Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries full burden for behavioral disclosure. While '設定します' implies a write/mutation operation, the description doesn't clarify whether this overwrites existing formatting, requires file write permissions, has side effects on other cells, or provides any confirmation/error response. For a mutation tool with complex nested parameters, this leaves significant behavioral gaps.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.