feat(tess): add safe runtime observability (#726)

apps/gateway/src/agent/providers.controller.test.ts

@@ -0,0 +1,46 @@
+import { describe, expect, it, vi } from 'vitest';
+import { ProvidersController } from './providers.controller.js';
+
+describe('ProvidersController operational status', (): void => {
+  it('reports provider latency and effective policy without exposing provider error details', (): void => {
+    const providerService = {
+      getProvidersHealth: vi.fn(() => [
+        {
+          name: 'fleet',
+          status: 'down',
+          latencyMs: 42,
+          lastChecked: '2026-07-12T00:00:00.000Z',
+          modelCount: 0,
+          error: 'credential-canary=secret-value',
+        },
+      ]),
+      getEffectivePolicyStatus: vi.fn(() => ({
+        healthCheckIntervalSecs: 60,
+        configuredProviders: ['fleet'],
+        availableModelCount: 0,
+      })),
+    };
+    const controller = new ProvidersController(providerService as never, {} as never, {} as never);
+
+    const status = controller.status();
+
+    expect(status).toEqual({
+      providers: [
+        {
+          name: 'fleet',
+          status: 'down',
+          latencyMs: 42,
+          lastChecked: '2026-07-12T00:00:00.000Z',
+          modelCount: 0,
+          errorCode: 'provider_unavailable',
+        },
+      ],
+      effectivePolicy: {
+        healthCheckIntervalSecs: 60,
+        configuredProviders: ['fleet'],
+        availableModelCount: 0,
+      },
+    });
+    expect(JSON.stringify(status)).not.toContain('secret-value');
+  });
+});