Pulse Ox (one day)

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

Annotations already declare read-only, idempotent, non-destructive, open-world behavior, so safety is covered. The description adds real context beyond that by disclosing the shape of the payload and what detail='full' unlocks (every reading plus altitude data), which matters since there is no output schema.

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 compact sentences, zero filler, with the metric and scope front-loaded and the detail-mode caveat immediately after.

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?

With no output schema, the description carries the burden of describing return values and does so thoroughly, including detail mode. Only minor gaps remain, such as units and how the 7-day average behaves for a single-day request.

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 100%, so both parameters are already documented, giving a baseline of 3. The description does add meaning for detail='full' beyond the schema's terse 'Garmin's raw payload', but says nothing extra about the date parameter's accepted formats or time-zone resolution.

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?

States a specific metric and scope ('SpO2 for one day') and enumerates the exact aggregates returned (average, lowest, sleep average, 7-day average, hourly averages). An agent can tell what it retrieves, though it never contrasts itself with overlapping siblings like get_sleep or get_daily_summaries.

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?

Usage is only implied by the metric name and the 'one day' scope; there is no explicit when-to-use versus alternatives such as get_sleep_summaries or get_daily_summaries, and no stated preconditions or date-range limits.

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