pending current constraints retain predecessor",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, _, current *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(current, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Constraints = `{"require_together":[["group","open-conv-thread-id","open-topic-id"]]}`
+				})
+			},
+			want: "current Schema constraints still reference predecessor parameter",
+		},
+		{
+			name:         "consumed current constraints retain predecessor",
+			commandState: interfacesnapshot.CommandMigrationConsumed,
+			mutate: func(_, _, current *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(current, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Constraints = `{"require_together":[["group","open-conv-thread-id","open-topic-id"]]}`
+				})
+			},
+			want: "current Schema constraints still reference predecessor parameter",
+		},
+		{
+			name:         "current retains intermediate",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, current *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(current, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Parameters["conversation-id"] = base.Products["chat"].Tools["chat.list_topic_replies"].Parameters["conversation-id"]
+				})
+			},
+			want: `still publishes legacy Schema parameter "conversation-id"`,
+		},
+		{
+			name:         "consumed merge-base final drift",
+			commandState: interfacesnapshot.CommandMigrationConsumed,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationParameter(base, "chat.list_topic_replies", "open-topic-id", func(parameter *parameterSchema) {
+					parameter.Required = false
+				})
+			},
+			want: "changed a non-name field",
+		},
+		{
+			name:         "consumed merge-base wrong path",
+			commandState: interfacesnapshot.CommandMigrationConsumed,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.PrimaryCLIPath = "chat unrelated"
+				})
+			},
+			want: "consumed command migration",
+		},
+		{
+			name:         "consumed merge-base missing final",
+			commandState: interfacesnapshot.CommandMigrationConsumed,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					delete(tool.Parameters, "open-topic-id")
+				})
+			},
+			want: "merge-base Schema lacks final parameter",
+		},
+		{
+			name:         "consumed merge-base retains intermediate",
+			commandState: interfacesnapshot.CommandMigrationConsumed,
+			mutate: func(stable, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Parameters["conversation-id"] = stable.Products["chat"].Tools["chat.list_topic_replies"].Parameters["group"]
+				})
+			},
+			want: "still publishes intermediate parameter",
+		},
+		{
+			name:         "pending constraints drift",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Constraints = `{"require_one_of":[["conversation-id"]]}`
+				})
+			},
+			want: "changed merge-base Schema constraints",
+		},
+		{
+			name:         "pending current keeps intermediate constraints",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, current *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(current, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Constraints = base.Products["chat"].Tools["chat.list_topic_replies"].Constraints
+				})
+			},
+			want: "still reference legacy Schema constraint parameter",
+		},
+		{
+			name:         "merge-base retains predecessor",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(stable, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Parameters["group"] = stable.Products["chat"].Tools["chat.list_topic_replies"].Parameters["group"]
+				})
+			},
+			want: "merge-base Schema still publishes predecessor parameter",
+		},
+		{
+			name:         "historical constraints malformed",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(stable, _, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(stable, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Constraints = "not-json"
+				})
+			},
+			want: "historical Schema constraints are not canonicalizable",
+		},
+		{
+			name:         "merge-base constraints malformed",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Constraints = "not-json"
+				})
+			},
+			want: "merge-base Schema constraints are not canonicalizable",
+		},
+		{
+			name:         "consumed constraints drift",
+			commandState: interfacesnapshot.CommandMigrationConsumed,
+			mutate: func(_, base, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(base, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Constraints = `{"require_one_of":[["open-topic-id"]]}`
+				})
+			},
+			want: "changed merge-base Schema constraints",
+		},
+		{
+			name:         "target collision",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(stable, _, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				mutateSchemaCommandMigrationTool(stable, "chat.list_topic_replies", func(tool *toolSchema) {
+					tool.Parameters["open-topic-id"] = tool.Parameters["group"]
+				})
+			},
+			want: "target \"open-topic-id\" already exists",
+		},
+		{
+			name:         "lineage cycle",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, _, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, commands *[]interfacesnapshot.CommandMigration) {
+				(*commands)[0].Schema.Parameters[0].To = "group"
+			},
+			want: "lineage cycle",
+		},
+		{
+			name:         "unsupported command receipt state",
+			commandState: "unknown",
+			mutate: func(_, _, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+			},
+			want: "unsupported lineage state",
+		},
+		{
+			name:         "duplicate historical path",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(stable, _, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, _ *[]interfacesnapshot.CommandMigration) {
+				product := stable.Products["chat"]
+				product.Tools["chat.duplicate"] = product.Tools["chat.list_topic_replies"]
+				stable.Products["chat"] = product
+			},
+			want: "matches 2 historical Schema tools",
+		},
+		{
+			name:         "source tool fork",
+			commandState: interfacesnapshot.CommandMigrationPending,
+			mutate: func(_, _, _ *schemaContract, _ *[]interfacesnapshot.FlagMigration, commands *[]interfacesnapshot.CommandMigration) {
+				fork := (*commands)[0]
+				fork.Legacy.Command = "dws chat message fork"
+				fork.Replacement.Command = "dws chat topic fork"
+				*commands = append(*commands, fork)
+			},
+			want: "fork Schema source tool",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			stable, baseBefore, current := schemaCommandLineageContracts()
+			base := baseBefore
+			if test.commandState == interfacesnapshot.CommandMigrationConsumed {
+				base = cloneContract(current)
+			}
+			flags := append([]interfacesnapshot.FlagMigration(nil), schemaCommandLineageFlagManifest().Migrations...)
+			commands := append([]interfacesnapshot.CommandMigration(nil), schemaCommandLineageManifest(test.commandState).Migrations...)
+			test.mutate(&stable, &base, &current, &flags, &commands)
+			if _, err := normalizeSchemaCommandMigrationLineage(stable, base, current, flags, commands); err == nil ||
+				!strings.Contains(err.Error(), test.want) {
+				t.Fatalf("lineage error=%v, want %q", err, test.want)
+			}
+		})
+	}
+}
+
+func TestCrossPlatformCoverageSchemaCommandMigrationLineagePreservesOrdinaryChecks(t *testing.T) {
+	stable, base, current := schemaCommandLineageContracts()
+	mutateSchemaCommandMigrationTool(&current, "chat.list_topic_replies", func(tool *toolSchema) {
+		tool.Positionals = []positionalSchema{{Name: "open-topic-id", Index: 0, Type: "string", Required: true}}
+	})
+	normalized, err := normalizeSchemaCommandMigrationLineage(
+		stable,
+		base,
+		current,
+		schemaCommandLineageFlagManifest().Migrations,
+		schemaCommandLineageManifest(interfacesnapshot.CommandMigrationPending).Migrations,
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if failures := strings.Join(checkCompatibility(normalized, current), "\n"); !strings.Contains(failures, "changed positionals") {
+		t.Fatalf("lineage hid positional drift: %s", failures)
+	}
+
+	// Multiple historical names may converge only when every predecessor carries
+	// the exact same contract and every receipt is already consumed.
+	stable, base, current = schemaCommandLineageContracts()
+	mutateSchemaCommandMigrationTool(&stable, "chat.list_topic_replies", func(tool *toolSchema) {
+		tool.Parameters["id"] = tool.Parameters["group"]
+	})
+	flags := schemaCommandLineageFlagManifest().Migrations
+	second := flags[0]
+	second.Legacy.Name = "id"
+	flags = append(flags, second)
+	normalized, err = normalizeSchemaCommandMigrationLineage(
+		stable,
+		base,
+		current,
+		flags,
+		schemaCommandLineageManifest(interfacesnapshot.CommandMigrationPending).Migrations,
+	)
+	if err != nil {
+		t.Fatalf("equivalent predecessor aliases should pass: %v", err)
+	}
+	if failures := checkCompatibility(normalized, current); len(failures) != 0 {
+		t.Fatalf("equivalent predecessor aliases remained incompatible: %v", failures)
+	}
+
+	mutateSchemaCommandMigrationParameter(&stable, "chat.list_topic_replies", "id", func(parameter *parameterSchema) {
+		parameter.Property = "differentProperty"
+	})
+	if _, err := normalizeSchemaCommandMigrationLineage(
+		stable,
+		base,
+		current,
+		flags,
+		schemaCommandLineageManifest(interfacesnapshot.CommandMigrationPending).Migrations,
+	); err == nil || !strings.Contains(err.Error(), "changed a non-migration field") {
+		t.Fatalf("drifted predecessor alias error=%v", err)
+	}
+}
+
+func TestCrossPlatformCoverageSchemaCommandMigrationLineageDefensiveEdges(t *testing.T) {
+	stable, base, current := schemaCommandLineageContracts()
+	flags := schemaCommandLineageFlagManifest().Migrations
+	commands := schemaCommandLineageManifest(interfacesnapshot.CommandMigrationPending).Migrations
+
+	flagExtraction := schemaCommandMigrationAuthorizations()[1]
+	if _, err := stageSchemaCommandMigrationPredecessors(stable, base, current, flags, []interfacesnapshot.CommandMigration{flagExtraction}); err != nil {
+		t.Fatalf("non-move command migration should be ignored: %v", err)
+	}
+
+	missingTool := cloneContract(stable)
+	product := missingTool.Products["chat"]
+	delete(product.Tools, "chat.list_topic_replies")
+	missingTool.Products["chat"] = product
+	if _, err := stageSchemaCommandMigrationPredecessors(missingTool, base, current, flags, commands); err != nil {
+		t.Fatalf("missing historical source should remain for the ordinary checker: %v", err)
+	}
+	if _, err := stageSchemaCommandMigrationPredecessors(current, current, current, flags, schemaCommandLineageManifest(interfacesnapshot.CommandMigrationConsumed).Migrations); err != nil {
+		t.Fatalf("already-after historical source should be a no-op: %v", err)
+	}
+	wrongPath := cloneContract(stable)
+	mutateSchemaCommandMigrationTool(&wrongPath, "chat.list_topic_replies", func(tool *toolSchema) {
+		tool.PrimaryCLIPath = "chat unrelated"
+	})
+	if _, err := stageSchemaCommandMigrationPredecessors(wrongPath, base, current, flags, commands); err != nil {
+		t.Fatalf("wrong historical path should remain for the command normalizer: %v", err)
+	}
+
+	bothNames := cloneContract(stable)
+	mutateSchemaCommandMigrationTool(&bothNames, "chat.list_topic_replies", func(tool *toolSchema) {
+		tool.Parameters["conversation-id"] = tool.Parameters["group"]
+	})
+	if _, err := stageSchemaCommandMigrationPredecessors(bothNames, base, current, flags, commands); err == nil ||
+		!strings.Contains(err.Error(), "publishes both predecessor") {
+		t.Fatalf("ambiguous predecessor error=%v", err)
+	}
+
+	duplicatePath := cloneContract(stable)
+	product = duplicatePath.Products["chat"]
+	product.Tools["chat.duplicate"] = product.Tools["chat.list_topic_replies"]
+	duplicatePath.Products["chat"] = product
+	if _, err := stageSchemaCommandMigrationPredecessors(duplicatePath, base, current, flags, commands); err == nil ||
+		!strings.Contains(err.Error(), "requires one exact historical Schema tool") {
+		t.Fatalf("duplicate primary path error=%v", err)
+	}
+
+	forkStable, forkBase, forkCurrent := schemaCommandLineageContracts()
+	mutateSchemaCommandMigrationTool(&forkBase, "chat.list_topic_replies", func(tool *toolSchema) {
+		tool.Parameters["other-mid"] = tool.Parameters["conversation-id"]
+	})
+	mutateSchemaCommandMigrationTool(&forkCurrent, "chat.list_topic_replies", func(tool *toolSchema) {
+		tool.Parameters["other-final"] = tool.Parameters["open-topic-id"]
+	})
+	forkFlags := append([]interfacesnapshot.FlagMigration(nil), flags...)
+	forkFlag := flags[0]
+	forkFlag.Canonical.Name = "other-mid"
+	forkFlags = append(forkFlags, forkFlag)
+	forkCommands := schemaCommandLineageManifest(interfacesnapshot.CommandMigrationPending).Migrations
+	forkCommands[0].Schema.Parameters = append(forkCommands[0].Schema.Parameters,
+		interfacesnapshot.CommandParameterMigration{From: "other-mid", To: "other-final"})
+	if _, err := stageSchemaCommandMigrationPredecessors(forkStable, forkBase, forkCurrent, forkFlags, forkCommands); err == nil ||
+		!strings.Contains(err.Error(), "forks Schema predecessor") {
+		t.Fatalf("forked predecessor error=%v", err)
+	}
+
+	cycleStable, cycleBase, _ := schemaCommandLineageContracts()
+	mutateSchemaCommandMigrationTool(&cycleStable, "chat.list_topic_replies", func(tool *toolSchema) {
+		tool.Parameters["id"] = tool.Parameters["group"]
+	})
+	mutateSchemaCommandMigrationTool(&cycleBase, "chat.list_topic_replies", func(tool *toolSchema) {
+		tool.Parameters["other-mid"] = tool.Parameters["conversation-id"]
+	})
+	cycleFlags := append([]interfacesnapshot.FlagMigration(nil), flags...)
+	cycleFlag := flags[0]
+	cycleFlag.Legacy.Name = "id"
+	cycleFlag.Canonical.Name = "other-mid"
+	cycleFlags = append(cycleFlags, cycleFlag)
+	cycleCommands := schemaCommandLineageManifest(interfacesnapshot.CommandMigrationPending).Migrations
+	cycleCommands[0].Schema.Parameters[0].To = "id"
+	cycleCommands[0].Schema.Parameters = append(cycleCommands[0].Schema.Parameters,
+		interfacesnapshot.CommandParameterMigration{From: "other-mid", To: "other-final"})
+	missingCurrent := schemaContract{Version: schemaContractVersion, Products: map[string]productSchema{}}
+	if _, err := stageSchemaCommandMigrationPredecessors(cycleStable, cycleBase, missingCurrent, cycleFlags, cycleCommands); err == nil ||
+		!strings.Contains(err.Error(), "lineage cycle") {
+		t.Fatalf("cross-lineage cycle error=%v", err)
+	}
+}
+
 func schemaCommandMigrationContract(after bool) schemaContract {
 	id := parameterSchema{Type: `"string"`, Property: "resourceId", Required: true, CLIRequired: true}
 	keep := parameterSchema{Type: `"string"`, Property: "keep"}
@@ -722,6 +1271,155 @@ func schemaCommandMigrationContract(after bool) schemaContract {
 	return schemaContract{Version: schemaContractVersion, Products: map[string]productSchema{"chat": {Tools: tools}}}
 }
 
+func schemaCommandLineageContracts() (schemaContract, schemaContract, schemaContract) {
+	conversation := parameterSchema{
+		Type:          `"string"`,
+		Property:      "openconversationId",
+		InterfaceType: "string",
+		Required:      true,
+		CLIRequired:   true,
+	}
+	topic := parameterSchema{
+		Type:          `"string"`,
+		Property:      "openConversationThreadId",
+		InterfaceType: "string",
+		Required:      true,
+		CLIRequired:   true,
+	}
+	tool := toolSchema{
+		PrimaryCLIPath: "chat message list-topic-replies",
+		InterfaceMode:  "mcp",
+		InterfaceRef:   `{"product_id":"im","rpc_name":"list_topic_replies"}`,
+		Availability:   "available",
+		Parameters: map[string]parameterSchema{
+			"group":    conversation,
+			"topic-id": topic,
+		},
+		Constraints:  `{"require_together":[["group","topic-id"]]}`,
+		Effect:       "read",
+		Risk:         "low",
+		Confirmation: "not_required",
+		Idempotency:  "idempotent",
+	}
+	stable := schemaContract{Version: schemaContractVersion, Products: map[string]productSchema{
+		"chat": {Tools: map[string]toolSchema{"chat.list_topic_replies": tool}},
+	}}
+
+	base := cloneContract(stable)
+	mutateSchemaCommandMigrationTool(&base, "chat.list_topic_replies", func(tool *toolSchema) {
+		delete(tool.Parameters, "group")
+		tool.Parameters["conversation-id"] = conversation
+		tool.Constraints = `{"require_together":[["conversation-id","topic-id"]]}`
+	})
+
+	current := cloneContract(base)
+	mutateSchemaCommandMigrationTool(&current, "chat.list_topic_replies", func(tool *toolSchema) {
+		delete(tool.Parameters, "conversation-id")
+		delete(tool.Parameters, "topic-id")
+		tool.Parameters["open-topic-id"] = conversation
+		tool.Parameters["open-conv-thread-id"] = topic
+		tool.PrimaryCLIPath = "chat topic list-replies"
+		tool.Constraints = `{"require_together":[["open-conv-thread-id","open-topic-id"]]}`
+	})
+	return stable, base, current
+}
+
+func schemaCommandLineageFlagManifest() interfacesnapshot.FlagMigrationManifest {
+	beforeCanonical := interfacesnapshot.FlagMigrationState{Present: true, Type: "string", Hidden: true, Scope: "local"}
+	afterCanonical := interfacesnapshot.FlagMigrationState{Present: true, Type: "string", Required: true, Scope: "local"}
+	return interfacesnapshot.FlagMigrationManifest{
+		Version: interfacesnapshot.FlagMigrationManifestVersion,
+		Migrations: []interfacesnapshot.FlagMigration{{
+			Command: "dws chat message list-topic-replies",
+			Legacy: interfacesnapshot.FlagMigrationSide{
+				Name:   "group",
+				Before: interfacesnapshot.FlagMigrationState{Present: true, Type: "string", Required: true, Scope: "local"},
+				After:  interfacesnapshot.FlagMigrationState{Present: true, Type: "string", Hidden: true, Scope: "local", AliasOf: "conversation-id"},
+			},
+			Canonical: interfacesnapshot.FlagMigrationSide{
+				Name:   "conversation-id",
+				Before: beforeCanonical,
+				After:  afterCanonical,
+			},
+			State:  interfacesnapshot.FlagMigrationConsumed,
+			Reason: "preserve the reviewed group to conversation-id lineage",
+		}},
+	}
+}
+
+func schemaCommandLineageManifest(state string) interfacesnapshot.CommandMigrationManifest {
+	return interfacesnapshot.CommandMigrationManifest{
+		Version: interfacesnapshot.CommandMigrationManifestVersion,
+		Migrations: []interfacesnapshot.CommandMigration{{
+			Kind: interfacesnapshot.CommandMigrationMove,
+			Legacy: interfacesnapshot.CommandMigrationSide{
+				Command: "dws chat message list-topic-replies",
+				Before:  interfacesnapshot.CommandMigrationState{Present: true, Runnable: true},
+				After:   interfacesnapshot.CommandMigrationState{Present: true, Runnable: true, Hidden: true},
+			},
+			Replacement: interfacesnapshot.CommandMigrationSide{
+				Command: "dws chat topic list-replies",
+				Before:  interfacesnapshot.CommandMigrationState{},
+				After:   interfacesnapshot.CommandMigrationState{Present: true, Runnable: true},
+			},
+			Schema: interfacesnapshot.CommandMigrationSchema{
+				ProductID:         "chat",
+				SourceToolID:      "chat.list_topic_replies",
+				ReplacementToolID: "chat.list_topic_replies",
+				Parameters: []interfacesnapshot.CommandParameterMigration{
+					{From: "conversation-id", To: "open-topic-id"},
+					{From: "topic-id", To: "open-conv-thread-id"},
+				},
+			},
+			State:  state,
+			Reason: "move topic reply listing while retaining the legacy command",
+		}},
+	}
+}
+
+func schemaCommandLineageSnapshot(flagAfter, commandAfter bool) interfacesnapshot.Snapshot {
+	legacyFlags := []interfacesnapshot.Flag{
+		{Name: "conversation-id", Type: "string", Hidden: true},
+		{Name: "group", Type: "string", Required: true},
+		{Name: "topic-id", Type: "string", Required: true},
+	}
+	if flagAfter {
+		legacyFlags[0].Hidden = false
+		legacyFlags[0].Required = true
+		legacyFlags[1].Required = false
+		legacyFlags[1].Hidden = true
+		legacyFlags[1].AliasOf = "conversation-id"
+	}
+	commands := []interfacesnapshot.Command{
+		{Path: "dws", Runnable: true, Aliases: []string{}, LocalFlags: []interfacesnapshot.Flag{}, InheritedFlags: []interfacesnapshot.Flag{}},
+		{
+			Path:           "dws chat message list-topic-replies",
+			Runnable:       true,
+			Aliases:        []string{},
+			LocalFlags:     legacyFlags,
+			InheritedFlags: []interfacesnapshot.Flag{},
+		},
+	}
+	if commandAfter {
+		commands[1].Hidden = true
+		commands = append(commands, interfacesnapshot.Command{
+			Path:           "dws chat topic list-replies",
+			Runnable:       true,
+			Aliases:        []string{},
+			LocalFlags:     []interfacesnapshot.Flag{},
+			InheritedFlags: []interfacesnapshot.Flag{},
+		})
+	}
+	return interfacesnapshot.Snapshot{
+		SchemaVersion: interfacesnapshot.SchemaVersion,
+		Rules: interfacesnapshot.Rules{
+			ExcludedCommandSubtrees: []string{"dws __complete", "dws __completeNoDesc", "dws completion", "dws help"},
+			ExcludedFlags:           []string{"help"},
+		},
+		Commands: commands,
+	}
+}
+
 func schemaCommandMigrationAuthorizations() []interfacesnapshot.CommandMigration {
 	return []interfacesnapshot.CommandMigration{
 		{
diff --git a/scripts/policy/schema-compat/main.go b/scripts/policy/schema-compat/main.go
index 7496d4f3..9aa151cc 100644
--- a/scripts/policy/schema-compat/main.go
+++ b/scripts/policy/schema-compat/main.go
@@ -87,6 +87,7 @@ func run(args []string, stdout, stderr io.Writer) int {
 	var normalizePath, checkPath, mergePath, currentPath string
 	var approvedFlagMigrationsPath, candidateFlagMigrationsPath string
 	var approvedCommandMigrationsPath, candidateCommandMigrationsPath string
+	var migrationBaseSchemaPath string
 	var migrationCurrentSnapshotPath, migrationBaseSnapshotPath, migrationStableSnapshotPath string
 	flags := flag.NewFlagSet("schema-compat", flag.ContinueOnError)
 	flags.SetOutput(stderr)
@@ -98,6 +99,7 @@ func run(args []string, stdout, stderr io.Writer) int {
 	flags.StringVar(&candidateFlagMigrationsPath, "candidate-flag-migrations", "", "detached candidate flag migration manifest")
 	flags.StringVar(&approvedCommandMigrationsPath, "approved-command-migrations", "", "base-owned approved command migration manifest")
 	flags.StringVar(&candidateCommandMigrationsPath, "candidate-command-migrations", "", "detached candidate command migration manifest")
+	flags.StringVar(&migrationBaseSchemaPath, "migration-base-schema", "", "normalized merge-base Schema contract used to verify cross-migration lineage")
 	flags.StringVar(&migrationCurrentSnapshotPath, "migration-current-snapshot", "", "current interface snapshot used for migration authorization")
 	flags.StringVar(&migrationBaseSnapshotPath, "migration-base-snapshot", "", "merge-base interface snapshot used for migration authorization")
 	flags.StringVar(&migrationStableSnapshotPath, "migration-stable-snapshot", "", "stable interface snapshot used for migration authorization")
@@ -149,6 +151,14 @@ func run(args []string, stdout, stderr io.Writer) int {
 		fmt.Fprintln(stderr, "Schema migration authorization is only valid with --check")
 		return 2
 	}
+	if flagMigrationPair && commandMigrationPair && migrationBaseSchemaPath == "" {
+		fmt.Fprintln(stderr, "combined Schema flag and command migration authorization requires --migration-base-schema")
+		return 2
+	}
+	if migrationBaseSchemaPath != "" && (!flagMigrationPair || !commandMigrationPair) {
+		fmt.Fprintln(stderr, "--migration-base-schema requires both flag and command migration manifest pairs")
+		return 2
+	}
 
 	if normalizePath != "" {
 		currentPath = normalizePath
@@ -175,8 +185,9 @@ func run(args []string, stdout, stderr io.Writer) int {
 			fmt.Fprintf(stderr, "read schema baseline: %v\n", err)
 			return 2
 		}
+		var flagMigrations []interfacesnapshot.FlagMigration
 		if flagMigrationPair {
-			migrations, err := authorizeSchemaFlagMigrations(
+			flagMigrations, err = authorizeSchemaFlagMigrations(
 				approvedFlagMigrationsPath,
 				candidateFlagMigrationsPath,
 				migrationCurrentSnapshotPath,
@@ -187,14 +198,9 @@ func run(args []string, stdout, stderr io.Writer) int {
 				fmt.Fprintf(stderr, "authorize Schema flag migrations: %v\n", err)
 				return 2
 			}
-			baseline, err = normalizeSchemaFlagMigrations(baseline, current, migrations)
-			if err != nil {
-				fmt.Fprintf(stderr, "normalize approved Schema flag migrations: %v\n", err)
-				return 2
-			}
 		}
 		if commandMigrationPair {
-			migrations, err := authorizeSchemaCommandMigrations(
+			commandMigrations, err := authorizeSchemaCommandMigrations(
 				approvedCommandMigrationsPath,
 				candidateCommandMigrationsPath,
 				migrationCurrentSnapshotPath,
@@ -205,11 +211,32 @@ func run(args []string, stdout, stderr io.Writer) int {
 				fmt.Fprintf(stderr, "authorize Schema command migrations: %v\n", err)
 				return 2
 			}
-			baseline, err = normalizeSchemaCommandMigrations(baseline, current, migrations)
+			if flagMigrationPair {
+				migrationBase, readErr := readContract(migrationBaseSchemaPath)
+				if readErr != nil {
+					fmt.Fprintf(stderr, "read migration merge-base Schema contract: %v\n", readErr)
+					return 2
+				}
+				baseline, err = normalizeSchemaCommandMigrationLineage(
+					baseline,
+					migrationBase,
+					current,
+					flagMigrations,
+					commandMigrations,
+				)
+			} else {
+				baseline, err = normalizeSchemaCommandMigrations(baseline, current, commandMigrations)
+			}
 			if err != nil {
 				fmt.Fprintf(stderr, "normalize approved Schema command migrations: %v\n", err)
 				return 2
 			}
+		} else if flagMigrationPair {
+			baseline, err = normalizeSchemaFlagMigrations(baseline, current, flagMigrations)
+			if err != nil {
+				fmt.Fprintf(stderr, "normalize approved Schema flag migrations: %v\n", err)
+				return 2
+			}
 		}
 		failures := checkCompatibility(baseline, current)
 		if len(failures) > 0 {
@@ -1367,6 +1394,328 @@ func normalizeSchemaFlagMigrations(
 	return normalized, nil
 }
 
+// normalizeSchemaCommandMigrationLineage composes two independently reviewed
+// migration receipts without inventing a second alias authority. A consumed
+// flag migration may supply the historical predecessor of a command_move
+// parameter, but only after the merge-base Schema or a retained consumed
+// command receipt proves the corresponding next hop.
+func normalizeSchemaCommandMigrationLineage(
+	historical schemaContract,
+	mergeBase schemaContract,
+	current schemaContract,
+	flagMigrations []interfacesnapshot.FlagMigration,
+	commandMigrations []interfacesnapshot.CommandMigration,
+) (schemaContract, error) {
+	normalized, err := normalizeSchemaFlagMigrations(historical, current, flagMigrations)
+	if err != nil {
+		return schemaContract{}, fmt.Errorf("normalize ordinary flag migrations: %w", err)
+	}
+	staged, err := stageSchemaCommandMigrationPredecessors(
+		normalized,
+		mergeBase,
+		current,
+		flagMigrations,
+		commandMigrations,
+	)
+	if err != nil {
+		return schemaContract{}, err
+	}
+	return normalizeSchemaCommandMigrations(staged, current, commandMigrations)
+}
+
+// stageSchemaCommandMigrationPredecessors replays only the name-changing edge
+// recorded by a base-owned consumed flag migration. It leaves interface,
+// safety, dry-run, and positional facts untouched so the ordinary checker
+// remains authoritative for every non-name change.
+func stageSchemaCommandMigrationPredecessors(
+	historical schemaContract,
+	mergeBase schemaContract,
+	current schemaContract,
+	flagMigrations []interfacesnapshot.FlagMigration,
+	commandMigrations []interfacesnapshot.CommandMigration,
+) (schemaContract, error) {
+	staged := cloneContract(historical)
+	moveBySource := map[schemaToolRef]string{}
+	for _, migration := range commandMigrations {
+		if migration.Kind != interfacesnapshot.CommandMigrationMove {
+			continue
+		}
+		ref := schemaToolRef{productID: migration.Schema.ProductID, toolID: migration.Schema.SourceToolID}
+		if previous, exists := moveBySource[ref]; exists {
+			return schemaContract{}, fmt.Errorf(
+				"approved command migrations fork Schema source tool %q between %q and %q",
+				migration.Schema.SourceToolID,
+				previous,
+				migration.Legacy.Command,
+			)
+		}
+		moveBySource[ref] = migration.Legacy.Command
+	}
+
+	for _, migration := range commandMigrations {
+		if migration.Kind != interfacesnapshot.CommandMigrationMove {
+			continue
+		}
+		oldProduct, productExists := historical.Products[migration.Schema.ProductID]
+		oldTool, toolExists := oldProduct.Tools[migration.Schema.SourceToolID]
+		if !productExists || !toolExists {
+			continue
+		}
+		legacyPath := strings.TrimPrefix(migration.Legacy.Command, "dws ")
+		replacementPath := strings.TrimPrefix(migration.Replacement.Command, "dws ")
+		if oldTool.PrimaryCLIPath == replacementPath {
+			continue
+		}
+		if oldTool.PrimaryCLIPath != legacyPath {
+			// Preserve the existing command normalizer's deterministic path error.
+			continue
+		}
+
+		baseProduct, baseProductExists := mergeBase.Products[migration.Schema.ProductID]
+		baseTool, baseToolExists := baseProduct.Tools[migration.Schema.SourceToolID]
+		currentProduct, currentProductExists := current.Products[migration.Schema.ProductID]
+		currentTool, currentToolExists := currentProduct.Tools[migration.Schema.SourceToolID]
+		firstHopRenames := map[string]string{}
+		composedRenames := map[string]string{}
+		lineageApplied := false
+
+		for _, parameter := range migration.Schema.Parameters {
+			if _, direct := oldTool.Parameters[parameter.From]; direct {
+				for _, flagMigration := range flagMigrations {
+					if flagMigration.Command != migration.Legacy.Command ||
+						flagMigration.Canonical.Name != parameter.From {
+						continue
+					}
+					if _, legacyAlsoPublished := oldTool.Parameters[flagMigration.Legacy.Name]; legacyAlsoPublished {
+						return schemaContract{}, fmt.Errorf(
+							"approved command migration %q historical Schema tool publishes both predecessor %q and intermediate %q",
+							migration.Legacy.Command,
+							flagMigration.Legacy.Name,
+							parameter.From,
+						)
+					}
+				}
+				composedRenames[parameter.From] = parameter.To
+				continue
+			}
+
+			predecessors := make([]interfacesnapshot.FlagMigration, 0, 1)
+			for _, flagMigration := range flagMigrations {
+				if flagMigration.Command != migration.Legacy.Command ||
+					flagMigration.Canonical.Name != parameter.From {
+					continue
+				}
+				if flagMigration.State != interfacesnapshot.FlagMigrationConsumed {
+					return schemaContract{}, fmt.Errorf(
+						"approved command migration %q Schema predecessor %q -> %q requires a consumed flag migration receipt",
+						migration.Legacy.Command,
+						flagMigration.Legacy.Name,
+						parameter.From,
+					)
+				}
+				if _, published := oldTool.Parameters[flagMigration.Legacy.Name]; published {
+					predecessors = append(predecessors, flagMigration)
+				}
+			}
+			if len(predecessors) == 0 {
+				continue
+			}
+
+			lineageApplied = true
+			if !baseProductExists || !baseToolExists {
+				return schemaContract{}, fmt.Errorf(
+					"approved command migration %q merge-base Schema lacks source tool %q",
+					migration.Legacy.Command,
+					migration.Schema.SourceToolID,
+				)
+			}
+			var stagedParameter parameterSchema
+			switch migration.State {
+			case interfacesnapshot.CommandMigrationPending:
+				if baseTool.PrimaryCLIPath != legacyPath {
+					return schemaContract{}, fmt.Errorf(
+						"pending command migration %q merge-base Schema source tool has primary_cli_path %q",
+						migration.Legacy.Command,
+						baseTool.PrimaryCLIPath,
+					)
+				}
+				intermediate, exists := baseTool.Parameters[parameter.From]
+				if !exists {
+					return schemaContract{}, fmt.Errorf(
+						"pending command migration %q merge-base Schema lacks intermediate parameter %q",
+						migration.Legacy.Command,
+						parameter.From,
+					)
+				}
+				if _, exists := baseTool.Parameters[parameter.To]; exists {
+					return schemaContract{}, fmt.Errorf(
+						"pending command migration %q merge-base Schema already publishes final parameter %q",
+						migration.Legacy.Command,
+						parameter.To,
+					)
+				}
+				stagedParameter = intermediate
+			case interfacesnapshot.CommandMigrationConsumed:
+				if baseTool.PrimaryCLIPath != replacementPath {
+					return schemaContract{}, fmt.Errorf(
+						"consumed command migration %q merge-base Schema source tool has primary_cli_path %q",
+						migration.Legacy.Command,
+						baseTool.PrimaryCLIPath,
+					)
+				}
+				finalParameter, exists := baseTool.Parameters[parameter.To]
+				if !exists {
+					return schemaContract{}, fmt.Errorf(
+						"consumed command migration %q merge-base Schema lacks final parameter %q",
+						migration.Legacy.Command,
+						parameter.To,
+					)
+				}
+				if _, exists := baseTool.Parameters[parameter.From]; exists {
+					return schemaContract{}, fmt.Errorf(
+						"consumed command migration %q merge-base Schema still publishes intermediate parameter %q",
+						migration.Legacy.Command,
+						parameter.From,
+					)
+				}
+				stagedParameter = oldTool.Parameters[predecessors[0].Legacy.Name]
+				for _, predecessor := range predecessors {
+					oldParameter := oldTool.Parameters[predecessor.Legacy.Name]
+					composite := interfacesnapshot.CommandParameterMigration{From: predecessor.Legacy.Name, To: parameter.To}
+					if err := validateEquivalentCommandSchemaParameter(migration, composite, oldParameter, finalParameter); err != nil {
+						return schemaContract{}, err
+					}
+				}
+			default:
+				return schemaContract{}, fmt.Errorf(
+					"approved command migration %q has unsupported lineage state %q",
+					migration.Legacy.Command,
+					migration.State,
+				)
+			}
+
+			stagedProduct := staged.Products[migration.Schema.ProductID]
+			stagedTool := stagedProduct.Tools[migration.Schema.SourceToolID]
+			for _, predecessor := range predecessors {
+				if predecessor.Legacy.Name == parameter.To {
+					return schemaContract{}, fmt.Errorf(
+						"approved command migration %q forms a Schema parameter lineage cycle through %q",
+						migration.Legacy.Command,
+						parameter.To,
+					)
+				}
+				if existing, claimed := firstHopRenames[predecessor.Legacy.Name]; claimed && existing != parameter.From {
+					return schemaContract{}, fmt.Errorf(
+						"approved command migration %q forks Schema predecessor %q to both %q and %q",
+						migration.Legacy.Command,
+						predecessor.Legacy.Name,
+						existing,
+						parameter.From,
+					)
+				}
+				oldParameter := oldTool.Parameters[predecessor.Legacy.Name]
+				if migration.State == interfacesnapshot.CommandMigrationPending {
+					if err := validateRenamedSchemaParameter(predecessor, oldParameter, stagedParameter); err != nil {
+						return schemaContract{}, err
+					}
+				}
+				if _, exists := baseTool.Parameters[predecessor.Legacy.Name]; exists {
+					return schemaContract{}, fmt.Errorf(
+						"approved command migration %q merge-base Schema still publishes predecessor parameter %q",
+						migration.Legacy.Command,
+						predecessor.Legacy.Name,
+					)
+				}
+				if currentProductExists && currentToolExists {
+					if _, exists := currentTool.Parameters[predecessor.Legacy.Name]; exists {
+						return schemaContract{}, fmt.Errorf(
+							"approved command migration %q current Schema still publishes predecessor parameter %q",
+							migration.Legacy.Command,
+							predecessor.Legacy.Name,
+						)
+					}
+				}
+				delete(stagedTool.Parameters, predecessor.Legacy.Name)
+				firstHopRenames[predecessor.Legacy.Name] = parameter.From
+				composedRenames[predecessor.Legacy.Name] = parameter.To
+			}
+			stagedTool.Parameters[parameter.From] = stagedParameter
+			stagedProduct.Tools[migration.Schema.SourceToolID] = stagedTool
+			staged.Products[migration.Schema.ProductID] = stagedProduct
+		}
+
+		if !lineageApplied {
+			continue
+		}
+		matches := schemaToolsByPrimaryPath(historical, legacyPath)
+		wantRef := schemaToolRef{productID: migration.Schema.ProductID, toolID: migration.Schema.SourceToolID}
+		if len(matches) != 1 || matches[0] != wantRef {
+			return schemaContract{}, fmt.Errorf(
+				"approved command migration %q predecessor lineage requires one exact historical Schema tool, got %#v",
+				migration.Legacy.Command,
+				matches,
+			)
+		}
+		if currentProductExists && currentToolExists {
+			if source, found := migratedConstraintSourceParameter(currentTool.Constraints, firstHopRenames); found {
+				return schemaContract{}, fmt.Errorf(
+					"approved command migration %q current Schema constraints still reference predecessor parameter %q",
+					migration.Legacy.Command,
+					source,
+				)
+			}
+		}
+		for _, finalTarget := range composedRenames {
+			if _, cycle := firstHopRenames[finalTarget]; cycle {
+				return schemaContract{}, fmt.Errorf(
+					"approved command migration %q forms a Schema parameter lineage cycle through %q",
+					migration.Legacy.Command,
+					finalTarget,
+				)
+			}
+		}
+
+		firstHopConstraints, firstHopOK := canonicalizeMigratedConstraints(oldTool.Constraints, firstHopRenames)
+		if !firstHopOK {
+			return schemaContract{}, fmt.Errorf(
+				"approved command migration %q historical Schema constraints are not canonicalizable",
+				migration.Legacy.Command,
+			)
+		}
+		baseConstraints, baseOK := canonicalizeMigratedConstraints(baseTool.Constraints, nil)
+		if !baseOK {
+			return schemaContract{}, fmt.Errorf(
+				"approved command migration %q merge-base Schema constraints are not canonicalizable",
+				migration.Legacy.Command,
+			)
+		}
+		stagedProduct := staged.Products[migration.Schema.ProductID]
+		stagedTool := stagedProduct.Tools[migration.Schema.SourceToolID]
+		switch migration.State {
+		case interfacesnapshot.CommandMigrationPending:
+			if firstHopConstraints != baseConstraints {
+				return schemaContract{}, fmt.Errorf(
+					"pending command migration %q predecessor lineage changed merge-base Schema constraints",
+					migration.Legacy.Command,
+				)
+			}
+			stagedTool.Constraints = baseTool.Constraints
+		case interfacesnapshot.CommandMigrationConsumed:
+			composedConstraints, composedOK := canonicalizeMigratedConstraints(oldTool.Constraints, composedRenames)
+			if !composedOK || composedConstraints != baseConstraints {
+				return schemaContract{}, fmt.Errorf(
+					"consumed command migration %q predecessor lineage changed merge-base Schema constraints",
+					migration.Legacy.Command,
+				)
+			}
+			stagedTool.Constraints = firstHopConstraints
+		}
+		stagedProduct.Tools[migration.Schema.SourceToolID] = stagedTool
+		staged.Products[migration.Schema.ProductID] = stagedProduct
+	}
+	return staged, nil
+}
+
 // normalizeSchemaCommandMigrations projects only the Schema consequences that
 // are coupled to an already-authorized CLI command migration. It rewrites a
 // cloned historical contract; the ordinary checker still rejects every field
@@ -1478,12 +1827,30 @@ func normalizeSchemaCommandMigrations(
 					)
 				}
 			}
-			if oldTool.Constraints != newSource.Constraints {
-				oldConstraints, oldOK := canonicalizeMigratedConstraints(oldTool.Constraints, renames)
-				newConstraints, newOK := canonicalizeMigratedConstraints(newSource.Constraints, nil)
-				if oldOK && newOK && oldConstraints == newConstraints {
-					normalizedTool.Constraints = newSource.Constraints
-				}
+			oldConstraints, oldOK := canonicalizeMigratedConstraints(oldTool.Constraints, renames)
+			if !oldOK {
+				return schemaContract{}, fmt.Errorf(
+					"approved command migration %q historical Schema constraints are not canonicalizable",
+					migration.Legacy.Command,
+				)
+			}
+			newConstraints, newOK := canonicalizeMigratedConstraints(newSource.Constraints, nil)
+			if !newOK {
+				return schemaContract{}, fmt.Errorf(
+					"approved command migration %q current Schema constraints are not canonicalizable",
+					migration.Legacy.Command,
+				)
+			}
+			if source, found := migratedConstraintSourceParameter(newSource.Constraints, renames); found {
+				return schemaContract{}, fmt.Errorf(
+					"approved command migration %q current constraints still reference legacy Schema constraint parameter %q",
+					migration.Legacy.Command,
+					source,
+				)
+			}
+			normalizedTool.Constraints = oldConstraints
+			if oldConstraints == newConstraints {
+				normalizedTool.Constraints = newSource.Constraints
 			}
 			normalizedTool.PrimaryCLIPath = replacementPath
 
@@ -1938,6 +2305,23 @@ func canonicalizeMigratedConstraints(raw string, renames map[string]string) (str
 	return string(encoded), err == nil
 }
 
+func migratedConstraintSourceParameter(raw string, renames map[string]string) (string, bool) {
+	groups, ok := parseMigrationConstraintsStrict(raw)
+	if !ok {
+		return "", false
+	}
+	for _, kind := range []string{"mutually_exclusive", "require_one_of", "require_together"} {
+		for _, group := range groups[kind] {
+			for _, member := range group {
+				if _, renamed := renames[member]; renamed {
+					return member, true
+				}
+			}
+		}
+	}
+	return "", false
+}
+
 func parseMigrationConstraintsStrict(raw string) (map[string][][]string, bool) {
 	trimmed := strings.TrimSpace(raw)
 	if trimmed == "" {
diff --git a/scripts/policy/schemacompat/authority_integration_test.go b/scripts/policy/schemacompat/authority_integration_test.go
index be8857f4..9346e1c1 100644
--- a/scripts/policy/schemacompat/authority_integration_test.go
+++ b/scripts/policy/schemacompat/authority_integration_test.go
@@ -173,8 +173,9 @@ func main() {
 	currentSnapshot := flag.String("migration-current-snapshot", "", "candidate interface snapshot")
 	baseSnapshot := flag.String("migration-base-snapshot", "", "base interface snapshot")
 	stableSnapshot := flag.String("migration-stable-snapshot", "", "stable interface snapshot")
-	_ = flag.String("approved-command-migrations", "", "base command ledger")
-	_ = flag.String("candidate-command-migrations", "", "candidate command ledger")
+	migrationBaseSchema := flag.String("migration-base-schema", "", "merge-base Schema contract")
+	approvedCommand := flag.String("approved-command-migrations", "", "base command ledger")
+	candidateCommand := flag.String("candidate-command-migrations", "", "candidate command ledger")
 	flag.Parse()
 
 	if *normalize != "" {
@@ -214,6 +215,29 @@ func main() {
 			os.Exit(2)
 		}
 	}
+	commandPair := *approvedCommand != "" || *candidateCommand != ""
+	if commandPair && (*approvedCommand == "" || *candidateCommand == "") {
+		fmt.Fprintln(os.Stderr, "stable Schema guard received a partial command migration pair")
+		os.Exit(2)
+	}
+	if commandPair {
+		data, err := os.ReadFile(*migrationBaseSchema)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(2)
+		}
+		if !strings.Contains(string(data), "BASE_AUTHORITY") {
+			fmt.Fprintf(os.Stderr, "migration base Schema is not base-owned: %s\n", data)
+			os.Exit(2)
+		}
+		fmt.Fprintln(os.Stdout, "BASE_SCHEMA_LINEAGE=BASE_AUTHORITY")
+	} else {
+		if *migrationBaseSchema != "" {
+			fmt.Fprintln(os.Stderr, "flag-only Schema check received command migration lineage")
+			os.Exit(2)
+		}
+		fmt.Fprintln(os.Stdout, "FLAG_ONLY_SCHEMA_LINEAGE_OMITTED")
+	}
 	currentData, err := os.ReadFile(*current)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, err)
@@ -418,9 +442,16 @@ func TestCrossPlatformCoverageSchemaCompatibilityUsesBaseOwnedAuthority(t *testi
 			authorityMarker: "BASE_SCHEMA_CHECKER_ENFORCED",
 		},
 		{
-			name:            "governed checker protects stable Schema contract",
+			name:              "governed checker protects stable Schema contract",
+			baseGovernance:    "complete",
+			commandGovernance: "complete",
+			checkerMode:       "stable-schema-guard",
+			authorityMarker:   "STABLE_SCHEMA_CONTRACT_ENFORCED",
+		},
+		{
+			name:            "lineage capable checker omits command lineage for flag-only governance",
 			baseGovernance:  "complete",
-			checkerMode:     "stable-schema-guard",
+			checkerMode:     "flag-only-schema-guard",
 			authorityMarker: "STABLE_SCHEMA_CONTRACT_ENFORCED",
 		},
 		{
@@ -611,7 +642,7 @@ func runSchemaAuthorityCase(t *testing.T, test authorityScenario) {
 	switch test.baseGovernance {
 	case "complete":
 		checkerSource := governedSchemaCheckerSource
-		if test.checkerMode == "stable-schema-guard" {
+		if test.checkerMode == "stable-schema-guard" || test.checkerMode == "flag-only-schema-guard" {
 			checkerSource = stableSchemaGuardCheckerSource
 		}
 		schemaWriteFile(t, filepath.Join(fixtureRoot, "scripts", "policy", "schema-compat", "main.go"), checkerSource, 0o644)
@@ -794,6 +825,12 @@ func runSchemaAuthorityCase(t *testing.T, test authorityScenario) {
 		if test.baseGovernance == "complete" && strings.Count(got, "BASE_INTERFACE_HELPER_GENERATE=BASE") != 3 {
 			t.Fatalf("governed Schema check did not generate three base-owned interface snapshots; output:\n%s", got)
 		}
+		if test.checkerMode == "stable-schema-guard" && strings.Count(got, "BASE_SCHEMA_LINEAGE=BASE_AUTHORITY") != 2 {
+			t.Fatalf("governed Schema check did not pass the base-owned Schema lineage to both historical checks; output:\n%s", got)
+		}
+		if test.checkerMode == "flag-only-schema-guard" && strings.Count(got, "FLAG_ONLY_SCHEMA_LINEAGE_OMITTED") != 2 {
+			t.Fatalf("flag-only Schema check received command migration lineage; output:\n%s", got)
+		}
 
 		wrongStable := exec.Command(
 			"sh",
diff --git a/scripts/release/check-release-compatibility.sh b/scripts/release/check-release-compatibility.sh
new file mode 100755
index 00000000..290826bb
--- /dev/null
+++ b/scripts/release/check-release-compatibility.sh
@@ -0,0 +1,122 @@
+#!/bin/sh
+set -eu
+
+# Release compatibility is one decision seam over the sealed source tree.
+# Trusted release tooling may orchestrate this script, but the explicitly
+# selected repository remains the authority for both CLI and Schema checks.
+
+REPO_ROOT=""
+BASE_REF=""
+STABLE_REF=""
+CANDIDATE_REF="HEAD"
+
+usage() {
+  printf '%s\n' \
+    "usage: $0 --repo-root <path> --base-ref <ref> --stable-ref <ref> [--candidate-ref <ref>]" >&2
+}
+
+while [ "$#" -gt 0 ]; do
+  case "$1" in
+    --repo-root)
+      [ "$#" -ge 2 ] || { usage; exit 2; }
+      REPO_ROOT="$2"
+      shift 2
+      ;;
+    --base-ref)
+      [ "$#" -ge 2 ] || { usage; exit 2; }
+      BASE_REF="$2"
+      shift 2
+      ;;
+    --stable-ref)
+      [ "$#" -ge 2 ] || { usage; exit 2; }
+      STABLE_REF="$2"
+      shift 2
+      ;;
+    --candidate-ref)
+      [ "$#" -ge 2 ] || { usage; exit 2; }
+      CANDIDATE_REF="$2"
+      shift 2
+      ;;
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    *)
+      printf 'error: unknown argument: %s\n' "$1" >&2
+      usage
+      exit 2
+      ;;
+  esac
+done
+
+[ -n "$REPO_ROOT" ] && [ -n "$BASE_REF" ] && [ -n "$STABLE_REF" ] || {
+  usage
+  exit 2
+}
+
+REPO_ROOT="$(CDPATH= cd -- "$REPO_ROOT" && pwd -P)" || {
+  printf 'error: release source root is not available: %s\n' "$REPO_ROOT" >&2
+  exit 2
+}
+GIT_ROOT="$(git -C "$REPO_ROOT" rev-parse --show-toplevel 2>/dev/null)" || {
+  printf 'error: release source root is not a Git worktree: %s\n' "$REPO_ROOT" >&2
+  exit 2
+}
+[ "$GIT_ROOT" = "$REPO_ROOT" ] || {
+  printf 'error: release source root must be the Git worktree root: %s\n' "$REPO_ROOT" >&2
+  exit 2
+}
+
+CLI_CHECK="$REPO_ROOT/scripts/policy/check-authoritative-interface-baselines.sh"
+SCHEMA_CHECK="$REPO_ROOT/scripts/policy/check-authoritative-schema-compatibility.sh"
+for check in "$CLI_CHECK" "$SCHEMA_CHECK"; do
+  [ -x "$check" ] || {
+    printf 'error: authoritative release compatibility checker is unavailable: %s\n' "$check" >&2
+    exit 2
+  }
+done
+
+resolve_commit() {
+  label="$1"
+  ref="$2"
+  commit="$(git -C "$REPO_ROOT" rev-parse --verify "${ref}^{commit}" 2>/dev/null)" || {
+    printf 'error: release %s ref is not available in sealed source: %s\n' "$label" "$ref" >&2
+    return 2
+  }
+  [ -n "$commit" ] || {
+    printf 'error: release %s ref resolved to an empty commit: %s\n' "$label" "$ref" >&2
+    return 2
+  }
+  printf '%s\n' "$commit"
+}
+
+# Freeze the complete comparison tuple before either checker runs. Otherwise a
+# concurrent ref update (or the first checker itself) could make Schema inspect
+# different Git objects from the CLI gate even when both receive the same names.
+BASE_COMMIT="$(resolve_commit base "$BASE_REF")"
+STABLE_COMMIT="$(resolve_commit stable "$STABLE_REF")"
+CANDIDATE_COMMIT="$(resolve_commit candidate "$CANDIDATE_REF")"
+
+printf '==> Checking authoritative CLI compatibility\n'
+if "$CLI_CHECK" \
+    --base-ref "$BASE_COMMIT" \
+    --stable-ref "$STABLE_COMMIT" \
+    --candidate-ref "$CANDIDATE_COMMIT"; then
+  :
+else
+  status=$?
+  printf 'error: authoritative CLI compatibility failed\n' >&2
+  exit "$status"
+fi
+
+printf '==> Checking authoritative Schema compatibility\n'
+if "$SCHEMA_CHECK" \
+    --base-ref "$BASE_COMMIT" \
+    --stable-ref "$STABLE_COMMIT" \
+    --candidate-ref "$CANDIDATE_COMMIT"; then
+  :
+else
+  status=$?
+  printf 'error: authoritative Schema compatibility failed\n' >&2
+  exit "$status"
+fi
diff --git a/scripts/release/release.sh b/scripts/release/release.sh
index bb7dea1f..eb44b5a5 100755
--- a/scripts/release/release.sh
+++ b/scripts/release/release.sh
@@ -19,7 +19,7 @@ usage() {
   cat >&2 <<'EOF'
 usage: release.sh <prerelease|stable> <version> [options]
 
-Runs the full test, command-compatibility, package, and install preflight.
+Runs the full test, authoritative CLI/Schema compatibility, package, and install preflight.
 The default is validation only. Official publication is cloud-only.
 
 Options:
@@ -359,10 +359,12 @@ else
   make policy
 
   if [ -n "$previous_stable" ]; then
-    printf '==> Comparing command tree with %s\n' "$previous_stable"
-    "$ROOT/scripts/policy/check-command-compatibility.sh" \
+    printf '==> Comparing authoritative CLI and Schema with %s\n' "$previous_stable"
+    "$SCRIPT_DIR/check-release-compatibility.sh" \
+      --repo-root "$ROOT" \
       --base-ref HEAD \
-      --stable-ref "$previous_stable"
+      --stable-ref "$previous_stable" \
+      --candidate-ref HEAD
   fi
 
   printf '==> Building local release artifacts for %s\n' "$VERSION"
@@ -412,11 +414,13 @@ printf '==> Revalidating delivered stable baseline %s\n' "$previous_stable"
 require_delivered_previous_stable
 
 if [ "$previous_stable" != "$previous_stable_before_refresh" ]; then
-  printf '==> Stable authority advanced from %s to %s; rechecking command compatibility\n' \
+  printf '==> Stable authority advanced from %s to %s; rechecking authoritative CLI and Schema compatibility\n' \
     "${previous_stable_before_refresh:-none}" "$previous_stable"
-  "$ROOT/scripts/policy/check-command-compatibility.sh" \
+  "$SCRIPT_DIR/check-release-compatibility.sh" \
+    --repo-root "$ROOT" \
     --base-ref HEAD \
-    --stable-ref "$previous_stable"
+    --stable-ref "$previous_stable" \
+    --candidate-ref HEAD
 fi
 
 if [ "$PUBLISH" -eq 1 ]; then
diff --git a/test/scripts/package_script_test.go b/test/scripts/package_script_test.go
index 46155da0..73798dcd 100644
--- a/test/scripts/package_script_test.go
+++ b/test/scripts/package_script_test.go
@@ -1303,13 +1303,25 @@ func TestReleaseWorkflowParallelizesSealedValidationWithoutWeakeningPublication(
 		"- e2e",
 		"verify-github-tag-authority.sh",
 		"go test -v -count=1 -timeout=5m ./test/scripts/... -run '^TestRelease'",
-		"check-command-compatibility.sh",
+		`tmp/trusted-release-tooling/scripts/release/check-release-compatibility.sh`,
+		`--repo-root "$GITHUB_WORKSPACE"`,
+		`--base-ref HEAD`,
+		`--stable-ref "$PREVIOUS_STABLE"`,
+		`--candidate-ref HEAD`,
 		"test-multi-profile-e2e.sh",
 	} {
 		if !strings.Contains(validation, required) {
 			t.Errorf("parallel release validation is missing %q", required)
 		}
 	}
+	for _, forbidden := range []string{
+		"./scripts/policy/check-command-compatibility.sh",
+		"./scripts/policy/check-authoritative-schema-compatibility.sh",
+	} {
+		if strings.Contains(validation, forbidden) {
+			t.Errorf("parallel release validation bypasses the shared compatibility runner with %q", forbidden)
+		}
+	}
 
 	if strings.Contains(build, "test-multi-profile-e2e.sh") {
 		t.Error("multi-profile E2E must not serialize GoReleaser")
@@ -1379,7 +1391,7 @@ func TestReleaseWorkflowHidesOnlyVerifiedSealedTagFromCompatibilityBaseline(t *t
 
 	verifiedTag := strings.Index(validation, "verify-github-tag-authority.sh")
 	deleteLocalTag := strings.Index(validation, "git update-ref -d")
-	compatibility := strings.Index(validation, "check-command-compatibility.sh")
+	compatibility := strings.Index(validation, "tmp/trusted-release-tooling/scripts/release/check-release-compatibility.sh")
 	if verifiedTag == -1 || deleteLocalTag == -1 || compatibility == -1 ||
 		verifiedTag > deleteLocalTag || deleteLocalTag > compatibility {
 		t.Fatal("release tag authority verification, local candidate removal, and compatibility checking must stay ordered")
diff --git a/test/scripts/release_script_test.go b/test/scripts/release_script_test.go
index 6ad03b77..7c8e98cc 100644
--- a/test/scripts/release_script_test.go
+++ b/test/scripts/release_script_test.go
@@ -75,6 +75,7 @@ type releaseTestRepo struct {
 	prepare    string
 	render     string
 	releaseCmd string
+	compat     string
 	lib        string
 	verify     string
 }
@@ -110,11 +111,206 @@ func newReleaseTestRepo(t *testing.T) *releaseTestRepo {
 		prepare:    filepath.Join(sourceRoot, "scripts", "release", "prepare-changelog.sh"),
 		render:     filepath.Join(sourceRoot, "scripts", "release", "render-release-fragments.sh"),
 		releaseCmd: filepath.Join(sourceRoot, "scripts", "release", "release.sh"),
+		compat:     filepath.Join(sourceRoot, "scripts", "release", "check-release-compatibility.sh"),
 		lib:        filepath.Join(sourceRoot, "scripts", "release", "release-lib.sh"),
 		verify:     filepath.Join(sourceRoot, "scripts", "release", "verify-release-artifacts.sh"),
 	}
 }
 
+func seedReleaseCompatibilityRefs(t *testing.T, repo string) (stable, base, candidate string) {
+	t.Helper()
+	mustRun(t, repo, "git", "config", "user.name", "Release Compatibility Test")
+	mustRun(t, repo, "git", "config", "user.email", "release-compatibility-test@example.com")
+	mustWriteFile(t, filepath.Join(repo, "seed.txt"), []byte("stable\n"), 0o644)
+	mustRun(t, repo, "git", "add", "seed.txt")
+	mustRun(t, repo, "git", "commit", "-m", "stable")
+	mustRun(t, repo, "git", "tag", "stable-ref")
+	stable = strings.TrimSpace(mustOutput(t, repo, "git", "rev-parse", "HEAD^{commit}"))
+
+	mustWriteFile(t, filepath.Join(repo, "seed.txt"), []byte("base\n"), 0o644)
+	mustRun(t, repo, "git", "add", "seed.txt")
+	mustRun(t, repo, "git", "commit", "-m", "base")
+	mustRun(t, repo, "git", "branch", "base-ref")
+	base = strings.TrimSpace(mustOutput(t, repo, "git", "rev-parse", "HEAD^{commit}"))
+
+	mustWriteFile(t, filepath.Join(repo, "seed.txt"), []byte("candidate\n"), 0o644)
+	mustRun(t, repo, "git", "add", "seed.txt")
+	mustRun(t, repo, "git", "commit", "-m", "candidate")
+	mustRun(t, repo, "git", "branch", "candidate-ref")
+	candidate = strings.TrimSpace(mustOutput(t, repo, "git", "rev-parse", "HEAD^{commit}"))
+	return stable, base, candidate
+}
+
+func TestReleaseCompatibilityCheckRunsCLIAndSchemaWithExactRefs(t *testing.T) {
+	t.Parallel()
+	sourceRoot, err := filepath.Abs(filepath.Join("..", ".."))
+	if err != nil {
+		t.Fatalf("Abs(repo root) error = %v", err)
+	}
+	runner := filepath.Join(sourceRoot, "scripts", "release", "check-release-compatibility.sh")
+	repo := t.TempDir()
+	mustRun(t, repo, "git", "init", "-b", "main")
+	stable, base, candidate := seedReleaseCompatibilityRefs(t, repo)
+
+	trace := filepath.Join(t.TempDir(), "compatibility.log")
+	checker := func(name string) []byte {
+		return []byte("#!/bin/sh\nset -eu\nprintf '" + name + ":%s\\n' \"$*\" >> \"$TRACE\"\n")
+	}
+	mustWriteFile(t, filepath.Join(repo, "scripts", "policy", "check-authoritative-interface-baselines.sh"), checker("cli"), 0o755)
+	mustWriteFile(t, filepath.Join(repo, "scripts", "policy", "check-authoritative-schema-compatibility.sh"), checker("schema"), 0o755)
+
+	cmd := exec.Command(
+		runner,
+		"--repo-root", repo,
+		"--base-ref", "base-ref",
+		"--stable-ref", "stable-ref",
+		"--candidate-ref", "candidate-ref",
+	)
+	cmd.Env = append(os.Environ(), "TRACE="+trace)
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("release compatibility check error = %v\noutput:\n%s", err, output)
+	}
+	got, err := os.ReadFile(trace)
+	if err != nil {
+		t.Fatalf("ReadFile(%s) error = %v", trace, err)
+	}
+	want := fmt.Sprintf("cli:--base-ref %s --stable-ref %s --candidate-ref %s\n", base, stable, candidate) +
+		fmt.Sprintf("schema:--base-ref %s --stable-ref %s --candidate-ref %s\n", base, stable, candidate)
+	if string(got) != want {
+		t.Fatalf("release compatibility calls = %q, want %q", got, want)
+	}
+}
+
+func TestReleaseCompatibilityCheckFreezesRefsBeforeRunningEitherChecker(t *testing.T) {
+	t.Parallel()
+	sourceRoot, err := filepath.Abs(filepath.Join("..", ".."))
+	if err != nil {
+		t.Fatalf("Abs(repo root) error = %v", err)
+	}
+	runner := filepath.Join(sourceRoot, "scripts", "release", "check-release-compatibility.sh")
+	repo := t.TempDir()
+	mustRun(t, repo, "git", "init", "-b", "main")
+	stable, base, candidate := seedReleaseCompatibilityRefs(t, repo)
+
+	trace := filepath.Join(t.TempDir(), "compatibility.log")
+	resolveAndLog := `
+base="$2"
+stable="$4"
+candidate="$6"
+printf '%s:%s:%s:%s\n' "$CHECK_NAME" \
+  "$(git -C "$REPO_ROOT_FOR_TEST" rev-parse --verify "${base}^{commit}")" \
+  "$(git -C "$REPO_ROOT_FOR_TEST" rev-parse --verify "${stable}^{commit}")" \
+  "$(git -C "$REPO_ROOT_FOR_TEST" rev-parse --verify "${candidate}^{commit}")" >> "$TRACE"
+`
+	mustWriteFile(t, filepath.Join(repo, "scripts", "policy", "check-authoritative-interface-baselines.sh"), []byte("#!/bin/sh\nset -eu\nCHECK_NAME=cli\n"+resolveAndLog+"git -C \"$REPO_ROOT_FOR_TEST\" update-ref refs/heads/base-ref \"$MUTATE_TO\"\n"), 0o755)
+	mustWriteFile(t, filepath.Join(repo, "scripts", "policy", "check-authoritative-schema-compatibility.sh"), []byte("#!/bin/sh\nset -eu\nCHECK_NAME=schema\n"+resolveAndLog), 0o755)
+
+	cmd := exec.Command(
+		runner,
+		"--repo-root", repo,
+		"--base-ref", "base-ref",
+		"--stable-ref", "stable-ref",
+		"--candidate-ref", "candidate-ref",
+	)
+	cmd.Env = append(os.Environ(), "TRACE="+trace, "REPO_ROOT_FOR_TEST="+repo, "MUTATE_TO="+candidate)
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("release compatibility check error = %v\noutput:\n%s", err, output)
+	}
+	got, err := os.ReadFile(trace)
+	if err != nil {
+		t.Fatalf("ReadFile(%s) error = %v", trace, err)
+	}
+	want := fmt.Sprintf("cli:%s:%s:%s\nschema:%s:%s:%s\n", base, stable, candidate, base, stable, candidate)
+	if string(got) != want {
+		t.Fatalf("release compatibility resolved commits = %q, want %q", got, want)
+	}
+	if moved := strings.TrimSpace(mustOutput(t, repo, "git", "rev-parse", "base-ref^{commit}")); moved != candidate {
+		t.Fatalf("mutating checker did not move base-ref: got %s, want %s", moved, candidate)
+	}
+}
+
+func TestReleaseCompatibilityCheckStopsBeforeSchemaWhenCLIFails(t *testing.T) {
+	t.Parallel()
+	sourceRoot, err := filepath.Abs(filepath.Join("..", ".."))
+	if err != nil {
+		t.Fatalf("Abs(repo root) error = %v", err)
+	}
+	runner := filepath.Join(sourceRoot, "scripts", "release", "check-release-compatibility.sh")
+	repo := t.TempDir()
+	mustRun(t, repo, "git", "init", "-b", "main")
+	seedReleaseCompatibilityRefs(t, repo)
+
+	trace := filepath.Join(t.TempDir(), "compatibility.log")
+	mustWriteFile(t, filepath.Join(repo, "scripts", "policy", "check-authoritative-interface-baselines.sh"), []byte("#!/bin/sh\nprintf 'cli\\n' >> \"$TRACE\"\nexit 17\n"), 0o755)
+	mustWriteFile(t, filepath.Join(repo, "scripts", "policy", "check-authoritative-schema-compatibility.sh"), []byte("#!/bin/sh\nprintf 'schema\\n' >> \"$TRACE\"\n"), 0o755)
+
+	cmd := exec.Command(
+		runner,
+		"--repo-root", repo,
+		"--base-ref", "base-ref",
+		"--stable-ref", "stable-ref",
+		"--candidate-ref", "candidate-ref",
+	)
+	cmd.Env = append(os.Environ(), "TRACE="+trace)
+	output, err := cmd.CombinedOutput()
+	exitErr, ok := err.(*exec.ExitError)
+	if !ok || exitErr.ExitCode() != 17 {
+		t.Fatalf("release compatibility CLI failure = %v, want exit 17\noutput:\n%s", err, output)
+	}
+	if !strings.Contains(string(output), "error: authoritative CLI compatibility failed") {
+		t.Fatalf("release compatibility CLI failure has no boundary message:\n%s", output)
+	}
+	got, err := os.ReadFile(trace)
+	if err != nil {
+		t.Fatalf("ReadFile(%s) error = %v", trace, err)
+	}
+	if string(got) != "cli\n" {
+		t.Fatalf("checks after CLI failure = %q, want only CLI", got)
+	}
+}
+
+func TestReleaseCompatibilityCheckFailsWhenSchemaFails(t *testing.T) {
+	t.Parallel()
+	sourceRoot, err := filepath.Abs(filepath.Join("..", ".."))
+	if err != nil {
+		t.Fatalf("Abs(repo root) error = %v", err)
+	}
+	runner := filepath.Join(sourceRoot, "scripts", "release", "check-release-compatibility.sh")
+	repo := t.TempDir()
+	mustRun(t, repo, "git", "init", "-b", "main")
+	seedReleaseCompatibilityRefs(t, repo)
+
+	trace := filepath.Join(t.TempDir(), "compatibility.log")
+	mustWriteFile(t, filepath.Join(repo, "scripts", "policy", "check-authoritative-interface-baselines.sh"), []byte("#!/bin/sh\nprintf 'cli\\n' >> \"$TRACE\"\n"), 0o755)
+	mustWriteFile(t, filepath.Join(repo, "scripts", "policy", "check-authoritative-schema-compatibility.sh"), []byte("#!/bin/sh\nprintf 'schema\\n' >> \"$TRACE\"\nexit 19\n"), 0o755)
+
+	cmd := exec.Command(
+		runner,
+		"--repo-root", repo,
+		"--base-ref", "base-ref",
+		"--stable-ref", "stable-ref",
+		"--candidate-ref", "candidate-ref",
+	)
+	cmd.Env = append(os.Environ(), "TRACE="+trace)
+	output, err := cmd.CombinedOutput()
+	exitErr, ok := err.(*exec.ExitError)
+	if !ok || exitErr.ExitCode() != 19 {
+		t.Fatalf("release compatibility Schema failure = %v, want exit 19\noutput:\n%s", err, output)
+	}
+	if !strings.Contains(string(output), "error: authoritative Schema compatibility failed") {
+		t.Fatalf("release compatibility Schema failure has no boundary message:\n%s", output)
+	}
+	got, err := os.ReadFile(trace)
+	if err != nil {
+		t.Fatalf("ReadFile(%s) error = %v", trace, err)
+	}
+	if string(got) != "cli\nschema\n" {
+		t.Fatalf("checks before Schema failure = %q, want CLI then Schema", got)
+	}
+}
+
 func TestReleaseVersionOrdering(t *testing.T) {
 	sourceRoot, err := filepath.Abs(filepath.Join("..", ".."))
 	if err != nil {
@@ -2631,12 +2827,35 @@ func TestReleaseCommandRejectsDifferentFetchAndPushRepositories(t *testing.T) {
 	}
 }
 
+func TestReleaseCommandRunsCLIAndSchemaCompatibilityInInitialPreflight(t *testing.T) {
+	r := newReleaseTestRepo(t)
+	installReleaseCommandFixture(t, r)
+	mustWriteFile(t, filepath.Join(r.root, "CHANGELOG.md"), []byte(releaseChangelog(betaSection())), 0o644)
+	r.commitAndPush(t, "install release compatibility fixture")
+
+	output, err := runReleaseScript(t, r.root, filepath.Join(r.root, "scripts", "release", "release.sh"),
+		"prerelease", "v1.0.1-beta.1", "--remote", "origin",
+	)
+	if err != nil {
+		t.Fatalf("release validation error = %v\noutput:\n%s", err, output)
+	}
+	head := strings.TrimSpace(mustOutput(t, r.root, "git", "rev-parse", "HEAD^{commit}"))
+	stable := strings.TrimSpace(mustOutput(t, r.root, "git", "rev-parse", "v1.0.0^{commit}"))
+	for _, want := range []string{
+		fmt.Sprintf("cli-compatibility --base-ref %s --stable-ref %s --candidate-ref %s", head, stable, head),
+		fmt.Sprintf("schema-compatibility --base-ref %s --stable-ref %s --candidate-ref %s", head, stable, head),
+	} {
+		if !strings.Contains(output, want) {
+			t.Errorf("initial release preflight is missing %q\noutput:\n%s", want, output)
+		}
+	}
+}
+
 func TestReleaseCommandRechecksAdvancedStableAuthority(t *testing.T) {
 	r := newReleaseTestRepo(t)
 	installReleaseCommandFixture(t, r)
 	section := "## [1.0.2-beta.1] - 2026-07-11\n\n### Changed\n\n- Validate a candidate after stable authority advances.\n\n"
 	mustWriteFile(t, filepath.Join(r.root, "CHANGELOG.md"), []byte(releaseChangelog(section)), 0o644)
-	mustWriteFile(t, filepath.Join(r.root, "scripts", "policy", "check-command-compatibility.sh"), []byte("#!/bin/sh\nset -eu\nprintf 'compatibility %s\\n' \"$*\"\n"), 0o755)
 	mustWriteFile(t, filepath.Join(r.root, "Makefile"), []byte("test:\n\t@:\nbuild:\n\t@:\npolicy:\n\t@:\npackage:\n\t@git tag -a v1.0.1 -m 'Release v1.0.1'\n\t@git push origin refs/tags/v1.0.1\n"), 0o644)
 	r.commitAndPush(t, "install advancing release fixture")
 
@@ -2646,20 +2865,28 @@ func TestReleaseCommandRechecksAdvancedStableAuthority(t *testing.T) {
 	if err != nil {
 		t.Fatalf("release validation error = %v\noutput:\n%s", err, output)
 	}
-	if !strings.Contains(output, "Stable authority advanced from v1.0.0 to v1.0.1") ||
-		!strings.Contains(output, "--stable-ref v1.0.1") {
-		t.Fatalf("advanced stable command tree was not rechecked:\n%s", output)
+	head := strings.TrimSpace(mustOutput(t, r.root, "git", "rev-parse", "HEAD^{commit}"))
+	stable := strings.TrimSpace(mustOutput(t, r.root, "git", "rev-parse", "v1.0.1^{commit}"))
+	for _, want := range []string{
+		"Stable authority advanced from v1.0.0 to v1.0.1",
+		fmt.Sprintf("cli-compatibility --base-ref %s --stable-ref %s --candidate-ref %s", head, stable, head),
+		fmt.Sprintf("schema-compatibility --base-ref %s --stable-ref %s --candidate-ref %s", head, stable, head),
+	} {
+		if !strings.Contains(output, want) {
+			t.Errorf("advanced stable authority recheck is missing %q\noutput:\n%s", want, output)
+		}
 	}
 }
 
 func installReleaseCommandFixture(t *testing.T, r *releaseTestRepo) {
 	t.Helper()
-	for _, source := range []string{r.lib, r.contract, r.releaseCmd} {
+	for _, source := range []string{r.lib, r.contract, r.releaseCmd, r.compat} {
 		releaseCopyFile(t, source, filepath.Join(r.root, "scripts", "release", filepath.Base(source)), 0o755)
 	}
 	mustWriteFile(t, filepath.Join(r.root, "scripts", "release", "verify-package-managers.sh"), []byte("#!/bin/sh\nset -eu\nexit 0\n"), 0o755)
 	mustWriteFile(t, filepath.Join(r.root, "scripts", "release", "verify-release-artifacts.sh"), []byte("#!/bin/sh\nset -eu\nexit 0\n"), 0o755)
-	mustWriteFile(t, filepath.Join(r.root, "scripts", "policy", "check-command-compatibility.sh"), []byte("#!/bin/sh\nset -eu\nexit 0\n"), 0o755)
+	mustWriteFile(t, filepath.Join(r.root, "scripts", "policy", "check-authoritative-interface-baselines.sh"), []byte("#!/bin/sh\nset -eu\nprintf 'cli-compatibility %s\\n' \"$*\"\n"), 0o755)
+	mustWriteFile(t, filepath.Join(r.root, "scripts", "policy", "check-authoritative-schema-compatibility.sh"), []byte("#!/bin/sh\nset -eu\nprintf 'schema-compatibility %s\\n' \"$*\"\n"), 0o755)
 	mustWriteFile(t, filepath.Join(r.root, "Makefile"), []byte("test:\n\t@:\nbuild:\n\t@:\npolicy:\n\t@:\npackage:\n\t@:\n"), 0o644)
 }