diff --git a/containers/api-proxy/otel.js b/containers/api-proxy/otel.js
index 05de05c50..286cce7b2 100644
--- a/containers/api-proxy/otel.js
+++ b/containers/api-proxy/otel.js
@@ -445,21 +445,21 @@ function setTokenAttributes(span, { provider, model, normalizedUsage, streaming
       span.setAttribute('gen_ai.response.model', model);
     }
     span.setAttributes({
-      // Standard GenAI semconv (Sentry recognizes these)
+      // Standard GenAI semconv (Sentry recognizes these as numeric)
       'gen_ai.usage.input_tokens':      normalizedUsage.input_tokens,
       'gen_ai.usage.output_tokens':     normalizedUsage.output_tokens,
       'gen_ai.request.stream':          streaming,
-      // Cache and reasoning — use Sentry measurement naming (no dots, _count suffix)
-      'cache_read_tokens_count':        normalizedUsage.cache_read_tokens,
-      'cache_write_tokens_count':       normalizedUsage.cache_write_tokens,
-      'reasoning_tokens_count':         normalizedUsage.reasoning_tokens || 0,
+      // Cache and reasoning as strings (Sentry drops unknown numeric attrs but keeps strings)
+      'awf.cache_read_tokens':          String(normalizedUsage.cache_read_tokens),
+      'awf.cache_write_tokens':         String(normalizedUsage.cache_write_tokens),
+      'awf.reasoning_tokens':           String(normalizedUsage.reasoning_tokens || 0),
     });
     span.addEvent('gen_ai.usage', {
       'gen_ai.usage.input_tokens':      normalizedUsage.input_tokens,
       'gen_ai.usage.output_tokens':     normalizedUsage.output_tokens,
-      'cache_read_tokens_count':        normalizedUsage.cache_read_tokens,
-      'cache_write_tokens_count':       normalizedUsage.cache_write_tokens,
-      'reasoning_tokens_count':         normalizedUsage.reasoning_tokens || 0,
+      'awf.cache_read_tokens':          String(normalizedUsage.cache_read_tokens),
+      'awf.cache_write_tokens':         String(normalizedUsage.cache_write_tokens),
+      'awf.reasoning_tokens':           String(normalizedUsage.reasoning_tokens || 0),
     });
   } catch { /* best-effort */ }
 }
diff --git a/containers/api-proxy/otel.test.js b/containers/api-proxy/otel.test.js
index 0d6396703..8d655eccb 100644
--- a/containers/api-proxy/otel.test.js
+++ b/containers/api-proxy/otel.test.js
@@ -235,16 +235,16 @@ describe('otel — setTokenAttributes', () => {
     expect(s.attributes['gen_ai.response.model']).toBe('gpt-4o');
     expect(s.attributes['gen_ai.usage.input_tokens']).toBe(1000);
     expect(s.attributes['gen_ai.usage.output_tokens']).toBe(500);
-    expect(s.attributes['cache_read_tokens_count']).toBe(200);
-    expect(s.attributes['cache_write_tokens_count']).toBe(50);
+    expect(s.attributes['awf.cache_read_tokens']).toBe('200');
+    expect(s.attributes['awf.cache_write_tokens']).toBe('50');
     expect(s.attributes['gen_ai.request.stream']).toBe(false);
 
     const usageEvent = s.events.find(e => e.name === 'gen_ai.usage');
     expect(usageEvent).toBeDefined();
     expect(usageEvent.attributes['gen_ai.usage.input_tokens']).toBe(1000);
     expect(usageEvent.attributes['gen_ai.usage.output_tokens']).toBe(500);
-    expect(usageEvent.attributes['cache_read_tokens_count']).toBe(200);
-    expect(usageEvent.attributes['cache_write_tokens_count']).toBe(50);
+    expect(usageEvent.attributes['awf.cache_read_tokens']).toBe('200');
+    expect(usageEvent.attributes['awf.cache_write_tokens']).toBe('50');
   });
 
   test('does not set gen_ai.response.model when model is "unknown"', async () => {