shellcheck (https://www.shellcheck.net/) is a popular tool for checking Unix shell scripts for common problems, such as undefined variables. It has much to say about rad.sh: output is below. (If you’d like help fixing these things, let me know. I’ve done that a fair bit over the years.)

In rad.sh line 3:
    local op=$(echo $1 | jq '.operation')
          ^-- SC2155 (warning): Declare and assign separately to avoid masking return values.
                    ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
    local op=$(echo "$1" | jq '.operation')


In rad.sh line 10:
    local ids=$(echo $1 | jq '.ids')
          ^-^ SC2155 (warning): Declare and assign separately to avoid masking return values.
                     ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
    local ids=$(echo "$1" | jq '.ids')


In rad.sh line 11:
    local id=$(echo $ids | jq '.[0]')
          ^-- SC2155 (warning): Declare and assign separately to avoid masking return values.
                    ^--^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
    local id=$(echo "$ids" | jq '.[0]')


In rad.sh line 21:
            { out=$(rad-tui $1 select 2>&1 >&3 3>&-); } 3>&1
                            ^-- SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
            { out=$(rad-tui "$1" select 2>&1 >&3 3>&-); } 3>&1


In rad.sh line 26:
            op=$(extract_operation $out)
                                   ^--^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
            op=$(extract_operation "$out")


In rad.sh line 27:
            id=$(extract_id $out)
                            ^--^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
            id=$(extract_id "$out")


In rad.sh line 29:
            rad $1 $op $id
                ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                   ^-^ SC2086 (info): Double quote to prevent globbing and word splitting.
                       ^-^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
            rad "$1" "$op" "$id"


In rad.sh line 33:
            { out=$(rad-tui $1 select $args 2>&1 >&3 3>&-); } 3>&1
                            ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                                      ^---^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
            { out=$(rad-tui "$1" select "$args" 2>&1 >&3 3>&-); } 3>&1


In rad.sh line 34:
            id=$(extract_id $out)
                            ^--^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
            id=$(extract_id "$out")


In rad.sh line 38:
            rad $1 $2 $id ${args[@]:2}
                ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                   ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                      ^-^ SC2086 (info): Double quote to prevent globbing and word splitting.
                          ^----------^ SC2068 (error): Double quote array expansions to avoid re-splitting elements.

Did you mean: 
            rad "$1" "$2" "$id" ${args[@]:2}


In rad.sh line 41:
        rad $@
            ^-- SC2068 (error): Double quote array expansions to avoid re-splitting elements.


In rad.sh line 44:
    rad $@
        ^-- SC2068 (error): Double quote array expansions to avoid re-splitting elements.

For more information:
  https://www.shellcheck.net/wiki/SC2068 -- Double quote array expansions to ...
  https://www.shellcheck.net/wiki/SC2155 -- Declare and assign separately to ...
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...