Anthropic released Claude Opus 5.5 on September 22. Anthropic says it performs at the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus 5. List prices are $4 per million input tokens and $20 per million output tokens, with cache reads at $0.20 per million. It is available on the Claude Platform, Amazon Web Services, Google Cloud, and Microsoft Azure as `claude-opus-5-5`, and it can be used with zero data retention. Cost has been the main reason teams kept agents on short leashes. At these prices, an agent that works through a full contract set, a support queue, or a quarter of invoices overnight fits an ordinary budget, so expect requests to use it. The data questions stay the same at any price. Before company or customer information goes in, someone should know where prompts and outputs are stored and whether the account actually has zero data retention switched on. Check whether your Anthropic account has zero data retention before approving Opus 5.5 for real data.