Google Health Daily Rollup

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds that it uses 'dailyRollUp' and operates over civil days, but it doesn't disclose pagination behavior, rate limits, or output nuances. This is adequate given the annotation coverage, but not rich.

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?

Two sentences, with the first stating the core function and the second listing example use cases. No redundant information or fluff. It is front-loaded with the action and resource.

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?

The description is brief for a tool with 10 parameters and many sibling tools. It doesn't explain how to determine valid data types (though schema points to list_data_types), the relationship to rollup/daily_summary, or pagination details. The output schema exists, so return values are handled, but the description lacks enough context for correct tool selection and invocation.

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?

Schema description coverage is 50%, with parameters like data_type and page_size having detailed schema descriptions. The tool description itself only references data types generically and doesn't explain parameters like start_date, window_size_days, or response_format. It adds marginal value beyond the schema and doesn't fully compensate for the undocumented parameters.

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 action ('Aggregate a data type') and the resource ('over civil days using Google Health dailyRollUp'), naming the underlying API method. It also lists example use cases ('steps, distance, calories...'), which helps distinguish it from sibling aggregation tools like weekly_summary.

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?

The description provides context (useful for steps/distance/etc.) but does not explicitly say when to use this tool over siblings like google_health_rollup or google_health_daily_summary. No when-not-to-use or alternative guidance is given, leaving the choice ambiguous for an agent.

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