diff --git a/__tests__/unit/cat/one-catalogue-check.test.ts b/__tests__/unit/cat/one-catalogue-check.test.ts
index 84125a271..5121e83c6 100644
--- a/__tests__/unit/cat/one-catalogue-check.test.ts
+++ b/__tests__/unit/cat/one-catalogue-check.test.ts
@@ -13,6 +13,8 @@
  * the thing being checked for. So the description reads from the config
  * OrangeCat actually serves from, and this pins that.
  */
+import { readFileSync } from 'node:fs';
+import { join } from 'node:path';
 import { orangecatChain } from '@/services/cat/provider-catalog';
 import { getFreeModels } from '@/config/ai-models';
 import { CONFIGURED_GROQ_MODEL_IDS } from '@/services/ai/groq-models';
@@ -45,10 +47,10 @@ describe('the chain description is read, not written', () => {
 });
 
 describe('the old per-provider probes are gone', () => {
-  const src = require('node:fs').readFileSync(
-    require('node:path').join(__dirname, '../../../src/services/cat/health-probes.ts'),
+  const src = readFileSync(
+    join(__dirname, '../../../src/services/cat/health-probes.ts'),
     'utf8'
-  ) as string;
+  );
 
   it('leaves no second implementation behind to drift', () => {
     // Adopting a shared check and leaving the copy in place is how two answers
@@ -74,3 +76,33 @@ describe('the old per-provider probes are gone', () => {
     expect(src).toContain("v.live === null ? null : v.missing");
   });
 });
+
+describe('the health probe asks for a model the chain serves', () => {
+  // This probed `llama-3.1-8b-instant` long after Groq withdrew the whole
+  // llama-3.x family — groq-models.ts names that retirement in its own
+  // comments. So the Groq health status, and `catCanAnswer` derived from it,
+  // came from asking for a decommissioned model. The OpenRouter probe directly
+  // below it carries a comment warning about exactly this drift: the fix was
+  // applied there and not here.
+  const src = readFileSync(
+    join(__dirname, '../../../src/services/cat/health-probes.ts'),
+    'utf8'
+  );
+
+  it('probes Groq with the model the platform actually offers', () => {
+    expect(src).toContain('PLATFORM_GROQ_MODEL');
+    expect(src).not.toContain("'llama-3.1-8b-instant'");
+  });
+
+  it('pins no literal model id in either provider probe', () => {
+    // A literal here is the drift itself: it keeps "passing" while chat 404s,
+    // and keeps "failing" after the registry is fixed.
+    const from = src.indexOf('export function probeGroq');
+    const to = src.indexOf('Does Groq', from);
+    const probes = src.slice(from, to);
+    expect(probes).toContain('PLATFORM_GROQ_MODEL');
+    expect(probes).toContain('DEFAULT_FREE_MODEL_ID');
+    // No quoted model-looking literal passed as the 4th probeProvider argument.
+    expect(probes).not.toMatch(/,\s*'[a-z0-9][a-z0-9._\/-]{4,}'\s*\n\s*\)/);
+  });
+});
diff --git a/src/app/api/cron/cat-health/route.ts b/src/app/api/cron/cat-health/route.ts
index 9ee3a2f6d..a9733d93b 100644
--- a/src/app/api/cron/cat-health/route.ts
+++ b/src/app/api/cron/cat-health/route.ts
@@ -8,8 +8,11 @@
  * all. Its only callers were the diagnose route and a Cat action, so the answer
  * existed only when a human thought to ask for it. This puts it on a clock.
  *
- * Costs no tokens: the catalogue checks are GET /models, and the probes are the
- * same ones the diagnose route already runs. That is what makes it schedulable.
+ * Cost, stated correctly after getting it wrong once: the catalogue checks are
+ * GET /models and cost nothing, but probeGroq and probeOpenRouter send REAL
+ * chat completions — a few tokens each, from the same free pools the check
+ * exists to protect. Cheap, not free. That is why this runs daily rather than
+ * hourly, and why the alert coalesces instead of stacking a row per run.
  */
 
 import { runCatHealthProbes } from '@/services/cat/health-probes';
diff --git a/src/services/cat/health-probes.ts b/src/services/cat/health-probes.ts
index 2a1e8c0d7..0c656661f 100644
--- a/src/services/cat/health-probes.ts
+++ b/src/services/cat/health-probes.ts
@@ -13,7 +13,7 @@
 
 import { PROVIDER_BASE_URLS } from '@/config/ai-provider-runtime';
 import { DEFAULT_FREE_MODEL_ID } from '@/config/ai-models';
-import { promptFitsGroqOnDemand } from '@/services/ai/groq';
+import { promptFitsGroqOnDemand, PLATFORM_GROQ_MODEL } from '@/services/ai/groq';
 import { checkModelRot } from './provider-catalog';
 import { webSearch, describeAttempts } from '@bitbaum/ai-kit/web';
 import { buildCatSystemPrompt } from './system-prompt';
@@ -151,11 +151,18 @@ async function probeProvider(
 }
 
 export function probeGroq(): Promise<ProbeResult> {
+  // The model the PLATFORM actually serves, for the same reason the OpenRouter
+  // probe below stopped hardcoding one. This asked for `llama-3.1-8b-instant`
+  // long after Groq withdrew the whole llama-3.x family — groq-models.ts names
+  // that retirement in its own comments — so the health probe had been asking
+  // for a decommissioned model, and `catCanAnswer` is derived from its answer.
+  // A probe pinned to something the chain does not serve tests nothing a user
+  // depends on.
   return probeProvider(
     'groq',
     'GROQ_API_KEY',
     `${PROVIDER_BASE_URLS.groq}/chat/completions`,
-    'llama-3.1-8b-instant'
+    PLATFORM_GROQ_MODEL
   );
 }