[I ɴ ᴄ ʀ ᴇ ᴅ ɪ ʙ ʟ E]

Every such website claiming to offer such heavily discounted pricing is doing prompt injections and model mixing.
I lost $2k trying to buy discounted Opus 5. Not even a single one of them will offer a direct/clean api without injections.

This is what inspection revealed.

Code

Economics: For some Sonnet queries, they are adding charges for hidden cached context. A short query incurred charges for 10 input + 287 cache-write + 3809 cache-read tokens three times; the actual cost was $0.002264 instead of the expected $0.000045—roughly 50 times more expensive. The tested Opus query did not trigger caching, and the charge matched standard rates. Caching is not applied to all queries but depends on the query type.
Conclusion: Text, tools, images, and long-context capabilities are functional. The main risks are the unconfirmed fingerprint and Sonnet's unpredictable costs due to paid hidden caching.

Before actually buying, test out their API with the inspection tools and script. good luck