Cargo Features

[dependencies]
ismp-parachain-runtime-api = { version = "1.15.1", default-features = false, features = ["std"] }
default = std

The std feature is set by default whenever ismp-parachain-runtime-api is added without default-features = false somewhere in the dependency tree.

std default

Enables std of cumulus-pallet-parachain-system ^0.16.0 and sp-api

ismp-parachain-runtime-api has 2 features without comments.