Claude Fable 5.1 made me a nice animated pelican

Claude Fable 5.1 replaced Fable 5 on September 1, 2026. While input and output prices remain at 10 and 50 dollars per million tokens, cache read costs decreased from 1 dollar to 0.25 dollars per million tokens. Anthropic reports improved performance across all benchmarks. Fable 5 remains available until at least June 9, 2027. Users must determine if the performance gains justify the migration costs for their specific workloads based on compatibility and pricing specifications.