fix(notifier): gate missing-config warnings on AO_QUIET_STARTUP

Warnings were removed unconditionally, so misconfigured notifiers
silently became no-ops for all callers. Now warnings only suppress
during ao start (AO_QUIET_STARTUP=1); SDK consumers, tests, and other
CLI commands still receive diagnostic feedback.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/plugins/notifier-slack/src/index.test.ts

@@ -59,10 +59,18 @@ describe("notifier-slack", () => {
       expect(notifier.name).toBe("slack");
     });
 
-    it("is silent when no webhookUrl configured (no-op notifier)", () => {
+    it("warns when no webhookUrl configured", () => {
+      const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+      create();
+      expect(warnSpy).toHaveBeenCalledWith(expect.stringContaining("No webhookUrl configured"));
+    });
+
+    it("is silent when no webhookUrl configured and AO_QUIET_STARTUP is set", () => {
+      process.env.AO_QUIET_STARTUP = "1";
       const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
       create();
       expect(warnSpy).not.toHaveBeenCalled();
+      delete process.env.AO_QUIET_STARTUP;
     });
 
     it("throws on invalid URL scheme", () => {

packages/plugins/notifier-slack/src/index.ts

@@ -357,7 +357,11 @@ export function create(config?: Record<string, unknown>): Notifier {
   const defaultChannel = config?.channel as string | undefined;
   const username = (config?.username as string) ?? "Agent Orchestrator";
 
-  if (webhookUrl) {
+  if (!webhookUrl) {
+    if (!process.env.AO_QUIET_STARTUP) {
+      console.warn("[notifier-slack] No webhookUrl configured — notifications will be no-ops");
+    }
+  } else {
     validateUrl(webhookUrl, "notifier-slack");
   }
 

packages/plugins/notifier-webhook/src/index.test.ts

@@ -39,10 +39,18 @@ describe("notifier-webhook", () => {
       expect(notifier.name).toBe("webhook");
     });
 
-    it("is silent when no url configured (no-op notifier)", () => {
+    it("warns when no url configured", () => {
+      const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
+      create();
+      expect(warnSpy).toHaveBeenCalledWith(expect.stringContaining("No url configured"));
+    });
+
+    it("is silent when no url configured and AO_QUIET_STARTUP is set", () => {
+      process.env.AO_QUIET_STARTUP = "1";
       const warnSpy = vi.spyOn(console, "warn").mockImplementation(() => {});
       create();
       expect(warnSpy).not.toHaveBeenCalled();
+      delete process.env.AO_QUIET_STARTUP;
     });
 
     it("throws on invalid URL scheme", () => {

packages/plugins/notifier-webhook/src/index.ts

@@ -107,7 +107,11 @@ export function create(config?: Record<string, unknown>): Notifier {
   }
   const { retries, retryDelayMs } = normalizeRetryConfig(config);
 
-  if (url) {
+  if (!url) {
+    if (!process.env.AO_QUIET_STARTUP) {
+      console.warn("[notifier-webhook] No url configured — notifications will be no-ops");
+    }
+  } else {
     validateUrl(url, "notifier-webhook");
   }