diff --git a/.github/env-manifest.yml b/.github/env-manifest.yml
index e66b19f7a..4e41994d3 100644
--- a/.github/env-manifest.yml
+++ b/.github/env-manifest.yml
@@ -159,8 +159,8 @@
 - name: GA4_SERVICE_ACCOUNT_JSON
   kind: secret
   stores: [github, vercel]
-  consumers: [.github/workflows/daily-ga-report.yml, .github/workflows/weekly-ga-report.yml, apps/web/src/modules/ga/config.ts]
-  impact: "GitHub는 GA 리포트가, Vercel은 관리자 대시보드 활성 사용자 그래프가 동작하지 않는다(연결 없음으로 표시)"
+  consumers: [.github/workflows/daily-ga-report.yml, .github/workflows/weekly-ga-report.yml, .github/workflows/seo-monitor.yml, apps/web/src/modules/ga/config.ts]
+  impact: "GitHub는 GA 리포트와 SEO Sheets 적재가, Vercel은 관리자 대시보드 활성 사용자 그래프가 동작하지 않는다(연결 없음으로 표시)"
 
 - name: GA_SHEET_ID
   kind: secret
@@ -168,6 +168,15 @@
   required: false
   consumers: [.github/workflows/weekly-ga-report.yml]
   impact: "주간 GA 수치가 Google Sheets에 쌓이지 않는다(Slack 리포트는 그대로 가고 경고만 남는다)"
+  note: "GA 전용 스프레드시트다. SEO 분석은 SEO_SHEET_ID 로 시트를 나눈다. URL의 /d/와 /edit 사이 ID를 등록하고 서비스 계정에 편집 권한을 준다"
+
+- name: SEO_SHEET_ID
+  kind: secret
+  stores: [github]
+  required: false
+  consumers: [.github/workflows/seo-monitor.yml]
+  impact: "SEO·GSC 장기 이력이 Google Sheets에 쌓이지 않는다(공개 SEO 검사와 원본 아티팩트는 유지된다)"
+  note: "SEO 전용 스프레드시트다. GA 주간 수치(GA_SHEET_ID)와 나눠 쓴다"
 
 - name: GSC_SERVICE_ACCOUNT_JSON
   kind: secret
diff --git a/.github/scripts/lib/google-sheets.mjs b/.github/scripts/lib/google-sheets.mjs
new file mode 100644
index 000000000..bb6e37e6f
--- /dev/null
+++ b/.github/scripts/lib/google-sheets.mjs
@@ -0,0 +1,188 @@
+import { exchangeServiceAccountToken } from "./google-auth.mjs";
+
+/** 첫 컬럼을 고유 키로 사용하여 탭과 헤더를 보장하고 행을 멱등 저장합니다. 호출자는 동시 쓰기를 직렬화해야 합니다. */
+export const upsertGoogleSheetTables = async ({
+	spreadsheetId,
+	serviceAccount,
+	tables,
+	fetcher = fetch,
+	tokenExchanger = exchangeServiceAccountToken,
+	sleep = (milliseconds) =>
+		new Promise((resolve) => setTimeout(resolve, milliseconds)),
+}) => {
+	if (tables.length === 0) {
+		return { updatedRows: 0 };
+	}
+	validateTables(tables);
+	const accessToken = await tokenExchanger({
+		serviceAccount,
+		scope: "https://www.googleapis.com/auth/spreadsheets",
+	});
+	const endpoint = `https://sheets.googleapis.com/v4/spreadsheets/${encodeURIComponent(spreadsheetId)}`;
+	const request = async (path, body) =>
+		await requestSheets({
+			url: `${endpoint}${path}`,
+			body,
+			accessToken,
+			fetcher,
+			sleep,
+		});
+	const spreadsheet = await request("?fields=sheets.properties");
+	const propertiesByTitle = new Map(
+		(spreadsheet.sheets ?? []).map((sheet) => [
+			sheet.properties.title,
+			sheet.properties,
+		]),
+	);
+	const missing = tables.filter((table) => !propertiesByTitle.has(table.title));
+	if (missing.length > 0) {
+		const created = await request(":batchUpdate", {
+			requests: missing.map((table) => ({
+				addSheet: {
+					properties: {
+						title: table.title,
+						gridProperties: {
+							rowCount: Math.max(1000, table.rows.length + 1),
+							columnCount: Math.max(26, table.headers.length),
+						},
+					},
+				},
+			})),
+		});
+		for (const reply of created.replies ?? []) {
+			const properties = reply.addSheet?.properties;
+			if (properties) {
+				propertiesByTitle.set(properties.title, properties);
+			}
+		}
+	}
+	const query = new URLSearchParams();
+	for (const table of tables) {
+		query.append("ranges", `${quoteTitle(table.title)}!1:1`);
+		query.append("ranges", `${quoteTitle(table.title)}!A2:A`);
+	}
+	const existing = await request(`/values:batchGet?${query}`);
+	const data = [];
+	const resizeRequests = [];
+	let updatedRows = 0;
+	for (const [index, table] of tables.entries()) {
+		const header = existing.valueRanges?.[index * 2]?.values?.[0] ?? [];
+		if (
+			header.length > 0 &&
+			JSON.stringify(header) !== JSON.stringify(table.headers)
+		) {
+			throw new Error(`Google Sheets header mismatch: ${table.title}`);
+		}
+		if (header.length === 0) {
+			data.push({
+				range: `${quoteTitle(table.title)}!A1`,
+				values: [table.headers],
+			});
+		}
+		const keys = existing.valueRanges?.[index * 2 + 1]?.values ?? [];
+		const rowByKey = new Map();
+		for (const [offset, cells] of keys.entries()) {
+			if (cells[0] !== undefined && cells[0] !== "") {
+				const key = String(cells[0]);
+				if (rowByKey.has(key)) {
+					throw new Error(
+						`Google Sheets duplicate existing key: ${table.title}`,
+					);
+				}
+				rowByKey.set(key, offset + 2);
+			}
+		}
+		let nextRow = keys.length + 2;
+		for (const row of table.rows) {
+			const key = String(row[0]);
+			const rowNumber = rowByKey.get(key) ?? nextRow++;
+			rowByKey.set(key, rowNumber);
+			data.push({
+				range: `${quoteTitle(table.title)}!A${rowNumber}`,
+				values: [row],
+			});
+			updatedRows += 1;
+		}
+		const properties = propertiesByTitle.get(table.title);
+		if (
+			properties &&
+			(nextRow - 1 > properties.gridProperties.rowCount ||
+				table.headers.length > properties.gridProperties.columnCount)
+		) {
+			resizeRequests.push({
+				updateSheetProperties: {
+					properties: {
+						sheetId: properties.sheetId,
+						gridProperties: {
+							rowCount: Math.max(
+								nextRow - 1,
+								properties.gridProperties.rowCount,
+							),
+							columnCount: Math.max(
+								table.headers.length,
+								properties.gridProperties.columnCount,
+							),
+						},
+					},
+					fields: "gridProperties.rowCount,gridProperties.columnCount",
+				},
+			});
+		}
+	}
+	if (resizeRequests.length > 0) {
+		await request(":batchUpdate", { requests: resizeRequests });
+	}
+	if (data.length > 0) {
+		await request("/values:batchUpdate", { valueInputOption: "RAW", data });
+	}
+
+	return { updatedRows };
+};
+
+const quoteTitle = (title) => `'${title.replaceAll("'", "''")}'`;
+
+const validateTables = (tables) => {
+	const titles = new Set();
+	for (const table of tables) {
+		if (!table.title || titles.has(table.title) || table.headers.length === 0) {
+			throw new Error(
+				"Google Sheets tables must have unique titles and headers",
+			);
+		}
+		titles.add(table.title);
+		const keys = new Set();
+		for (const row of table.rows) {
+			if (
+				!row[0] ||
+				keys.has(String(row[0])) ||
+				row.length !== table.headers.length
+			) {
+				throw new Error(
+					`Google Sheets invalid row or duplicate key: ${table.title}`,
+				);
+			}
+			keys.add(String(row[0]));
+		}
+	}
+};
+
+const requestSheets = async ({ url, body, accessToken, fetcher, sleep }) => {
+	for (let attempt = 0; attempt < 3; attempt += 1) {
+		const response = await fetcher(url, {
+			method: body ? "POST" : "GET",
+			headers: {
+				authorization: `Bearer ${accessToken}`,
+				"content-type": "application/json",
+			},
+			...(body ? { body: JSON.stringify(body) } : {}),
+		});
+		if (response.ok) {
+			return await response.json();
+		}
+		if ((response.status === 429 || response.status >= 500) && attempt < 2) {
+			await sleep(1000 * 2 ** attempt);
+			continue;
+		}
+		throw new Error(`Google Sheets API request failed (${response.status})`);
+	}
+};
diff --git a/.github/scripts/lib/google-sheets.test.ts b/.github/scripts/lib/google-sheets.test.ts
new file mode 100644
index 000000000..f3c92b614
--- /dev/null
+++ b/.github/scripts/lib/google-sheets.test.ts
@@ -0,0 +1,148 @@
+import { describe, expect, it, vi } from "vitest";
+import { upsertGoogleSheetTables } from "./google-sheets.mjs";
+
+const response = (body, status = 200) =>
+	new Response(JSON.stringify(body), { status });
+const properties = {
+	title: "SEO Runs",
+	sheetId: 1,
+	gridProperties: { rowCount: 1000, columnCount: 26 },
+};
+const createOptions = () => ({
+	spreadsheetId: "spreadsheet",
+	serviceAccount: {},
+	tokenExchanger: vi.fn(async () => "token"),
+	sleep: vi.fn(async () => {}),
+	tables: [
+		{
+			title: "SEO Runs",
+			headers: ["key", "count"],
+			rows: [
+				["123:1", 3],
+				["124:1", 4],
+			],
+		},
+	],
+});
+
+describe("upsertGoogleSheetTables", () => {
+	it("없는 탭을 생성하고 헤더와 행을 RAW 배치로 저장한다", async () => {
+		const fetcher = vi
+			.fn()
+			.mockResolvedValueOnce(response({ sheets: [] }))
+			.mockResolvedValueOnce(
+				response({ replies: [{ addSheet: { properties } }] }),
+			)
+			.mockResolvedValueOnce(response({ valueRanges: [{}, {}] }))
+			.mockResolvedValueOnce(response({}));
+		const options = createOptions();
+		expect(await upsertGoogleSheetTables({ ...options, fetcher })).toEqual({
+			updatedRows: 2,
+		});
+		expect(options.tokenExchanger).toHaveBeenCalledWith({
+			serviceAccount: {},
+			scope: "https://www.googleapis.com/auth/spreadsheets",
+		});
+		expect(
+			JSON.parse(fetcher.mock.calls[1][1].body).requests[0].addSheet.properties
+				.title,
+		).toBe("SEO Runs");
+		expect(JSON.parse(fetcher.mock.calls[3][1].body)).toEqual({
+			valueInputOption: "RAW",
+			data: [
+				{ range: "'SEO Runs'!A1", values: [["key", "count"]] },
+				{ range: "'SEO Runs'!A2", values: [["123:1", 3]] },
+				{ range: "'SEO Runs'!A3", values: [["124:1", 4]] },
+			],
+		});
+	});
+	it("기존 키는 같은 행에 갱신하고 신규 키만 마지막에 추가한다", async () => {
+		const fetcher = vi
+			.fn()
+			.mockResolvedValueOnce(response({ sheets: [{ properties }] }))
+			.mockResolvedValueOnce(
+				response({
+					valueRanges: [
+						{ values: [["key", "count"]] },
+						{ values: [["old"], ["123:1"]] },
+					],
+				}),
+			)
+			.mockResolvedValueOnce(response({}));
+		await upsertGoogleSheetTables({ ...createOptions(), fetcher });
+		expect(JSON.parse(fetcher.mock.calls[2][1].body).data).toEqual([
+			{ range: "'SEO Runs'!A3", values: [["123:1", 3]] },
+			{ range: "'SEO Runs'!A4", values: [["124:1", 4]] },
+		]);
+	});
+	it("데이터가 그리드를 넘어가면 쓰기 전에 확장한다", async () => {
+		const fetcher = vi
+			.fn()
+			.mockResolvedValueOnce(
+				response({
+					sheets: [
+						{
+							properties: {
+								...properties,
+								gridProperties: { rowCount: 2, columnCount: 1 },
+							},
+						},
+					],
+				}),
+			)
+			.mockResolvedValueOnce(
+				response({
+					valueRanges: [{ values: [["key", "count"]] }, { values: [["old"]] }],
+				}),
+			)
+			.mockResolvedValueOnce(response({}))
+			.mockResolvedValueOnce(response({}));
+		await upsertGoogleSheetTables({ ...createOptions(), fetcher });
+		expect(
+			JSON.parse(fetcher.mock.calls[2][1].body).requests[0]
+				.updateSheetProperties.properties.gridProperties,
+		).toEqual({ rowCount: 4, columnCount: 2 });
+	});
+	it("헤더가 다르면 기존 데이터를 덮어쓰지 않는다", async () => {
+		const fetcher = vi
+			.fn()
+			.mockResolvedValueOnce(response({ sheets: [{ properties }] }))
+			.mockResolvedValueOnce(
+				response({ valueRanges: [{ values: [["unexpected"]] }, {}] }),
+			);
+		await expect(
+			upsertGoogleSheetTables({ ...createOptions(), fetcher }),
+		).rejects.toThrow("header mismatch");
+		expect(fetcher).toHaveBeenCalledTimes(2);
+	});
+	it("429와 5xx 오류를 지수 백오프로 재시도한다", async () => {
+		const fetcher = vi
+			.fn()
+			.mockResolvedValueOnce(response({}, 429))
+			.mockResolvedValueOnce(response({}, 503))
+			.mockResolvedValueOnce(response({ sheets: [{ properties }] }))
+			.mockResolvedValueOnce(response({ valueRanges: [{}, {}] }))
+			.mockResolvedValueOnce(response({}));
+		const options = createOptions();
+		await upsertGoogleSheetTables({ ...options, fetcher });
+		expect(options.sleep.mock.calls).toEqual([[1000], [2000]]);
+	});
+	it("재시도는 세 번까지이며 인증 오류는 재시도하지 않는다", async () => {
+		for (const status of [503, 403]) {
+			const fetcher = vi.fn(async () => response({}, status));
+			await expect(
+				upsertGoogleSheetTables({ ...createOptions(), fetcher }),
+			).rejects.toThrow(`(${status})`);
+			expect(fetcher).toHaveBeenCalledTimes(status === 503 ? 3 : 1);
+		}
+	});
+	it("입력 키가 중복되면 요청 전에 거절한다", async () => {
+		const options = createOptions();
+		options.tables[0].rows.push(["123:1", 5]);
+		const fetcher = vi.fn();
+		await expect(
+			upsertGoogleSheetTables({ ...options, fetcher }),
+		).rejects.toThrow("duplicate key");
+		expect(fetcher).not.toHaveBeenCalled();
+	});
+});
diff --git a/.github/scripts/lib/seo-sheets.mjs b/.github/scripts/lib/seo-sheets.mjs
new file mode 100644
index 000000000..4064faf87
--- /dev/null
+++ b/.github/scripts/lib/seo-sheets.mjs
@@ -0,0 +1,300 @@
+import { createSeoObservationMap } from "./seo-history.mjs";
+/** SEO/GSC 보고서를 분석용 시트 행과 수동 변경 기록 탭으로 변환합니다. 비율은 0~1이며 분모가 없으면 빈 셀입니다. */
+export const createSeoSheetTables = ({
+	seoReport,
+	gscReport,
+	githubRunId,
+	githubRunAttempt,
+	commitSha = "",
+	runUrl = "",
+}) => {
+	if (!githubRunId || !githubRunAttempt || !Array.isArray(seoReport?.pages)) {
+		throw new Error("SEO Sheets requires a run ID, attempt and SEO report");
+	}
+	const runKey = `${githubRunId}:${githubRunAttempt}`;
+	const context = [
+		runKey,
+		seoReport.generatedAt ?? "",
+		String(githubRunId),
+		String(githubRunAttempt),
+	];
+	const pageGroups = new Map();
+	const observations = createSeoObservationMap(seoReport);
+	for (const page of seoReport.pages.filter((page) => page.kind === "page")) {
+		const pages = pageGroups.get(page.url) ?? [];
+		pages.push(page);
+		pageGroups.set(page.url, pages);
+	}
+	const groups = [...pageGroups.values()];
+	const observedGroups = groups.filter((pages) =>
+		pages.every((page) =>
+			observations.get([page.kind, page.url, page.agent].join("\u001f")),
+		),
+	);
+	const errorPageCount = groups.filter((pages) =>
+		pages.some((page) =>
+			page.issues.some((issue) => issue.severity === "error"),
+		),
+	).length;
+	const warningPageCount = groups.filter((pages) =>
+		pages.some((page) =>
+			page.issues.some((issue) => issue.severity === "warning"),
+		),
+	).length;
+	const healthyPageCount = observedGroups.filter((pages) =>
+		pages.every((page) => page.issues.length === 0),
+	).length;
+	const ratio = (count) => (groups.length > 0 ? count / groups.length : "");
+	const delta = seoReport.history?.delta ?? {};
+	const baselineStatus = seoReport.history?.baselineStatus ?? "missing";
+	const issueRows = [];
+	if (baselineStatus === "compatible") {
+		for (const state of ["new", "resolved", "unobservable"]) {
+			for (const issue of delta[state] ?? []) {
+				const issueKey =
+					issue.key ??
+					JSON.stringify([
+						issue.kind,
+						issue.url,
+						issue.agent,
+						issue.code,
+						issue.field,
+					]);
+				issueRows.push([
+					JSON.stringify([runKey, state, issueKey]),
+					...context,
+					state,
+					issueKey,
+					issue.kind ?? "",
+					issue.url ?? "",
+					issue.agent ?? "",
+					issue.code ?? "",
+					issue.field ?? "",
+					issue.severity ?? "",
+					issue.message ?? "",
+				]);
+			}
+		}
+	}
+	const hasGsc = gscReport && gscReport.status !== "skipped";
+	const inspections = hasGsc ? (gscReport.inspections ?? []) : [];
+	const weekly = hasGsc ? gscReport.weekly : null;
+	const summary = {
+		key: runKey,
+		generatedAt: context[1],
+		githubRunId: context[2],
+		githubRunAttempt: context[3],
+		commitSha,
+		runUrl,
+		status: seoReport.errors > 0 ? "failed" : "passed",
+		requestCount: seoReport.pages.length,
+		pageCount: groups.length,
+		observedPageCount: observedGroups.length,
+		errorCount: seoReport.errors ?? 0,
+		warningCount: seoReport.warnings ?? 0,
+		errorPageCount,
+		warningPageCount,
+		healthyPageCount,
+		errorPageRatio: ratio(errorPageCount),
+		warningPageRatio: ratio(warningPageCount),
+		healthyPageRatio: ratio(healthyPageCount),
+		baselineStatus,
+		newCount: delta.new?.length ?? 0,
+		persistentCount: delta.persistent?.length ?? 0,
+		resolvedCount: delta.resolved?.length ?? 0,
+		unobservableCount: delta.unobservable?.length ?? 0,
+		gscStatus: gscReport?.status ?? "missing",
+		gscInspectionCount: inspections.length,
+		gscFailureCount: gscReport?.failures?.length ?? 0,
+		...createWeeklySummary(weekly),
+	};
+
+	return [
+		{
+			title: "SEO Runs",
+			headers: Object.keys(summary),
+			rows: [Object.values(summary)],
+		},
+		{
+			title: "SEO Issue Events",
+			headers: [
+				"key",
+				"runKey",
+				"generatedAt",
+				"githubRunId",
+				"githubRunAttempt",
+				"state",
+				"issueKey",
+				"kind",
+				"url",
+				"agent",
+				"code",
+				"field",
+				"severity",
+				"message",
+			],
+			rows: issueRows,
+		},
+		{
+			title: "GSC Index",
+			headers: [
+				"key",
+				"runKey",
+				"generatedAt",
+				"githubRunId",
+				"githubRunAttempt",
+				"inspectedAt",
+				"siteUrl",
+				"url",
+				"verdict",
+				"coverageState",
+				"indexingState",
+				"robotsTxtState",
+				"pageFetchState",
+				"lastCrawlTime",
+				"googleCanonical",
+				"userCanonical",
+			],
+			rows: inspections.map((inspection) => [
+				JSON.stringify([runKey, inspection.url]),
+				...context,
+				gscReport.generatedAt ?? "",
+				gscReport.siteUrl ?? "",
+				...[
+					"url",
+					"verdict",
+					"coverageState",
+					"indexingState",
+					"robotsTxtState",
+					"pageFetchState",
+					"lastCrawlTime",
+					"googleCanonical",
+					"userCanonical",
+				].map((field) => inspection[field] ?? ""),
+			]),
+		},
+		{
+			title: "GSC Performance",
+			headers: [
+				"key",
+				"runKey",
+				"generatedAt",
+				"githubRunId",
+				"githubRunAttempt",
+				"siteUrl",
+				"period",
+				"startDate",
+				"endDate",
+				"dimension",
+				"value",
+				"clicks",
+				"impressions",
+				"ctr",
+				"position",
+			],
+			rows: createPerformanceRows({
+				weekly,
+				context,
+				siteUrl: gscReport?.siteUrl ?? "",
+			}),
+		},
+		{
+			title: "SEO Changes",
+			headers: [
+				"key",
+				"date",
+				"commitSha",
+				"prUrl",
+				"summary",
+				"affectedUrls",
+				"notes",
+			],
+			rows: [],
+		},
+	];
+};
+
+const createWeeklySummary = (weekly) => {
+	const summary = {};
+	for (const period of ["current", "previous"]) {
+		for (const metric of ["clicks", "impressions", "ctr", "position"]) {
+			summary[`${period}${metric[0].toUpperCase()}${metric.slice(1)}`] =
+				weekly?.[period]?.[metric] ?? "";
+		}
+	}
+	for (const metric of ["clicks", "impressions", "ctr", "position"]) {
+		const current = weekly?.current?.[metric];
+		const previous = weekly?.previous?.[metric];
+		const isRatio = metric === "clicks" || metric === "impressions";
+		let change = "";
+		if (Number.isFinite(current) && Number.isFinite(previous)) {
+			if (!isRatio) {
+				change = current - previous;
+			} else if (previous !== 0) {
+				change = (current - previous) / previous;
+			}
+		}
+		summary[`${metric}Change${isRatio ? "Ratio" : "Amount"}`] = change;
+	}
+
+	return summary;
+};
+
+const createPerformanceRows = ({ weekly, context, siteUrl }) => {
+	if (!weekly) {
+		return [];
+	}
+	const rows = [];
+	const add = ({ metric, period, dimension, startDate, endDate }) => {
+		if (!metric) {
+			return;
+		}
+		const value = metric.keys?.[0] ?? "";
+		rows.push([
+			JSON.stringify([
+				context[0],
+				period,
+				startDate,
+				endDate,
+				dimension,
+				value,
+			]),
+			...context,
+			siteUrl,
+			period,
+			startDate,
+			endDate,
+			dimension,
+			value,
+			metric.clicks ?? 0,
+			metric.impressions ?? 0,
+			metric.ctr ?? 0,
+			metric.position ?? 0,
+		]);
+	};
+	for (const period of ["current", "previous"]) {
+		add({
+			metric: weekly[period],
+			period,
+			dimension: "total",
+			startDate: weekly.week[period === "current" ? "start" : "previousStart"],
+			endDate: weekly.week[period === "current" ? "end" : "previousEnd"],
+		});
+	}
+	for (const [dimension, metrics] of [
+		["query", weekly.topQueries],
+		["page", weekly.topPages],
+	]) {
+		for (const metric of metrics ?? []) {
+			add({
+				metric,
+				period: "current",
+				dimension,
+				startDate: weekly.week.start,
+				endDate: weekly.week.end,
+			});
+		}
+	}
+
+	return rows;
+};
diff --git a/.github/scripts/lib/seo-sheets.test.ts b/.github/scripts/lib/seo-sheets.test.ts
new file mode 100644
index 000000000..86cbf2f6d
--- /dev/null
+++ b/.github/scripts/lib/seo-sheets.test.ts
@@ -0,0 +1,249 @@
+import { describe, expect, it } from "vitest";
+import { createSeoSheetTables } from "./seo-sheets.mjs";
+
+const createReport = () => ({
+	generatedAt: "2026-09-22T00:17:00Z",
+	errors: 1,
+	warnings: 1,
+	pages: [
+		{
+			kind: "page",
+			url: "https://example.com/a",
+			agent: "pc",
+			status: 200,
+			metadata: {},
+			issues: [{ severity: "warning" }],
+		},
+		{
+			kind: "page",
+			url: "https://example.com/a",
+			agent: "mobile",
+			status: 200,
+			metadata: {},
+			issues: [],
+		},
+		{
+			kind: "page",
+			url: "https://example.com/b",
+			agent: "pc",
+			status: null,
+			failure: "timeout",
+			issues: [{ severity: "error" }],
+		},
+		{
+			kind: "robots",
+			url: "https://example.com/robots.txt",
+			agent: "pc",
+			status: 200,
+			issues: [],
+		},
+	],
+	history: {
+		baselineStatus: "compatible",
+		delta: {
+			new: [
+				{
+					key: "issue-a",
+					url: "https://example.com/a",
+					code: "TITLE",
+					severity: "warning",
+				},
+			],
+			persistent: [{ key: "persistent" }],
+			resolved: [{ key: "resolved" }],
+			unobservable: [{ key: "unobservable" }],
+		},
+	},
+});
+
+const metadata = {
+	githubRunId: "123",
+	githubRunAttempt: "1",
+	commitSha: "sha",
+	runUrl: "https://github.com/run/123",
+};
+const record = (table) =>
+	Object.fromEntries(
+		table.headers.map((header, index) => [header, table.rows[0][index]]),
+	);
+
+describe("createSeoSheetTables", () => {
+	it("고유 URL의 관측 및 오류 비율과 변화 이벤트만 생성한다", () => {
+		const tables = createSeoSheetTables({
+			...metadata,
+			seoReport: createReport(),
+		});
+		expect(record(tables[0])).toMatchObject({
+			key: "123:1",
+			requestCount: 4,
+			pageCount: 2,
+			observedPageCount: 1,
+			errorPageRatio: 0.5,
+			warningPageRatio: 0.5,
+			healthyPageRatio: 0,
+			persistentCount: 1,
+			gscStatus: "missing",
+		});
+		expect(tables[1].rows.map((row) => row[5])).toEqual([
+			"new",
+			"resolved",
+			"unobservable",
+		]);
+		for (const table of tables) {
+			for (const row of table.rows) {
+				expect(row).toHaveLength(table.headers.length);
+			}
+		}
+	});
+	it("최초 기준선은 이벤트를 만들지 않고 빈 분모는 0%로 오인하지 않는다", () => {
+		const seoReport = createReport();
+		seoReport.history.baselineStatus = "missing";
+		seoReport.pages = [];
+		const tables = createSeoSheetTables({ ...metadata, seoReport });
+		expect(tables[1].rows).toEqual([]);
+		expect(record(tables[0])).toMatchObject({
+			baselineStatus: "missing",
+			pageCount: 0,
+			observedPageCount: 0,
+			errorPageRatio: "",
+			healthyPageRatio: "",
+		});
+	});
+	it("GSC skipped 상태는 실행에 남기고 GSC 행은 생성하지 않는다", () => {
+		const tables = createSeoSheetTables({
+			...metadata,
+			seoReport: createReport(),
+			gscReport: { status: "skipped", inspections: [{ url: "ignored" }] },
+		});
+		expect(record(tables[0]).gscStatus).toBe("skipped");
+		expect(tables[2].rows).toEqual([]);
+		expect(tables[3].rows).toEqual([]);
+		expect(record(tables[0])).toMatchObject({
+			currentClicks: "",
+			previousClicks: "",
+			clicksChangeRatio: "",
+			positionChangeAmount: "",
+		});
+	});
+	it("색인 스냅샷과 기간이 구분되는 주간 전체 및 상위 지표를 저장한다", () => {
+		const metric = {
+			keys: [],
+			clicks: 3,
+			impressions: 10,
+			ctr: 0.3,
+			position: 4,
+		};
+		const tables = createSeoSheetTables({
+			...metadata,
+			seoReport: createReport(),
+			gscReport: {
+				status: "passed",
+				generatedAt: "2026-09-22",
+				siteUrl: "https://example.com/",
+				inspections: [
+					{
+						url: "https://example.com/a",
+						verdict: "PASS",
+						googleCanonical: "https://example.com/a",
+					},
+				],
+				weekly: {
+					week: {
+						start: "2026-09-12",
+						end: "2026-09-18",
+						previousStart: "2026-09-05",
+						previousEnd: "2026-09-11",
+					},
+					current: metric,
+					previous: { ...metric, clicks: 2 },
+					topQueries: [{ ...metric, keys: ["=SUM(A1)"] }],
+					topPages: [{ ...metric, keys: ["https://example.com/a"] }],
+				},
+			},
+		});
+		expect(record(tables[2])).toMatchObject({
+			verdict: "PASS",
+			googleCanonical: "https://example.com/a",
+		});
+		expect(tables[3].rows.map((row) => row.slice(6, 12))).toEqual([
+			["current", "2026-09-12", "2026-09-18", "total", "", 3],
+			["previous", "2026-09-05", "2026-09-11", "total", "", 2],
+			["current", "2026-09-12", "2026-09-18", "query", "=SUM(A1)", 3],
+			[
+				"current",
+				"2026-09-12",
+				"2026-09-18",
+				"page",
+				"https://example.com/a",
+				3,
+			],
+		]);
+		expect(new Set(tables[3].rows.map((row) => row[0])).size).toBe(4);
+		expect(record(tables[0])).toMatchObject({
+			currentClicks: 3,
+			previousClicks: 2,
+			currentImpressions: 10,
+			previousImpressions: 10,
+			currentCtr: 0.3,
+			previousCtr: 0.3,
+			currentPosition: 4,
+			previousPosition: 4,
+			clicksChangeRatio: 0.5,
+			impressionsChangeRatio: 0,
+			ctrChangeAmount: 0,
+			positionChangeAmount: 0,
+		});
+	});
+	it("수동 변경 기록 탭의 헤더만 만들고 자동 행을 추가하지 않는다", () => {
+		const tables = createSeoSheetTables({
+			...metadata,
+			seoReport: createReport(),
+		});
+		expect(tables[4]).toEqual({
+			title: "SEO Changes",
+			headers: [
+				"key",
+				"date",
+				"commitSha",
+				"prUrl",
+				"summary",
+				"affectedUrls",
+				"notes",
+			],
+			rows: [],
+		});
+	});
+	it("직전 기간 분모가 0이면 변화율을 비워 두고 CTR과 순위는 차이를 남긴다", () => {
+		const tables = createSeoSheetTables({
+			...metadata,
+			seoReport: createReport(),
+			gscReport: {
+				status: "passed",
+				weekly: {
+					week: {
+						start: "2026-09-12",
+						end: "2026-09-18",
+						previousStart: "2026-09-05",
+						previousEnd: "2026-09-11",
+					},
+					current: { clicks: 5, impressions: 10, ctr: 0.5, position: 3 },
+					previous: { clicks: 0, impressions: 0, ctr: 0, position: 5 },
+				},
+			},
+		});
+		expect(record(tables[0])).toMatchObject({
+			clicksChangeRatio: "",
+			impressionsChangeRatio: "",
+			ctrChangeAmount: 0.5,
+			positionChangeAmount: -2,
+		});
+	});
+	it("동일 attempt는 동일 키, 다른 attempt는 다른 키를 생성한다", () => {
+		const input = { ...metadata, seoReport: createReport() };
+		const tables = createSeoSheetTables(input);
+		expect(createSeoSheetTables(input)).toEqual(tables);
+		expect(
+			createSeoSheetTables({ ...input, githubRunAttempt: "2" })[1].rows[0][0],
+		).not.toBe(tables[1].rows[0][0]);
+	});
+});
diff --git a/.github/scripts/persist-seo-sheets.mjs b/.github/scripts/persist-seo-sheets.mjs
new file mode 100644
index 000000000..47704020c
--- /dev/null
+++ b/.github/scripts/persist-seo-sheets.mjs
@@ -0,0 +1,116 @@
+import { appendFile, readFile } from "node:fs/promises";
+import { resolve } from "node:path";
+import { pathToFileURL } from "node:url";
+
+import { upsertGoogleSheetTables } from "./lib/google-sheets.mjs";
+import { createSeoSheetTables } from "./lib/seo-sheets.mjs";
+
+/**
+ * SEO 분석을 쌓을 Google Sheets 스프레드시트 ID 환경 변수입니다.
+ * @description GA 주간 수치(GA_SHEET_ID)와 시트를 나눕니다. 한 ID를 두 작업이 함께 쓰면 한쪽이 값을 바꿨을 때 다른 쪽이 조용히 남의 시트에 씁니다.
+ */
+export const SEO_SHEET_ID_ENV = "SEO_SHEET_ID";
+
+/**
+ * SEO·GSC 보고서를 분석용 Google Sheets 행으로 멱등 적재합니다.
+ * @description 시트 설정이 없으면 공개 SEO 검사를 막지 않고 건너뜁니다. 설정이 있는데 API 적재가 실패하면 장기 이력 누락을 숨기지 않도록 예외를 전파합니다.
+ */
+export const persistSeoReportsToSheets = async ({
+	spreadsheetId = process.env.SEO_SHEET_ID,
+	serviceAccountJson = process.env.GA4_SERVICE_ACCOUNT_JSON,
+	githubRunId = process.env.GITHUB_RUN_ID,
+	githubRunAttempt = process.env.GITHUB_RUN_ATTEMPT ?? "1",
+	commitSha = process.env.GITHUB_SHA ?? "",
+	runUrl = createGithubRunUrl(process.env),
+	stepSummaryPath = process.env.GITHUB_STEP_SUMMARY,
+} = {}) => {
+	if (!spreadsheetId || !serviceAccountJson) {
+		const missingNames = [
+			!spreadsheetId && SEO_SHEET_ID_ENV,
+			!serviceAccountJson && "GA4_SERVICE_ACCOUNT_JSON",
+		].filter(Boolean);
+		const message = `Google Sheets 적재 건너뜀: ${missingNames.join(", ")} 없음`;
+		console.warn(`::warning::${message}`);
+		await appendStepSummary({ stepSummaryPath, message });
+
+		return { status: "skipped", updatedRows: 0 };
+	}
+	if (!githubRunId) {
+		throw new Error("GITHUB_RUN_ID가 없어 Sheets 행의 멱등 키를 만들 수 없습니다.");
+	}
+
+	const [seoReport, gscReport] = await Promise.all([
+		readJson("artifacts/seo/seo-report.json"),
+		readOptionalJson("artifacts/seo/gsc-report.json"),
+	]);
+	const serviceAccount = parseServiceAccount(serviceAccountJson);
+	const tables = createSeoSheetTables({
+		seoReport,
+		gscReport,
+		githubRunId,
+		githubRunAttempt,
+		commitSha,
+		runUrl,
+	});
+	const result = await upsertGoogleSheetTables({
+		spreadsheetId,
+		serviceAccount,
+		tables,
+	});
+	const message = `Google Sheets SEO 분석 행 ${result.updatedRows}건 적재`;
+	console.log(message);
+	await appendStepSummary({ stepSummaryPath, message });
+
+	return { status: "stored", ...result };
+};
+
+const readJson = async (path) => JSON.parse(await readFile(path, "utf8"));
+
+const readOptionalJson = async (path) => {
+	try {
+		return await readJson(path);
+	} catch (error) {
+		if (error?.code === "ENOENT") {
+			return null;
+		}
+
+		throw error;
+	}
+};
+
+const parseServiceAccount = (serviceAccountJson) => {
+	try {
+		const serviceAccount = JSON.parse(serviceAccountJson);
+		if (!serviceAccount.client_email || !serviceAccount.private_key) {
+			throw new Error("required fields missing");
+		}
+
+		return serviceAccount;
+	} catch {
+		throw new Error("GA4_SERVICE_ACCOUNT_JSON 형식이 올바르지 않습니다.");
+	}
+};
+
+const createGithubRunUrl = (environment) => {
+	const { GITHUB_SERVER_URL, GITHUB_REPOSITORY, GITHUB_RUN_ID } = environment;
+	if (!GITHUB_SERVER_URL || !GITHUB_REPOSITORY || !GITHUB_RUN_ID) {
+		return "";
+	}
+
+	return `${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}/actions/runs/${GITHUB_RUN_ID}`;
+};
+
+const appendStepSummary = async ({ stepSummaryPath, message }) => {
+	if (!stepSummaryPath) {
+		return;
+	}
+
+	await appendFile(stepSummaryPath, `\n## SEO 장기 이력\n\n${message}\n`);
+};
+
+if (
+	process.argv[1] &&
+	pathToFileURL(resolve(process.argv[1])).href === import.meta.url
+) {
+	await persistSeoReportsToSheets();
+}
diff --git a/.github/scripts/persist-seo-sheets.test.ts b/.github/scripts/persist-seo-sheets.test.ts
new file mode 100644
index 000000000..d4a353807
--- /dev/null
+++ b/.github/scripts/persist-seo-sheets.test.ts
@@ -0,0 +1,103 @@
+// @ts-nocheck — .mjs 스크립트를 직접 import 하는 테스트라 타입 선언이 없습니다.
+import { appendFile, readFile } from "node:fs/promises";
+import { afterEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("node:fs/promises", () => ({
+	appendFile: vi.fn(),
+	readFile: vi.fn(),
+}));
+vi.mock("./lib/seo-sheets.mjs", () => ({
+	createSeoSheetTables: vi.fn(() => [
+		{ title: "SEO Runs", headers: ["key"], rows: [["1:1"]] },
+	]),
+}));
+vi.mock("./lib/google-sheets.mjs", () => ({
+	upsertGoogleSheetTables: vi.fn(async () => ({ updatedRows: 1 })),
+}));
+
+import { persistSeoReportsToSheets } from "./persist-seo-sheets.mjs";
+import { upsertGoogleSheetTables } from "./lib/google-sheets.mjs";
+import { createSeoSheetTables } from "./lib/seo-sheets.mjs";
+
+afterEach(() => {
+	vi.clearAllMocks();
+	vi.unstubAllEnvs();
+});
+
+describe("SEO Google Sheets 적재 CLI", () => {
+	it("설정이 없으면 검사를 실패시키지 않고 건너뛴다", async () => {
+		const result = await persistSeoReportsToSheets({
+			spreadsheetId: "",
+			serviceAccountJson: "",
+		});
+
+		expect(result).toEqual({ status: "skipped", updatedRows: 0 });
+		expect(readFile).not.toHaveBeenCalled();
+		expect(upsertGoogleSheetTables).not.toHaveBeenCalled();
+	});
+
+	it("보고서를 읽고 실행 키와 함께 멱등 적재한다", async () => {
+		readFile
+			.mockResolvedValueOnce(JSON.stringify({ generatedAt: "2026-09-22T00:00:00Z" }))
+			.mockResolvedValueOnce(JSON.stringify({ status: "passed" }));
+		const result = await persistSeoReportsToSheets({
+			spreadsheetId: "sheet-id",
+			serviceAccountJson: JSON.stringify({
+				client_email: "reporter@example.test",
+				private_key: "private-key",
+			}),
+			githubRunId: "123",
+			githubRunAttempt: "2",
+			commitSha: "abc",
+			runUrl: "https://github.test/run/123",
+			stepSummaryPath: "/tmp/summary.md",
+		});
+
+		expect(createSeoSheetTables).toHaveBeenCalledWith(
+			expect.objectContaining({
+				githubRunId: "123",
+				githubRunAttempt: "2",
+				commitSha: "abc",
+			}),
+		);
+		expect(upsertGoogleSheetTables).toHaveBeenCalledWith(
+			expect.objectContaining({ spreadsheetId: "sheet-id" }),
+		);
+		expect(appendFile).toHaveBeenCalledWith(
+			"/tmp/summary.md",
+			expect.stringContaining("1건 적재"),
+		);
+		expect(result).toEqual({ status: "stored", updatedRows: 1 });
+	});
+
+	it("서비스 계정 JSON이 잘못되었으면 적재를 실패로 표시한다", async () => {
+		readFile.mockResolvedValue("{}");
+
+		await expect(
+			persistSeoReportsToSheets({
+				spreadsheetId: "sheet-id",
+				serviceAccountJson: "{}",
+				githubRunId: "123",
+			}),
+		).rejects.toThrow("GA4_SERVICE_ACCOUNT_JSON 형식");
+	});
+
+	it("GSC 보고서가 없어도 SEO 요약은 적재한다", async () => {
+		readFile
+			.mockResolvedValueOnce(JSON.stringify({ generatedAt: "2026-09-22T00:00:00Z" }))
+			.mockRejectedValueOnce(Object.assign(new Error("not found"), { code: "ENOENT" }));
+
+		await persistSeoReportsToSheets({
+			spreadsheetId: "sheet-id",
+			serviceAccountJson: JSON.stringify({
+				client_email: "reporter@example.test",
+				private_key: "private-key",
+			}),
+			githubRunId: "123",
+		});
+
+		expect(createSeoSheetTables).toHaveBeenCalledWith(
+			expect.objectContaining({ gscReport: null }),
+		);
+	});
+});
diff --git a/.github/workflows/seo-monitor.yml b/.github/workflows/seo-monitor.yml
index d14366cf0..56afce0e8 100644
--- a/.github/workflows/seo-monitor.yml
+++ b/.github/workflows/seo-monitor.yml
@@ -68,6 +68,13 @@ jobs:
           SLACK_REPORT_WEBHOOK_URL: ${{ secrets.SLACK_REPORT_WEBHOOK_URL }}
         run: node .github/scripts/notify-seo-slack.mjs
 
+      - name: Persist SEO analytics to Google Sheets
+        if: ${{ always() }}
+        env:
+          SEO_SHEET_ID: ${{ secrets.SEO_SHEET_ID }}
+          GA4_SERVICE_ACCOUNT_JSON: ${{ secrets.GA4_SERVICE_ACCOUNT_JSON }}
+        run: pnpm seo:sheets
+
       - name: Upload SEO report
         if: ${{ always() }}
         uses: actions/upload-artifact@v6
diff --git a/docs/architecture.md b/docs/architecture.md
index b2b660e2c..1296a7cd5 100644
--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -23,6 +23,14 @@
 | 모니터링 | Sentry (웹·확장·앱) |
 | i18n | ko/en. 웹은 `apps/web/src/modules/i18n/`(`util.client` / `util.server`), 확장은 `_locales/`. **`lng === "ko"` 분기를 쓰지 않고 항상 번역 키를 씁니다** |
 
+### SEO 장기 이력
+
+`seo-monitor.yml`은 원본 보고서를 Actions 아티팩트로 30일 보관하고, 실행 요약·이슈
+변경·GSC 색인·주간 성과는 `SEO_SHEET_ID`의 Google Sheets에 멱등
+적재합니다. Google Sheets 인증은 기존 `GA4_SERVICE_ACCOUNT_JSON`을 재사용하며, 해당
+서비스 계정은 대상 스프레드시트의 편집자여야 합니다. GSC 주간 성과는
+태평양 시간대의 월요일에 수집됩니다.
+
 ## 프론트엔드
 
 | 항목 | 내용 |
diff --git a/docs/environment-variables.md b/docs/environment-variables.md
index 0f216c83f..8fb64593d 100644
--- a/docs/environment-variables.md
+++ b/docs/environment-variables.md
@@ -46,7 +46,7 @@
 
 <!-- env-manifest:start -->
 
-### GitHub Secrets (23개)
+### GitHub Secrets (24개)
 
 | 이름 | 없으면 생기는 일 | 읽는 곳 |
 | --- | --- | --- |
@@ -59,11 +59,12 @@
 | `EXPO_ASC_API_KEY_P8` | TestFlight 제출과 App Store 현황 조회가 실패한다 | `.github/workflows/cd-app.yml`, `.github/workflows/ci.yml`, `.github/workflows/versions.yml` |
 | `EXPO_TOKEN` | EAS 로그인이 실패해 앱 빌드가 멈춘다 | `.github/workflows/cd-app.yml` |
 | `GA_SHEET_ID` (선택) | 주간 GA 수치가 Google Sheets에 쌓이지 않는다(Slack 리포트는 그대로 가고 경고만 남는다) | `.github/workflows/weekly-ga-report.yml` |
-| `GA4_SERVICE_ACCOUNT_JSON` | GitHub는 GA 리포트가, Vercel은 관리자 대시보드 활성 사용자 그래프가 동작하지 않는다(연결 없음으로 표시) | `.github/workflows/daily-ga-report.yml`, `.github/workflows/weekly-ga-report.yml`, `apps/web/src/modules/ga/config.ts` |
+| `GA4_SERVICE_ACCOUNT_JSON` | GitHub는 GA 리포트와 SEO Sheets 적재가, Vercel은 관리자 대시보드 활성 사용자 그래프가 동작하지 않는다(연결 없음으로 표시) | `.github/workflows/daily-ga-report.yml`, `.github/workflows/weekly-ga-report.yml`, `.github/workflows/seo-monitor.yml`, `apps/web/src/modules/ga/config.ts` |
 | `GSC_SERVICE_ACCOUNT_JSON` (선택) | 없으면 공개 SEO 검사는 계속 실행되지만 Search Console 색인 상태와 주간 검색 성과 조회를 건너뛴다 | `.github/workflows/seo-monitor.yml` |
 | `NOTION_TOKEN` | 주간 리팩토링 점검 결과가 노션 작업 카드로 만들어지지 않는다 | `.github/workflows/refactor-audit.yml` |
 | `REFRESH_TOKEN` | 크롬 웹스토어 API 인증이 실패해 확장 배포와 스토어 현황 조회가 멈춘다 | `.github/workflows/cd-extension.yml`, `.github/workflows/ci.yml`, `.github/workflows/versions.yml` |
 | `SENTRY_AUTH_TOKEN` | Sentry 소스맵 업로드가 조용히 실패한다. 빌드는 통과하므로 스택 트레이스가 난독화된 채 보여야 알게 된다 | `.github/workflows/cd-extension.yml`, `apps/web/next.config.mjs`, `packages/vite-config/lib/withPageConfig.mjs` |
+| `SEO_SHEET_ID` (선택) | SEO·GSC 장기 이력이 Google Sheets에 쌓이지 않는다(공개 SEO 검사와 원본 아티팩트는 유지된다) | `.github/workflows/seo-monitor.yml` |
 | `SLACK_BOT_TOKEN` | GitHub는 머지 스레드 생성과 댓글이, Vercel은 Slack 배포 모달이 동작하지 않는다 | `.github/workflows/ci.yml`, `apps/web/src/modules/slack/config.ts` |
 | `SLACK_CHANNEL_ID` | 머지 스레드가 생기지 않고 웹훅 알림으로 폴백한다 | `.github/workflows/ci.yml` |
 | `SLACK_REPORT_WEBHOOK_URL` | GA 리포트, 주간 리팩토링 점검 결과, 조치가 필요한 SEO 감사 결과가 전용 채널로 게시되지 않는다 | `.github/workflows/daily-ga-report.yml`, `.github/workflows/weekly-ga-report.yml`, `.github/workflows/refactor-audit.yml`, `.github/workflows/seo-monitor.yml` |
@@ -81,7 +82,7 @@
 | `BUILD_ENV` | production, preview | Git 연동 빌드가 development로 구워져 운영에 localhost:3000이 실린다. tsup.config.ts의 가드가 빌드를 실패시켜 막는다 | `packages/env/src/config.ts`, `packages/env/tsup.config.ts`, `apps/web/next.config.mjs`, `packages/zipper/index.ts` |
 | `ENABLE_EXPERIMENTAL_COREPACK` | 전체 | corepack이 꺼져 packageManager의 pnpm 버전이 무시된다 | 코드 밖 |
 | `GA4_PROPERTY_ID` (선택) | 전체 | 없으면 코드에 적힌 기본 속성 ID로 동작한다 | `apps/web/src/modules/ga/config.ts` |
-| `GA4_SERVICE_ACCOUNT_JSON` | 전체 | GitHub는 GA 리포트가, Vercel은 관리자 대시보드 활성 사용자 그래프가 동작하지 않는다(연결 없음으로 표시) | `.github/workflows/daily-ga-report.yml`, `.github/workflows/weekly-ga-report.yml`, `apps/web/src/modules/ga/config.ts` |
+| `GA4_SERVICE_ACCOUNT_JSON` | 전체 | GitHub는 GA 리포트와 SEO Sheets 적재가, Vercel은 관리자 대시보드 활성 사용자 그래프가 동작하지 않는다(연결 없음으로 표시) | `.github/workflows/daily-ga-report.yml`, `.github/workflows/weekly-ga-report.yml`, `.github/workflows/seo-monitor.yml`, `apps/web/src/modules/ga/config.ts` |
 | `GITHUB_DISPATCH_REPOSITORY` (선택) | 전체 | 없으면 guesung/Web-Memo로 동작한다 | `apps/web/src/modules/slack/config.ts` |
 | `GITHUB_DISPATCH_TOKEN` | 전체 | Slack에서 release.yml과 versions.yml을 실행하지 못한다 | `apps/web/src/modules/slack/config.ts` |
 | `NEXT_PUBLIC_CHANNEL_TALK_PLUGIN_KEY` | 전체 | 채널톡 위젯이 뜨지 않는다 | `apps/web/src/components/ChannelTalk/index.tsx` |
@@ -430,6 +431,13 @@ Protocol로 직접 이벤트를 보내는 현재 구조상 이미 번들에 인
 GA4 콘솔 → 관리 → 속성 설정 상단의 **숫자** 속성 ID이며,
 `packages/shared/src/constants/Analytics.ts`의 `G-6HHNP7KJM5`는 측정 ID라 Data API에 넣으면 403/404가 납니다.
 
+`GA_SHEET_ID`는 GA·SEO 장기 이력을 같이 쌓는 Google Sheets URL의 `/d/`와 `/edit`
+사이 ID입니다. 스프레드시트를 `GA4_SERVICE_ACCOUNT_JSON`의 `client_email`에 편집자로
+공유하고, 해당 서비스 계정의 GCP 프로젝트에서 Google Sheets API를 켜야 합니다.
+탭은 없으면 스크립트가 만듭니다. 동일한 실행 ID와 시도 번호로 적재를 재시도하면
+기존 행을 갱신하고, GitHub Actions에서 재실행하여 시도 번호가 바뀌면 새 행을 남깁니다.
+값이 없으면 원본 Actions 아티팩트는 남기고 Sheets 적재만 건너뜁니다.
+
 ### `SENTRY_AUTH_TOKEN`은 확장과 웹이 서로 다른 경로로 받습니다
 
 같은 이름이지만 공급처가 둘로 갈립니다.
diff --git a/package.json b/package.json
index be025c7bf..e20e7ce85 100644
--- a/package.json
+++ b/package.json
@@ -19,6 +19,7 @@
 	"knip": "knip",
 		"seo:check": "node .github/scripts/check-seo.mjs",
 		"seo:gsc": "node .github/scripts/check-gsc.mjs",
+		"seo:sheets": "node .github/scripts/persist-seo-sheets.mjs",
 		"dev": "turbo watch dev --filter !@web-memo/app",
 		"dev-server": "pnpm -F hmr ready && pnpm -F hmr dev",
 		"dev:web": "turbo watch dev --filter @web-memo/web",