Google Health Physical-Time Rollup

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already indicate read-only, non-destructive, idempotent behavior. The description adds no new behavioral context beyond the basic aggregation function, which is already implied. There is no contradiction with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, concise sentence that conveys the core functionality without redundancy. It is front-loaded and efficient, though could benefit from a secondary sentence for disambiguation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Despite having 9 parameters and an output schema, the description fails to explain what 'physical time intervals' means, how rollup granularity (window_size) works, or how pagination and privacy modes affect results. The tool is moderately complex, and the description leaves significant gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description does not mention any parameters, even though schema coverage is only 56%. Key parameters like window_size, data_source_family, and privacy_mode are left to the schema alone, which provides some but incomplete context.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool aggregates a data type over physical time intervals, which distinguishes it from sibling tools like daily_rollup or weekly_summary. However, it does not explicitly contrast with these alternatives or define 'physical time intervals' precisely.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives such as google_health_daily_rollup or google_health_daily_summary. The description lacks any contextual advice on prerequisites or conditions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.