AWS - Step functions, use execution input within a TuningStep

The python SDK for step functions generates corresponding code, we need a string concatenation / format built into the Amazon States Language to accomplish what you desire.

Recently in August 2020, Amazon States Language introduced built-in functions such as string format into it's language spec. https://states-language.net/#appendix-b

Unfortunately, the python SDK is not up to date and does not support the new changes.

As a work around, maybe manually modify the definition before calling workflow create?