fix(coding-agent): skip fd/rg downloads on unsupported architectures

Only x64 and arm64 map to prebuilt release archives. ARM32 and ia32 previously
fell back to x86-64 binaries; now pi warns and recommends the system package manager.

fixes #11209

packages/coding-agent/src/utils/tools-manager.ts

@@ -24,7 +24,19 @@ interface ToolConfig {
 	binaryName: string; // Name of the binary inside the archive
 	systemBinaryNames?: string[]; // Alternative system command names to try before downloading
 	tagPrefix: string; // Prefix for tags (e.g., "v" for v1.0.0, "" for 1.0.0)
-	getAssetName: (version: string, plat: string, architecture: string) => string | null;
+	getAssetName: (version: string, target: string) => string;
+}
+
+// Map Node's platform/arch to the release target suffix shared by fd and ripgrep.
+// Only x64 and arm64 are mapped. Other architectures (e.g. ARM32 `arm`, `ia32`)
+// must not fall back to x86-64 binaries (#11209).
+function getReleaseTarget(plat: string, architecture: string): string | undefined {
+	const archStr = architecture === "arm64" ? "aarch64" : architecture === "x64" ? "x86_64" : undefined;
+	if (!archStr) return undefined;
+	if (plat === "darwin") return `${archStr}-apple-darwin.tar.gz`;
+	if (plat === "linux") return `${archStr}-unknown-linux-musl.tar.gz`;
+	if (plat === "win32") return `${archStr}-pc-windows-msvc.zip`;
+	return undefined;
 }
 
 const TOOLS: Record<string, ToolConfig> = {
@@ -34,38 +46,14 @@ const TOOLS: Record<string, ToolConfig> = {
 		binaryName: "fd",
 		systemBinaryNames: ["fd", "fdfind"],
 		tagPrefix: "v",
-		getAssetName: (version, plat, architecture) => {
-			if (plat === "darwin") {
-				const archStr = architecture === "arm64" ? "aarch64" : "x86_64";
-				return `fd-v${version}-${archStr}-apple-darwin.tar.gz`;
-			} else if (plat === "linux") {
-				const archStr = architecture === "arm64" ? "aarch64" : "x86_64";
-				return `fd-v${version}-${archStr}-unknown-linux-musl.tar.gz`;
-			} else if (plat === "win32") {
-				const archStr = architecture === "arm64" ? "aarch64" : "x86_64";
-				return `fd-v${version}-${archStr}-pc-windows-msvc.zip`;
-			}
-			return null;
-		},
+		getAssetName: (version, target) => `fd-v${version}-${target}`,
 	},
 	rg: {
 		name: "ripgrep",
 		repo: "BurntSushi/ripgrep",
 		binaryName: "rg",
 		tagPrefix: "",
-		getAssetName: (version, plat, architecture) => {
-			if (plat === "darwin") {
-				const archStr = architecture === "arm64" ? "aarch64" : "x86_64";
-				return `ripgrep-${version}-${archStr}-apple-darwin.tar.gz`;
-			} else if (plat === "linux") {
-				const archStr = architecture === "arm64" ? "aarch64" : "x86_64";
-				return `ripgrep-${version}-${archStr}-unknown-linux-musl.tar.gz`;
-			} else if (plat === "win32") {
-				const archStr = architecture === "arm64" ? "aarch64" : "x86_64";
-				return `ripgrep-${version}-${archStr}-pc-windows-msvc.zip`;
-			}
-			return null;
-		},
+		getAssetName: (version, target) => `ripgrep-${version}-${target}`,
 	},
 };
 
@@ -262,16 +250,15 @@ async function downloadTool(tool: "fd" | "rg"): Promise<string> {
 
 	const plat = platform();
 	const architecture = arch();
+	const target = getReleaseTarget(plat, architecture);
+	if (!target) {
+		throw new Error(`Unsupported platform: ${plat}/${architecture}`);
+	}
 
 	// fd is pinned on darwin/x64, so skip the version lookup there.
 	const version =
 		tool === "fd" && plat === "darwin" && architecture === "x64" ? "10.3.0" : await getLatestVersion(config.repo);
-
-	// Get asset name for this platform
-	const assetName = config.getAssetName(version, plat, architecture);
-	if (!assetName) {
-		throw new Error(`Unsupported platform: ${plat}/${architecture}`);
-	}
+	const assetName = config.getAssetName(version, target);
 
 	// Create tools directory
 	mkdirSync(TOOLS_DIR, { recursive: true });
@@ -372,6 +359,15 @@ export async function ensureTool(
 		return undefined;
 	}
 
+	// Prebuilt downloads only exist for the targets mapped in getReleaseTarget.
+	if (!getReleaseTarget(platform(), arch())) {
+		onStatus?.({
+			type: "warning",
+			message: `${config.name} not found. Automatic download is not supported on ${platform()}/${arch()}. Install ${config.name} with your system package manager.`,
+		});
+		return undefined;
+	}
+
 	// Tool not found - download it
 	onStatus?.({ type: "info", message: `${config.name} not found. Downloading...` });
 

packages/coding-agent/test/tools-manager.test.ts

@@ -1,5 +1,7 @@
 import type * as ChildProcess from "node:child_process";
 import type * as Fs from "node:fs";
+import type * as Os from "node:os";
+import { arch, platform } from "os";
 import { afterEach, describe, expect, it, vi } from "vitest";
 import { ensureTool, getLatestVersion, type ToolStatus } from "../src/utils/tools-manager.ts";
 
@@ -13,6 +15,15 @@ vi.mock("fs", async (importOriginal) => {
 	};
 });
 
+vi.mock("os", async (importOriginal) => {
+	const actual = await importOriginal<typeof Os>();
+	return {
+		...actual,
+		arch: vi.fn(() => "x64"),
+		platform: vi.fn(() => "linux"),
+	};
+});
+
 vi.mock("child_process", async (importOriginal) => {
 	const actual = await importOriginal<typeof ChildProcess>();
 	return {
@@ -25,6 +36,8 @@ afterEach(() => {
 	if (originalOffline === undefined) delete process.env.PI_OFFLINE;
 	else process.env.PI_OFFLINE = originalOffline;
 	vi.unstubAllGlobals();
+	vi.mocked(arch).mockReturnValue("x64");
+	vi.mocked(platform).mockReturnValue("linux");
 });
 
 function redirectResponse(location: string): Response {
@@ -139,4 +152,24 @@ describe("ensureTool", () => {
 			},
 		]);
 	});
+
+	// #11209: ARM32 previously fell back to x86-64 release archives.
+	it.each(["arm", "ia32"])("does not download x86-64 binaries on %s", async (architecture) => {
+		delete process.env.PI_OFFLINE;
+		vi.mocked(arch).mockReturnValue(architecture as NodeJS.Architecture);
+		const fetchMock = vi.fn();
+		vi.stubGlobal("fetch", fetchMock);
+		const statuses: ToolStatus[] = [];
+
+		const result = await ensureTool("rg", (status) => statuses.push(status));
+
+		expect(result).toBeUndefined();
+		expect(fetchMock).not.toHaveBeenCalled();
+		expect(statuses).toEqual([
+			{
+				type: "warning",
+				message: `ripgrep not found. Automatic download is not supported on linux/${architecture}. Install ripgrep with your system package manager.`,
+			},
+		]);
+	});
 });