The official model identifier for Claude Sonnet 5.5 is claude-sonnet-5-5. Anthropic presents it as suitable for clearly scoped everyday tasks, coding, and document work.
This is the vendor’s product positioning. Actual adoption should consider task-specific evaluations and tool settings. Even with the same model name, the effort setting and service configuration can affect results.
Announced: September 28, 2026. Reviewed: October 3, 2026 UTC. This document does not include independent performance testing.