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Decision facts

• Claude Fable 5.1 is #3; Gemma 4 31B is #27 on the same current language board.
• Index scores are 87.7 for Claude Fable 5.1 and 69.7 for Gemma 4 31B. Their published uncertainty intervals do not overlap, but the aggregate Index does not predict performance on every task; compare the relevant benchmark configurations before choosing.
• Both positions use Measured evidence.
• Listed output price per 1M tokens is $50.00 for Claude Fable 5.1 and $0.34 for Gemma 4 31B. For 1,000 requests with 2,000 input and 500 output tokens each (2M input + 0.5M output), the listed-rate estimate is $45.00 for Claude Fable 5.1 versus $0.35 for Gemma 4 31B. Gemma 4 31B costs 99.2% less in this scenario. This excludes caching, batch discounts, prompt-length tiers, tool charges and retries; verify the selected endpoint before budgeting.
• Published context is 1,000,000 tokens for Claude Fable 5.1 and 262,144 for Gemma 4 31B.
• Weight access differs: Claude Fable 5.1 is none; Gemma 4 31B is open.
• ModelCap currently lists 4 providers for Claude Fable 5.1 and 13 for Gemma 4 31B.

These are separate published fields, not a synthetic winner. ModelCap does not collapse price, access, context, and capability evidence into a hidden recommendation score.