bitcoin/doc/release-notes-26485.md

JSON-RPC

For RPC methods which accept options parameters ((importmulti, listunspent, fundrawtransaction, bumpfee, send, sendall, walletcreatefundedpsbt, simulaterawtransaction), it is now possible to pass the options as named parameters without the need for a nested object. (#26485)

This means it is possible make calls like:

src/bitcoin-cli -named bumpfee txid fee_rate=100

instead of

src/bitcoin-cli -named bumpfee txid options='{"fee_rate": 100}'