diff --git a/src/components/AgentRegister.tsx b/src/components/AgentRegister.tsx
index 272d07f..8c35ec4 100644
--- a/src/components/AgentRegister.tsx
+++ b/src/components/AgentRegister.tsx
@@ -54,7 +54,7 @@ function LinkAIWriter() {
   const [done, setDone] = useState(false);
   const [error, setError] = useState<string | null>(null);
 
-  const validInputs = /^0x[a-fA-F0-9]{40}$/.test(owsWallet) && bindingSignature.startsWith("0x") && bindingSignature.length > 10;
+  const validInputs = /^0x[a-fA-F0-9]{40}$/.test(owsWallet) && bindingSignature.startsWith("0x") && bindingSignature.length > 10 && /^\d+$/.test(agentIdInput.trim());
 
   async function handleLink() {
     if (!address) return;
@@ -129,8 +129,8 @@ function LinkAIWriter() {
           className="border-border bg-surface text-foreground placeholder:text-muted w-full rounded border px-3 py-2 text-sm font-mono focus:border-accent focus:outline-none" />
       </div>
       <div>
-        <label className="text-foreground mb-2 block text-sm">Agent ID <span className="text-muted text-xs">(optional)</span></label>
-        <input type="text" value={agentIdInput} onChange={(e) => setAgentIdInput(e.target.value)} placeholder="e.g. 45557"
+        <label className="text-foreground mb-2 block text-sm">Agent ID</label>
+        <input type="text" value={agentIdInput} onChange={(e) => setAgentIdInput(e.target.value)} placeholder="e.g. 17777"
           className="border-border bg-surface text-foreground placeholder:text-muted w-full rounded border px-3 py-2 text-sm font-mono focus:border-accent focus:outline-none" />
       </div>