health_daily

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

Annotations already declare readOnlyHint=true. The description adds meaningful behavioral context beyond that by explaining that days use civil-day rollups and align to the local calendar rather than UTC, and that the date range is inclusive. This helps the agent understand timezone behavior without contradicting the 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?

Two short sentences with no filler. The core purpose is front-loaded, and the second sentence adds a distinct behavioral detail. Every sentence earns its place.

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 adequate for a read-only aggregate query, and an output schema exists so return value details are not required. However, given the many sibling tools and the undocumented data_type parameter, a slightly richer description would be needed for fully confident 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 0%, so the description must carry the parameter semantics. It explains start and end as a YYYY-MM-DD inclusive range, which is useful, but it leaves data_type entirely undocumented and gives no examples or valid values. This is only partial compensation for the schema gap.

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 identifies the tool as producing a daily aggregate for one data type over a date range. It is specific about the resource and scope, though it does not explicitly differentiate itself from siblings like health_daily_brief or health_trend.

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 when to use the tool: when a daily aggregate for a single data type over a date range is needed. However, it provides no explicit guidance about when not to use it or which sibling tool would be a better alternative.

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