feat: downgrade node version to 18

Author: chenanran555

.changeset/sdk-node-engines-floor.md

@@ -0,0 +1,7 @@
+---
+"@openagentpack/sdk": patch
+---
+
+Lower the SDK `engines` floor from Node `>=22` to `>=18.17.0`.
+
+The SDK runtime only relies on APIs available since Node 18.17 (`node:fs`/`path`/`crypto`/`os`, global `fetch`/`FormData`, `structuredClone`, web streams), so the previous floor was a repository baseline rather than a runtime requirement. The tsup build target is pinned to `es2022` so emitted syntax stays parseable on the new floor, and CI now runs an SDK-only packed-install smoke on Node 18 and 20 (`smoke-packed.ts --sdk-only`) to enforce the contract. The `@openagentpack/cli` and `@openagentpack/playground` packages keep their Node `>=22` requirement.

.github/workflows/ci.yml

@@ -52,12 +52,23 @@ jobs:
         run: bun scripts/verify.ts full --step "${{ matrix.step }}"
 
   package-compatibility:
-    name: Package compatibility / Node ${{ matrix.node }}
+    name: Package compatibility / Node ${{ matrix.node }}${{ matrix.scope == 'sdk' && ' (sdk-only)' || '' }}
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
-        node: [22, 24]
+        include:
+          # Full consumer smoke (sdk + playground + cli) on the repo baseline.
+          - node: 22
+            scope: all
+          - node: 24
+            scope: all
+          # SDK-only smoke on the sdk engines floor (>=18.17.0): cli/playground
+          # require Node >=22, so only the sdk tarball is installed and imported.
+          - node: 18
+            scope: sdk
+          - node: 20
+            scope: sdk
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
       - uses: oven-sh/setup-bun@0c5077e51419868618aeaa5fe8019c62421857d6 # v2
@@ -69,7 +80,10 @@ jobs:
           package-manager-cache: false
       - run: bun install --frozen-lockfile
       - run: bun scripts/verify.ts release --step build-packages
-      - run: bun scripts/verify.ts release --step package-smoke
+      - if: matrix.scope == 'all'
+        run: bun scripts/verify.ts release --step package-smoke
+      - if: matrix.scope == 'sdk'
+        run: bun scripts/release/smoke-packed.ts --sdk-only
 
   gate:
     name: Gate

packages/sdk/package.json

@@ -20,7 +20,7 @@
 		"url": "https://github.com/modelstudioai/OpenAgentPack/issues"
 	},
 	"engines": {
-		"node": ">=22"
+		"node": ">=18.17.0"
 	},
 	"type": "module",
 	"main": "./dist/index.js",

packages/sdk/tsup.config.ts

@@ -15,5 +15,7 @@ export default defineConfig({
 		},
 	},
 	clean: true,
-	target: "esnext",
+	// Keep the emitted syntax parseable by Node 18.17 (the package's engines
+	// floor): esnext would let future syntax (e.g. `using`) leak into dist.
+	target: "es2022",
 });

scripts/open-source.test.ts

@@ -53,11 +53,16 @@ describe("open-source repository invariants", () => {
 	});
 
 	test("public packages require a maintained Node.js baseline", () => {
-		for (const pkg of ["sdk", "playground", "cli"]) {
+		const nodeBaselines: Record<string, string> = {
+			sdk: ">=18.17.0",
+			playground: ">=22",
+			cli: ">=22",
+		};
+		for (const [pkg, expectedNodeRange] of Object.entries(nodeBaselines)) {
 			const manifest = JSON.parse(readFileSync(resolve(root, `packages/${pkg}/package.json`), "utf8")) as {
 				engines?: { node?: string };
 			};
-			expect(manifest.engines?.node).toBe(">=22");
+			expect(manifest.engines?.node).toBe(expectedNodeRange);
 		}
 	});
 

scripts/release/smoke-packed.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, test } from "bun:test";
-import { packedFilename } from "./smoke-packed.ts";
+import { isSdkOnly, packedFilename, smokePackages } from "./smoke-packed.ts";
 
 describe("npm pack output", () => {
 	test("accepts the npm 10 and 11 array format", () => {
@@ -14,3 +14,19 @@ describe("npm pack output", () => {
 		expect(() => packedFilename("[]", "sdk")).toThrow("Unexpected npm pack output for sdk");
 	});
 });
+
+describe("--sdk-only mode", () => {
+	test("detects the flag among CLI arguments", () => {
+		expect(isSdkOnly(["--sdk-only"])).toBe(true);
+		expect(isSdkOnly([])).toBe(false);
+		expect(isSdkOnly(["--verbose"])).toBe(false);
+	});
+
+	test("restricts the package set to sdk when enabled", () => {
+		expect(smokePackages(true)).toEqual(["sdk"]);
+	});
+
+	test("keeps the full package set when disabled", () => {
+		expect(smokePackages(false)).toEqual(["sdk", "playground", "cli"]);
+	});
+});

scripts/release/smoke-packed.ts

@@ -1,6 +1,11 @@
 /**
  * Pack the exact publish manifests, install them as an external npm consumer,
  * then exercise every public SDK entry point plus the CLI and Playground bins.
+ *
+ * `--sdk-only` restricts the run to the SDK package: pack/install only the sdk
+ * tarball (still with --engine-strict) and execute the SDK entry-point imports.
+ * This is the mode CI uses on Node versions below the cli/playground engines
+ * floor (>=22) to enforce the SDK's own >=18.17.0 engines contract.
  */
 
 import { mkdirSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
@@ -18,6 +23,14 @@ import {
 
 const root = resolve(import.meta.dirname, "../..");
 
+export function isSdkOnly(argv: readonly string[]): boolean {
+	return argv.includes("--sdk-only");
+}
+
+export function smokePackages(sdkOnly: boolean): readonly (typeof PACKAGES)[number][] {
+	return sdkOnly ? PACKAGES.filter((pkg) => pkg === "sdk") : PACKAGES;
+}
+
 type PackedPackage = { filename: string };
 
 export function packedFilename(raw: string, pkg: string): string {
@@ -33,9 +46,9 @@ function run(command: string[], cwd: string, stdout: "inherit" | "pipe" = "inher
 	return stdout === "pipe" ? (result.stdout?.toString().trim() ?? "") : "";
 }
 
-function packPackages(destination: string): string[] {
+function packPackages(destination: string, packages: readonly (typeof PACKAGES)[number][]): string[] {
 	const versions = workspaceVersions();
-	return PACKAGES.map((pkg) => {
+	return packages.map((pkg) => {
 		const pkgDir = join(root, "packages", pkg);
 		let originalLicense: string | undefined;
 		let originalManifest: string | undefined;
@@ -104,6 +117,8 @@ async function smokePlayground(consumer: string): Promise<void> {
 }
 
 async function main(): Promise<void> {
+	const sdkOnly = isSdkOnly(process.argv.slice(2));
+	const packages = smokePackages(sdkOnly);
 	const temporaryRoot = mkdtempSync(join(tmpdir(), "openagentpack-consumer-"));
 	try {
 		const tarballsDir = join(temporaryRoot, "tarballs");
@@ -112,7 +127,7 @@ async function main(): Promise<void> {
 		mkdirSync(consumer);
 		writeFileSync(join(consumer, "package.json"), '{"name":"agents-package-smoke","private":true,"type":"module"}\n');
 
-		const tarballs = packPackages(tarballsDir);
+		const tarballs = packPackages(tarballsDir, packages);
 		run(
 			[
 				"npm",
@@ -126,7 +141,7 @@ async function main(): Promise<void> {
 			],
 			consumer,
 		);
-		for (const pkg of PACKAGES) {
+		for (const pkg of packages) {
 			const license = readFileSync(join(consumer, `node_modules/@openagentpack/${pkg}/LICENSE`), "utf8");
 			if (license !== readFileSync(join(root, "LICENSE"), "utf8")) {
 				throw new Error(`${pkg} package is missing the repository license`);
@@ -143,21 +158,23 @@ async function main(): Promise<void> {
 			consumer,
 		);
 
-		const expectedVersion = JSON.parse(readFileSync(join(root, "packages/cli/package.json"), "utf8")) as {
-			version: string;
-		};
-		const cliVersion = run(
-			["node", join(consumer, "node_modules/@openagentpack/cli/dist/bin/agents.js"), "--version"],
-			consumer,
-			"pipe",
-		);
-		if (cliVersion !== expectedVersion.version) {
-			throw new Error(`Packed CLI version mismatch: expected ${expectedVersion.version}, received ${cliVersion}`);
-		}
+		if (!sdkOnly) {
+			const expectedVersion = JSON.parse(readFileSync(join(root, "packages/cli/package.json"), "utf8")) as {
+				version: string;
+			};
+			const cliVersion = run(
+				["node", join(consumer, "node_modules/@openagentpack/cli/dist/bin/agents.js"), "--version"],
+				consumer,
+				"pipe",
+			);
+			if (cliVersion !== expectedVersion.version) {
+				throw new Error(`Packed CLI version mismatch: expected ${expectedVersion.version}, received ${cliVersion}`);
+			}
 
-		await smokePlayground(consumer);
+			await smokePlayground(consumer);
+		}
 		const nodeVersion = run(["node", "--version"], consumer, "pipe");
-		console.log(`✓ Packed packages install and run under ${nodeVersion}`);
+		console.log(`✓ Packed ${sdkOnly ? "SDK package installs" : "packages install"} and run under ${nodeVersion}`);
 	} finally {
 		rmSync(temporaryRoot, { recursive: true, force: true });
 	}