Address comments, skip tokenization billing fallback

Author: Theodore Li

apps/sim/lib/tokenization/streaming.ts

@@ -30,6 +30,11 @@ export function processStreamingBlockLog(log: BlockLog, streamedContent: string)
     return false
   }
 
+  // Skip recalculation if cost was explicitly set by the billing layer (e.g. BYOK zero cost)
+  if (log.output?.cost?.pricing) {
+    return false
+  }
+
   // Check if we have content to tokenize
   if (!streamedContent?.trim()) {
     return false

apps/sim/providers/index.ts

@@ -58,7 +58,7 @@ const ZERO_COST = Object.freeze({
   input: 0,
   output: 0,
   total: 0,
-  pricing: Object.freeze({ input: 0, output: 0, updatedAt: '' }),
+  pricing: Object.freeze({ input: 0, output: 0, updatedAt: new Date(0).toISOString() }),
 })
 
 /**
@@ -68,7 +68,10 @@ const ZERO_COST = Object.freeze({
  */
 function zeroCostForBYOK(response: StreamingExecution): void {
   const output = response.execution?.output
-  if (!output || typeof output !== 'object') return
+  if (!output || typeof output !== 'object') {
+    logger.warn('zeroCostForBYOK: output not available at intercept time; cost may not be zeroed')
+    return
+  }
 
   Object.defineProperty(output, 'cost', {
     get: () => ZERO_COST,