What I was getting at is:

    cpu: 0.2
    kw_read_s: 0.12

is describing a single 'object'. How do you describe an array or list of these objects? Something like:

    cpu: 0.2
    kw_read_s: 0.12

    cpu: 1.3
    kw_read_s: 0.4

Do you use a blank line to denote a new 'object'? In JSON it would be done this way, and this conforms to how the vast majority of command output maps (as they tend to be rows of columnar data):

    [
      {
        "cpu": 0.2,
        "kw_read_s": 0.12
      },
      {
        "cpu": 1.3,
        "kw_read_s": 0.4
      }
    ]

The other benefit to JSON here is that the formatting doesn't matter. This could also be expressed as a block of text with no spaces or newlines between elements:

    [{"cpu": 0.2,"kw_read_s": 0.12},{"cpu": 1.3,"kw_read_s": 0.4}]

Finally, this can also be streamed, using JSON Lines:

    {"cpu": 0.2, "kw_read_s": 0.12}
    {"cpu": 1.3, "kw_read_s": 0.4}

You're not wrong, but sometimes simple formats aren't as simple as they look. It sounds like what you want is basically a format like /etc/os-release:

    NAME="Rocky Linux"
    VERSION="8.5 (Green Obsidian)"
    ID="rocky"
    ID_LIKE="rhel centos fedora"
    VERSION_ID="8.5"
    PLATFORM_ID="platform:el8"
    PRETTY_NAME="Rocky Linux 8.5 (Green Obsidian)"
    ANSI_COLOR="0;32"
    CPE_NAME="cpe:/o:rocky:rocky:8.5:GA"
    HOME_URL="https://rockylinux.org/"
    BUG_REPORT_URL="https://bugs.rockylinux.org/"
    ROCKY_SUPPORT_PRODUCT="Rocky Linux"
    ROCKY_SUPPORT_PRODUCT_VERSION="8"

On the surface this seems great, but those quotation marks are kind of annoying. Is it possible there's an escape syntax that's used in case the name also includes quotes? eg VERSION="8.5 (Green \"Aqua\" Obsidian)"? Is it also possible you can embed newlines in between the quotes too? Who knows... Thankfully with JSON there is a simple spec.