The original headline is "Claude Opus 5 vs Fable 5: Which Tier Earns the Money"

Short summary

Claude Opus 5 launched at Opus 4.8's price point ($5/$25 per million tokens), closing most of the performance gap with Fable 5 at half the cost. Migration from 4.8 is not a simple model swap: thinking is now on by default, disabling thinking above high effort throws a 400, and rate limits are in a separate bucket. Prompt caching floor dropped to 512 tokens, and new cybersecurity safeguards can silently refuse requests with empty content arrays.

• •Opus 5 matches Opus 4.8 pricing at $5/$25 per M tokens, half of Fable 5's $10/$50
• •Thinking-on-by-default and disabled-thinking caps require code audits before migration
• •Prompt caching floor halved to 512 tokens; cybersecurity refusals return empty content arrays

Generated with AI, which can make mistakes.