With 2.5 pro I get following message:
AI service error: 402 This request requires more credits, or fewer max_tokens. You requested up to 65536 tokens, but can only afford 3267. To increase, visit https://openrouter.ai/settings/credits and upgrade to a paid account Try again
I asked gemini about my limits and API usage, it tells me that I can use the API but there are some limits
Maybe shakespeare is requesting too much at once? can you set this lower ?

