Amazon saves millions by replacing Sonnet 4.6 with Strands Decider

Amazon has replaced Anthropic’s Sonnet 4.6 with its in-house Strands Decider across internal agent workloads, saving the company millions of dollars, according to a company blog post. The Decider runs on Strands, Amazon’s fully assembled agent harness, which pairs an OS-contained agent sandbox with Dogwood policy enforcement and a virtual shell built for AI agents. The switch matters because it shows a major cloud provider substituting a third-party frontier model with its own routing and decision layer to cut inference costs at scale. Amazon did not disclose exact savings, token volumes or the share of workloads migrated. Watch for whether other enterprises adopt harness-level model substitution, and whether Anthropic’s pricing or Amazon’s model mix shifts in response.