Microsoft's partnership with Anthropic allows Claude Sonnet 4.6, Opus 4.7, and Opus 4.8 to be used directly inside Copilot Studio as a generative model. Claude Opus 4.8 (released May 28, 2026) is the latest flagship with a full 1M token context window and improved coding accuracy, priced at $5/$25 per MTok. This is critical for enterprise customers who find Claude's instruction-following (e.g. for strict JSON schema output) to be superior for specific high-stakes automation. Claude acts as a peer to GPT models, and can be toggled per-environment in the Power Platform Admin Center (PPAC).
Claude is particularly favored for 'Deep Context' RAG because of its massive context window — Opus 4.7 introduced 200K–1M tokens (beta), and Opus 4.8 now delivers 1M tokens as standard with improved coding accuracy. Claude's record-breaking performance in Needle In A Haystack retrieval tests — 98.5% visual acuity benchmark — makes it ideal for enterprise use. When an agent needs to analyze a 1,000-page regulatory manual, Claude Opus 4.8 is now the preferred reasoning engine.