Found 2026-09-10.
The most basic question a compare can answer is "does adding this skill change anything," which wants "baselineSkills": []. Config load rejects that with compare requires at least one baseline skill. The workaround is a placeholder skill whose body says "No additional guidance," which contaminates the baseline slightly in inline delivery (the text is in the system prompt) and more in install delivery (a registered skill with a description the model can see).
Suggest allowing an empty baseline skill list. In inline delivery the baseline system prompt is then the agent alone; in install delivery the sandbox registry is empty for that arm.
Found 2026-09-10.
The most basic question a compare can answer is "does adding this skill change anything," which wants
"baselineSkills": []. Config load rejects that withcompare requires at least one baseline skill. The workaround is a placeholder skill whose body says "No additional guidance," which contaminates the baseline slightly in inline delivery (the text is in the system prompt) and more in install delivery (a registered skill with a description the model can see).Suggest allowing an empty baseline skill list. In inline delivery the baseline system prompt is then the agent alone; in install delivery the sandbox registry is empty for that arm.