Google Health Daily Summary

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

Beyond the annotations that already declare read-only/idempotent/non-destructive, the description adds three non-obvious traits: beta status, non-medical scope, and the availability-based source selection ('when available'). These provide useful context about maturity and data reliance that annotations don't cover.

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 entire description is a single 16-word sentence that front-loads the action and resource, followed by a compact list of caveats. No redundant or filler content.

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?

For a tool with three optional parameters, an output schema, and strong annotations, the description covers the core purpose, data source, and key limitations in one sentence. It omits fallback behavior details and usage comparison to siblings, but overall it provides sufficient context for typical invocations.

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 tool description mentions none of the three parameters, and the schema only provides coverage for timezone (33%). The date and response_format parameters lack descriptive context, leaving the agent to infer semantics from defaults and enum values. This is a significant gap given the low schema coverage.

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 uses the specific verb 'Build' with a clear resource 'daily summary' and identifies its source data ('Google Health rollups and reconciled streams'), differentiating it from sibling tools like daily_rollup or weekly_summary. It also includes the qualifier 'when available' to set scope.

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 implies this is for generating a daily summary but does not explicitly state when to prefer it over google_health_daily_rollup or weekly_summary, nor does it mention any exclusions or fallback guidance. The 'when available' hint suggests conditional availability but lacks concrete alternative guidance.

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