Convert text to upper, lower, title or camel case (JSON body)

Text in upper, lower, title, sentence, camel, pascal, snake, kebab and constant case. No account or API key. Without PAYMENT-SIGNATURE the response is HTTP 402 with an x402 v2 payment challenge; pay and resend the identical request. Input as query string (GET) or JSON body (POST), max 64 KB; the payment is bound to the exact input. Paid calls are counted as usage of the tool on yruz.one/toolkit. Price: 0.002 USDC per call.