garmin_daily_summary

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

Annotations already declare readOnly, idempotent and non-destructive, so safety is covered. The description adds a genuinely useful behavioral caveat: results are limited to what Garmin has actually synced for that day, telling the agent that missing metrics mean unsynced, not absent — a real interpretation aid beyond structured fields.

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, front-loaded with the resource and its contents, then the scoping caveat. Minimal waste, though 'and more' is vague filler that costs a little precision.

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?

An output schema exists, so return shape needn't be explained, and the description covers scope plus the day/sync constraint. What remains unaddressed is sibling differentiation, but for a simple one-param read tool this is otherwise complete.

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 coverage is 0% and only 'day' exists with format=date, so the description must carry the semantics. It does: 'explicit local calendar day' clarifies that the value is a local (not UTC) calendar date that must be provided, which is more than the bare date format conveys.

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?

Names a specific verb (read) and resource (daily health summary) and enumerates the metrics returned (steps, calories, resting HR, stress, Body Battery), so the agent knows what it gets back. It does not differentiate against the very similar siblings garmin_daily_metrics and garmin_health_snapshot, which is the main gap at this level.

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?

'Includes only measurements Garmin has synced for the explicit local calendar day' implies the preconditions (data must be synced; day is a local calendar date) but never states when to prefer this over garmin_daily_metrics, garmin_health_snapshot, or the per-metric tools like garmin_sleep and garmin_body_battery.

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