strategy_spec_legacy
What happened
Every Strategy Spec names the FORGE_API level it was written for. One with no forge_api was made by the earlier Studio and is refused with 400.
What to do
Open the strategy in the Studio, which updates it, and save it again.
Example
json
{
"error": "This strategy is in the older Studio format. Open it in the Studio to update it.",
"code": "strategy_spec_legacy",
"path": "forge_api"
}