I’ve been seeing the occasional API error and connection reset like many others, but I noticed something today that made me curious. While working in Claude Code with my Max 20x subscription, I remembered I still had the $200 API credit Anthropic gave me a while back. Since I wasn’t paying out of pocket, I decided to enable Fast Mode and see how it compared. Before switching, I had been waiting through some pretty long response times from Opus 4.8. After enabling Fast Mode, I hit two API errors initially, but once it started responding, it was smooth sailing. For the next ~90 minutes I didn’t see a single API error, responses were consistently fast, and the workflow felt noticeably smoother. Out of curiosity, I turned Fast Mode back off. The first couple of prompts were still quick, but then performance gradually degraded. API errors started appearing again, eventually followed by multiple retries and connection resets. This is obviously just one data point, so I’m not claiming causation. But it left me wondering: Does Fast Mode use different infrastructure, routing, capacity, or scheduling behind the scenes? Or was I just lucky with timing? Has anyone else compared a long coding session with Fast Mode on vs. off and noticed a similar difference? I’d be especially interested if anyone has actual measurements rather than just anecdotal impressions. submitted by /u/officialDave
Originally posted by u/officialDave on r/ClaudeCode