Constant forest_filecoin::rpc::error::implementation_defined_errors::UNSUPPORTED_METHOD

pub(crate) const UNSUPPORTED_METHOD: i32 = -32001;

This error indicates that the method is not supported by the current version of the Forest node. Note that it’s not the same as not found, as we are explicitly not supporting it, e.g., because it’s deprecated or Lotus is doing the same.