Claude cuts long-agent startup latency by 35%
Anthropic’s public-beta message threads let long-running agents send only new messages after the first turn, cutting median time to first token by about 35% for 500K to 1M-token requests. Add a thread ID to each Messages API call, and Anthropic keeps the encrypted thread in memory for five minutes after the last request instead of making the client resend everything. Token usage stays the same, but coding, computer-use, and document-heavy agents start responding faster.