diff --git a/integrations/hol-guard/index.mjs b/integrations/hol-guard/index.mjs
new file mode 100644
index 0000000..4be3ca5
--- /dev/null
+++ b/integrations/hol-guard/index.mjs
@@ -0,0 +1,128 @@
+import { spawn } from "node:child_process";
+
+const DEFAULT_TIMEOUT_MS = 6000;
+
+function nonEmptyString(value) {
+	return typeof value === "string" && value.trim() ? value.trim() : undefined;
+}
+
+function guardReason(payload) {
+	for (const value of [
+		payload?.classification?.reason,
+		payload?.reason,
+		payload?.message,
+	]) {
+		const text = nonEmptyString(value);
+		if (text) return text;
+	}
+	return "HOL Guard did not allow this command.";
+}
+
+export function guardResponseToHookResult(payload) {
+	if (!payload || typeof payload !== "object") {
+		return { action: "block", reason: "HOL Guard returned an invalid response." };
+	}
+
+	const minimumAction = nonEmptyString(payload.minimum_action)?.toLowerCase();
+	const explicitlyBenign = payload?.classification?.explicitly_benign === true;
+	if (minimumAction === "allow" && explicitlyBenign) {
+		return { action: "allow" };
+	}
+	if (["allow", "monitor", "review", "block"].includes(minimumAction)) {
+		return { action: "block", reason: guardReason(payload) };
+	}
+
+	return { action: "block", reason: "HOL Guard returned no recognized decision." };
+}
+
+function guardJsonObject(stdout) {
+	const output = stdout.trim();
+	if (!output) return null;
+	try {
+		const value = JSON.parse(output);
+		if (value && typeof value === "object" && !Array.isArray(value)) return value;
+	} catch {
+		// Fall back to a final standalone JSON line for wrappers that add diagnostics.
+	}
+
+	const lines = output.split(/\r?\n/).map((line) => line.trim()).filter(Boolean);
+	for (let i = lines.length - 1; i >= 0; i--) {
+		try {
+			const value = JSON.parse(lines[i]);
+			if (value && typeof value === "object" && !Array.isArray(value)) return value;
+		} catch {
+			// Continue scanning in case HOL Guard emitted a diagnostic line first.
+		}
+	}
+	return null;
+}
+
+function guardArgs(command) {
+	return ["command", "test", command, "--json"];
+}
+
+export async function evaluateWithGuard(ctx, config = {}) {
+	if (ctx?.tool !== "cli") return { action: "allow" };
+	const command = nonEmptyString(ctx?.args?.command);
+	if (!command) return { action: "allow" };
+
+	const binary = nonEmptyString(config.binary) || process.env.HOL_GUARD_BIN || "hol-guard";
+	const configuredTimeout = Number(config.timeout_ms);
+	const timeoutMs = Number.isFinite(configuredTimeout) && configuredTimeout > 0
+		? configuredTimeout
+		: DEFAULT_TIMEOUT_MS;
+	const workspace = nonEmptyString(config.workspace) || process.cwd();
+	const childEnv = { ...process.env };
+	const guardHome = nonEmptyString(config.guard_home);
+	if (guardHome) childEnv.HOL_GUARD_HOME = guardHome;
+	const home = nonEmptyString(config.home);
+	if (home) childEnv.HOME = home;
+
+	return new Promise((resolve) => {
+		let stdout = "";
+		let stderr = "";
+		let settled = false;
+		const child = spawn(binary, guardArgs(command), {
+			stdio: ["ignore", "pipe", "pipe"],
+			env: childEnv,
+			cwd: workspace,
+			shell: false,
+		});
+
+		const finish = (result) => {
+			if (settled) return;
+			settled = true;
+			clearTimeout(timer);
+			resolve(result);
+		};
+
+		const timer = setTimeout(() => {
+			child.kill("SIGTERM");
+			finish({
+				action: "block",
+				reason: `HOL Guard did not return a decision within ${timeoutMs}ms.`,
+			});
+		}, timeoutMs);
+
+		child.stdout.on("data", (chunk) => { stdout += chunk.toString("utf-8"); });
+		child.stderr.on("data", (chunk) => { stderr += chunk.toString("utf-8"); });
+		child.on("error", (error) => {
+			finish({ action: "block", reason: `HOL Guard could not start: ${error.message}` });
+		});
+		child.on("close", (code) => {
+			if (settled) return;
+			if (code !== 0) {
+				finish({
+					action: "block",
+					reason: nonEmptyString(stderr) || `HOL Guard exited with code ${code}.`,
+				});
+				return;
+			}
+			finish(guardResponseToHookResult(guardJsonObject(stdout)));
+		});
+	});
+}
+
+export async function register(api) {
+	api.registerHook("pre_tool_use", async (ctx) => evaluateWithGuard(ctx, api.config));
+}
diff --git a/integrations/hol-guard/plugin.yaml b/integrations/hol-guard/plugin.yaml
new file mode 100644
index 0000000..f820e66
--- /dev/null
+++ b/integrations/hol-guard/plugin.yaml
@@ -0,0 +1,30 @@
+id: hol-guard
+name: HOL Guard
+version: 0.1.0
+description: Gate GitAgent CLI tool calls through HOL Guard before execution
+author: Hashgraph Online
+license: MIT
+engine: ">=2.2.0"
+entry: index.mjs
+
+config:
+  properties:
+    binary:
+      type: string
+      description: HOL Guard executable to invoke
+      env: HOL_GUARD_BIN
+      default: hol-guard
+    guard_home:
+      type: string
+      description: Optional HOL Guard state directory
+      env: HOL_GUARD_HOME
+    home:
+      type: string
+      description: Optional home directory passed to HOL Guard
+    workspace:
+      type: string
+      description: Workspace path evaluated by HOL Guard
+    timeout_ms:
+      type: number
+      description: Maximum time to wait for a Guard decision
+      default: 6000
diff --git a/test/hol-guard-integration.test.ts b/test/hol-guard-integration.test.ts
new file mode 100644
index 0000000..6e87343
--- /dev/null
+++ b/test/hol-guard-integration.test.ts
@@ -0,0 +1,90 @@
+import { chmod, mkdtemp, readFile, writeFile } from "fs/promises";
+import { tmpdir } from "os";
+import { join } from "path";
+import { describe, it } from "node:test";
+import assert from "node:assert/strict";
+import { evaluateWithGuard, guardResponseToHookResult } from "../integrations/hol-guard/index.mjs";
+
+describe("HOL Guard GitAgent integration", () => {
+	it("maps Guard command floors to GitAgent hook results", () => {
+		assert.deepEqual(
+			guardResponseToHookResult({
+				minimum_action: "allow",
+				classification: { explicitly_benign: true },
+			}),
+			{ action: "allow" },
+		);
+		assert.equal(
+			guardResponseToHookResult({
+				minimum_action: "allow",
+				classification: { explicitly_benign: false },
+			}).action,
+			"block",
+		);
+		assert.equal(
+			guardResponseToHookResult({
+				minimum_action: "monitor",
+				classification: { explicitly_benign: true },
+			}).action,
+			"block",
+		);
+		assert.deepEqual(
+			guardResponseToHookResult({
+				minimum_action: "review",
+				classification: { reason: "Guard requires review" },
+			}),
+			{ action: "block", reason: "Guard requires review" },
+		);
+		assert.equal(guardResponseToHookResult({ minimum_action: "block" }).action, "block");
+		assert.equal(guardResponseToHookResult({ unexpected: true }).action, "block");
+	});
+
+	it("only gates the cli tool", async () => {
+		assert.deepEqual(
+			await evaluateWithGuard({ tool: "read", args: { path: "README.md" } }, { binary: "missing-guard" }),
+			{ action: "allow" },
+		);
+	});
+
+	it("invokes HOL Guard command inspection and blocks a review", async (t) => {
+		if (process.platform === "win32") {
+			t.skip("fixture executable uses a POSIX shebang");
+			return;
+		}
+
+		const dir = await mkdtemp(join(tmpdir(), "gitagent-hol-guard-"));
+		const capture = join(dir, "capture.json");
+		const fixture = join(dir, "hol-guard-fixture.mjs");
+		await writeFile(
+			fixture,
+			`#!/usr/bin/env node\nimport { writeFileSync } from "node:fs";\nwriteFileSync(process.env.GUARD_CAPTURE, JSON.stringify({ argv: process.argv.slice(2), cwd: process.cwd(), guardHome: process.env.HOL_GUARD_HOME, home: process.env.HOME }));\nprocess.stdout.write(JSON.stringify({ minimum_action: "review", classification: { reason: "Guard requires review" } }, null, 2) + "\\n");\n`,
+			"utf-8",
+		);
+		await chmod(fixture, 0o755);
+
+		const previous = process.env.GUARD_CAPTURE;
+		process.env.GUARD_CAPTURE = capture;
+		try {
+			const result = await evaluateWithGuard(
+				{ session_id: "session-1", tool: "cli", args: { command: "rm -rf ./build" } },
+				{
+					binary: fixture,
+					workspace: dir,
+					timeout_ms: 2000,
+					guard_home: join(dir, "guard-home"),
+					home: join(dir, "home"),
+				},
+			);
+			assert.deepEqual(result, { action: "block", reason: "Guard requires review" });
+
+			const recorded = JSON.parse(await readFile(capture, "utf-8"));
+			assert.deepEqual(recorded.argv, ["command", "test", "rm -rf ./build", "--json"]);
+			assert.equal(recorded.cwd, dir);
+			assert.equal(recorded.guardHome, join(dir, "guard-home"));
+			assert.equal(recorded.home, join(dir, "home"));
+		} finally {
+			if (previous === undefined) delete process.env.GUARD_CAPTURE;
+			else process.env.GUARD_CAPTURE = previous;
+		}
+	});
+});