Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries full burden. It mentions optional truncation but omits details: how truncation occurs (by character count?), what happens if source exceeds maxLength, return format, encoding, or error scenarios (e.g., browser not started). Partial but incomplete disclosure.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.