get_daily_stats

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

With no annotations provided, the description carries the full burden of disclosing behavior. It clearly indicates a read operation returning a summary of daily metrics, which is helpful, but it does not explain how missing data, invalid dates, or timezone effects are handled, and it does not define the response structure.

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 compact and front-loaded: one sentence defines the purpose and the Args section documents the only parameter. Every sentence adds useful information without redundancy or filler.

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 single-optional-parameter read tool, the description is adequate but has clear gaps: there is no output schema, no indication of return shape, and no mention of edge cases like dates with no recorded data. The 'etc.' leaves the metric list slightly open-ended, and 'today' is not timezone-qualified.

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 schema only exposes a nullable string parameter with a null default, providing no semantic meaning. The description compensates fully by specifying the exact date format (YYYY-MM-DD) and the effective default behavior ('Defaults to today'), which is essential for correct invocation.

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 verb ('Get') and resource ('a day's overall stats summary') and enumerates the included metrics, making the tool's function obvious. It is not a tautology and is easily distinguishable from sibling per-metric tools like get_heart_rate or get_sleep, though it does not explicitly name an alternative.

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?

There is no explicit guidance about when to use this tool versus alternatives such as get_activity, get_resting_heart_rate, or list_activities. The phrase 'overall stats summary' implies aggregate daily usage, but the description does not state when not to use it or prefer a sibling.

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