diff --git a/src/resources/extensions/sf/code-intelligence.ts b/src/resources/extensions/sf/code-intelligence.ts
index 0b7db4947..2a35eb69f 100644
--- a/src/resources/extensions/sf/code-intelligence.ts
+++ b/src/resources/extensions/sf/code-intelligence.ts
@@ -131,6 +131,7 @@ interface SiftIndexWarmupOptions {
 	query?: string;
 	limit?: number;
 	retrieverTimeoutMs?: number;
+	hardTimeoutSec?: number;
 	spawnFn?: typeof spawn;
 	now?: number;
 }
@@ -140,6 +141,8 @@ const DEFAULT_SIFT_WARMUP_QUERY =
 	"repo architecture source tests entrypoints configuration";
 const DEFAULT_SIFT_WARMUP_LIMIT = 1;
 const DEFAULT_SIFT_WARMUP_RETRIEVER_TIMEOUT_MS = 30_000;
+const DEFAULT_SIFT_WARMUP_HARD_TIMEOUT_SEC = 1800;
+const SIFT_WARMUP_KILL_GRACE_SEC = 10;
 
 function readJsonConfig(configPath: string): McpConfigFile {
 	if (!existsSync(configPath)) return {};
@@ -271,6 +274,56 @@ function lookupExecutable(
 	return null;
 }
 
+interface ResolvedHardTimeout {
+	binary: string;
+	wrapperArgs: string[];
+	timeoutSec: number;
+}
+
+function resolveSiftWarmupHardTimeoutSec(
+	env: NodeJS.ProcessEnv,
+	override?: number,
+): number | null {
+	if (env.SF_SIFT_HARD_TIMEOUT_DISABLE === "1") return null;
+	if (override !== undefined) {
+		return Number.isFinite(override) && override > 0
+			? Math.floor(override)
+			: null;
+	}
+	const raw = env.SF_SIFT_HARD_TIMEOUT_SEC?.trim();
+	if (raw) {
+		const parsed = Number.parseInt(raw, 10);
+		if (parsed === 0) return null;
+		if (Number.isFinite(parsed) && parsed > 0) return parsed;
+	}
+	return DEFAULT_SIFT_WARMUP_HARD_TIMEOUT_SEC;
+}
+
+function resolveSiftWarmupTimeoutWrapper(
+	env: NodeJS.ProcessEnv,
+	timeoutSec: number,
+): ResolvedHardTimeout | null {
+	if (process.platform === "win32") return null;
+	const candidates =
+		process.platform === "darwin"
+			? ["gtimeout", "timeout"]
+			: ["timeout", "gtimeout"];
+	for (const candidate of candidates) {
+		const binary = lookupExecutable(candidate, env);
+		if (binary) {
+			return {
+				binary,
+				wrapperArgs: [
+					`--kill-after=${SIFT_WARMUP_KILL_GRACE_SEC}`,
+					String(timeoutSec),
+				],
+				timeoutSec,
+			};
+		}
+	}
+	return null;
+}
+
 export function resolveProjectRagBinary(
 	env: NodeJS.ProcessEnv = process.env,
 ): string | null {
@@ -401,7 +454,7 @@ export function ensureSiftIndexWarmup(
 		};
 	}
 
-	const args = [
+	const siftArgs = [
 		"search",
 		"--json",
 		"--strategy",
@@ -417,6 +470,24 @@ export function ensureSiftIndexWarmup(
 		options.query ?? DEFAULT_SIFT_WARMUP_QUERY,
 	];
 
+	const hardTimeoutSec = resolveSiftWarmupHardTimeoutSec(
+		env,
+		options.hardTimeoutSec,
+	);
+	const wrapper =
+		hardTimeoutSec !== null
+			? resolveSiftWarmupTimeoutWrapper(env, hardTimeoutSec)
+			: null;
+	const command = wrapper ? wrapper.binary : detection.binaryPath;
+	const args = wrapper
+		? [...wrapper.wrapperArgs, detection.binaryPath, ...siftArgs]
+		: siftArgs;
+	const startedReason = wrapper
+		? `sift page-index-hybrid warmup started (hard cap ${wrapper.timeoutSec}s via ${wrapper.binary})`
+		: hardTimeoutSec === null
+			? "sift page-index-hybrid warmup started (hard cap disabled)"
+			: "sift page-index-hybrid warmup started (no timeout(1)/gtimeout on PATH; running unbounded)";
+
 	try {
 		mkdirSync(join(projectRoot, ".sf", "runtime"), { recursive: true });
 		writeFileSync(
@@ -425,9 +496,11 @@ export function ensureSiftIndexWarmup(
 				{
 					schemaVersion: 2,
 					startedAt: new Date(now).toISOString(),
-					command: detection.binaryPath,
+					command,
 					cwd: projectRoot,
 					args,
+					siftBinary: detection.binaryPath,
+					hardTimeoutSec: wrapper?.timeoutSec ?? null,
 				},
 				null,
 				2,
@@ -435,7 +508,7 @@ export function ensureSiftIndexWarmup(
 			"utf-8",
 		);
 
-		const child = (options.spawnFn ?? spawn)(detection.binaryPath, args, {
+		const child = (options.spawnFn ?? spawn)(command, args, {
 			cwd: projectRoot,
 			env,
 			stdio: "ignore",
@@ -444,8 +517,8 @@ export function ensureSiftIndexWarmup(
 		child.unref();
 		return {
 			status: "started",
-			reason: "sift page-index-hybrid warmup started",
-			command: detection.binaryPath,
+			reason: startedReason,
+			command,
 			args,
 			markerPath,
 		};
@@ -453,7 +526,7 @@ export function ensureSiftIndexWarmup(
 		return {
 			status: "error",
 			reason: err instanceof Error ? err.message : String(err),
-			command: detection.binaryPath,
+			command,
 			args,
 			markerPath,
 		};
diff --git a/src/resources/extensions/sf/tests/code-intelligence.test.ts b/src/resources/extensions/sf/tests/code-intelligence.test.ts
index 1bc58666c..e3bc430d8 100644
--- a/src/resources/extensions/sf/tests/code-intelligence.test.ts
+++ b/src/resources/extensions/sf/tests/code-intelligence.test.ts
@@ -447,6 +447,83 @@ test("ensureSiftIndexWarmup skips recent marker and explicit non-sift backends",
 	}
 });
 
+test("ensureSiftIndexWarmup wraps sift with timeout(1) when available", () => {
+	const projectRoot = makeProject();
+	try {
+		const fakeSift = writeFakeSiftBinary(projectRoot);
+		const fakeTimeout = join(projectRoot, "bin", "timeout");
+		writeFileSync(fakeTimeout, "", "utf-8");
+
+		const calls: Array<{ command: string; args: string[] }> = [];
+		const fakeSpawn = ((command: string, args: string[]) => {
+			calls.push({ command, args });
+			return { unref() {} };
+		}) as unknown as typeof import("node:child_process").spawn;
+
+		const result = ensureSiftIndexWarmup(projectRoot, undefined, {
+			env: { PATH: join(projectRoot, "bin") },
+			spawnFn: fakeSpawn,
+			hardTimeoutSec: 42,
+			force: true,
+			now: Date.parse("2026-05-02T12:00:00.000Z"),
+		});
+
+		assert.equal(result.status, "started");
+		assert.equal(calls.length, 1);
+		assert.equal(calls[0].command, fakeTimeout);
+		assert.deepEqual(calls[0].args.slice(0, 3), [
+			"--kill-after=10",
+			"42",
+			fakeSift,
+		]);
+		assert.equal(calls[0].args[3], "search");
+		assert.match(result.reason, /hard cap 42s/);
+		const marker = JSON.parse(
+			readFileSync(
+				join(projectRoot, ".sf", "runtime", "sift-index-warmup.json"),
+				"utf-8",
+			),
+		);
+		assert.equal(marker.command, fakeTimeout);
+		assert.equal(marker.siftBinary, fakeSift);
+		assert.equal(marker.hardTimeoutSec, 42);
+	} finally {
+		cleanup(projectRoot);
+	}
+});
+
+test("ensureSiftIndexWarmup honors SF_SIFT_HARD_TIMEOUT_DISABLE", () => {
+	const projectRoot = makeProject();
+	try {
+		const fakeSift = writeFakeSiftBinary(projectRoot);
+		writeFileSync(join(projectRoot, "bin", "timeout"), "", "utf-8");
+
+		const calls: Array<{ command: string; args: string[] }> = [];
+		const fakeSpawn = ((command: string, args: string[]) => {
+			calls.push({ command, args });
+			return { unref() {} };
+		}) as unknown as typeof import("node:child_process").spawn;
+
+		const result = ensureSiftIndexWarmup(projectRoot, undefined, {
+			env: {
+				PATH: join(projectRoot, "bin"),
+				SF_SIFT_HARD_TIMEOUT_DISABLE: "1",
+			},
+			spawnFn: fakeSpawn,
+			force: true,
+			now: Date.parse("2026-05-02T12:00:00.000Z"),
+		});
+
+		assert.equal(result.status, "started");
+		assert.equal(calls.length, 1);
+		assert.equal(calls[0].command, fakeSift);
+		assert.equal(calls[0].args[0], "search");
+		assert.match(result.reason, /hard cap disabled/);
+	} finally {
+		cleanup(projectRoot);
+	}
+});
+
 test("ensureSiftIndexWarmup ignores stale absolute-path warmup markers", () => {
 	const projectRoot = makeProject();
 	try {