Anthropic released Message Threads as a public beta on its Claude platform. Previously, every API request had to resend the entire conversation history. Message Threads transmits only what has changed since the last message.
According to Anthropic, this cuts time to first token by about 35 percent for requests between 500,000 and one million tokens. The company says coding agents, computer-use agents, and workflows that process large volumes of documents or images benefit most.
The thread stays encrypted in memory between requests and expires after five minutes of inactivity. Token usage does not change, because Claude still reads the full conversation history. The feature works on the Claude platform and through AWS, Microsoft Foundry, and Google Cloud. Details are in Anthropic's documentation.
Source: The Decoder