diff --git a/src/types/TokenMetrics.ts b/src/types/TokenMetrics.ts
index b1cb8f8..ec3c866 100644
--- a/src/types/TokenMetrics.ts
+++ b/src/types/TokenMetrics.ts
@@ -9,6 +9,7 @@ export interface TranscriptLine {
     message?: { usage?: TokenUsage };
     isSidechain?: boolean;
     timestamp?: string;
+    isApiErrorMessage?: boolean;
 }
 
 export interface TokenMetrics {
diff --git a/src/utils/jsonl.ts b/src/utils/jsonl.ts
index 617f313..6a1ec4e 100644
--- a/src/utils/jsonl.ts
+++ b/src/utils/jsonl.ts
@@ -114,7 +114,8 @@ export async function getTokenMetrics(transcriptPath: string): Promise<TokenMetr
                     cachedTokens += data.message.usage.cache_creation_input_tokens ?? 0;
 
                     // Track the most recent entry with isSidechain: false (or undefined, which defaults to main chain)
-                    if (data.isSidechain !== true && data.timestamp) {
+                    // Also skip API error messages (synthetic messages with 0 tokens)
+                    if (data.isSidechain !== true && data.timestamp && !data.isApiErrorMessage) {
                         const entryTime = new Date(data.timestamp);
                         if (!mostRecentTimestamp || entryTime > mostRecentTimestamp) {
                             mostRecentTimestamp = entryTime;