diff --git a/README.md b/README.md
index 77de38e..bc5b777 100644
--- a/README.md
+++ b/README.md
@@ -75,10 +75,12 @@ await isAvailable("likely-unregistered-thing-320485230458.com"); // => true
 For quick checks, a minimal CLI is included:
 
 ```bash
-npx rdapper example.com
+npx rdapper example.com example.org
 echo "example.com" | npx rdapper
 ```
 
+Domains are looked up one at a time, in order, printing each result as JSON; the exit code is `1` when any lookup fails.
+
 ### Edge runtimes (e.g., Vercel Edge)
 
 WHOIS requires a raw TCP connection over port 43 via `node:net`, which is not available on edge runtimes. rdapper lazily loads `node:net` only when the WHOIS path is taken.
diff --git a/bin/cli.mjs b/bin/cli.mjs
index 9a24d46..c8eabd9 100755
--- a/bin/cli.mjs
+++ b/bin/cli.mjs
@@ -2,24 +2,36 @@
 
 // Quick informal command-line interface for rdapper
 // Usage:
-//   npx rdapper example.com
+//   npx rdapper example.com [example.org ...]
 //   echo "example.com" | npx rdapper
+// Exits with 1 when any lookup fails.
 
 import { createInterface } from "node:readline";
 import { lookup } from "../dist/index.mjs";
 
+/** Domains from the arguments, or else one per non-blank line of stdin. */
+async function* domains() {
+  const args = process.argv.slice(2);
+  if (args.length) {
+    yield* args;
+    return;
+  }
+  for await (const line of createInterface({ input: process.stdin })) {
+    if (line.trim()) yield line;
+  }
+}
+
 async function main() {
-  if (process.argv.length > 2) {
-    // URL(s) specified in the command arguments
-    console.log(JSON.stringify(await lookup(process.argv[process.argv.length - 1]), null, 2));
-  } else {
-    // No domain passed as argument, read from each line of stdin
-    const rlInterface = createInterface({
-      input: process.stdin,
-    });
-    rlInterface.on("line", async (line) => {
-      console.log(JSON.stringify(await lookup(line), null, 2));
-    });
+  // One at a time, so output follows input order and registries aren't flooded
+  for await (const domain of domains()) {
+    if (domain.startsWith("-")) {
+      console.error(`Unknown option: ${domain}`);
+      process.exitCode = 2;
+      return;
+    }
+    const result = await lookup(domain);
+    if (!result.ok) process.exitCode = 1;
+    console.log(JSON.stringify(result, null, 2));
   }
 }