gtnloncexswap docs:
This nifty API triangulates the approximate price of GNTL based on the liquidity of other coins (SOL, DOGE, and USDC) in cexswap without relying on trading volume on professional services.

Docs:
GET /now -> Returns the current approximated GNTL price (updated hourly)
GET /history -> Returns 7 day history in format [[price,utc_string_timestamp]] (updated hourly)

There is no rate limit, but you should keep your requests to 1 per hour as this API only updates it's data once an hour.