Garmin SpO2

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

Annotations already indicate readOnly, idempotent, and non-destructive behavior, so the description's disclaimer 'Not medical advice' adds minimal behavioral context. It hints that data may not be available ('when available'), but provides no detail on missing data handling or 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 extremely concise at two sentences with no unnecessary words. It immediately states the action and resource, and the disclaimer is appropriately placed. 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?

Despite having an output schema and three parameters, the description is minimal. It does not explain what the returned data includes (e.g., average, min, max), how to interpret 'when available', or how privacy_mode alters the output. The completeness is inadequate for a tool that is part of a large family of similar getters.

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 67% (two of three parameters have descriptions). The tool description only emphasizes the 'date' parameter by saying 'for a date,' but does not explain privacy_mode or response_format. These are defined in the schema but the description adds no extra meaning to compensate for the uncovered parameter.

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 tool retrieves Garmin Pulse Ox/SpO2 data for a specific date, using a specific verb and resource. However, it does not distinguish this tool from sibling tools like garmin_get_heart_day or garmin_get_body_battery_day, as they all follow a similar pattern.

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?

No guidance is provided on when to use this tool versus alternatives. The description does not mention prerequisites, exclusions, or context where other tools might be preferred, leaving the agent without decision support.

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