garmin_spo2

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

No annotations are provided, so the description carries the full burden. It does disclose useful behavior beyond the schema: the clinical thresholds applied (95% average, 80% nocturnal low) and that it merges daily_summary and a dedicated spo2 table. It does not state auth/permission needs or whether the threshold flagging alters the returned data versus adding 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?

Three short sentences, front-loaded with the primary purpose, with threshold detail following. No filler, though the final sentence about data sources is somewhat redundant given an output schema exists.

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 values need not be explained, and the description covers what the tool analyzes. However, the lone days parameter is left unexplained, which is a real gap for an agent deciding how to invoke it.

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?

There is one parameter (days, default 14) and schema description coverage is 0%, so the description should compensate but instead never mentions the parameter or its time-window meaning. Because there is one undocumented parameter rather than zero, this falls below the 3 baseline.

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 a specific resource (Blood oxygen / SpO2) and a specific analytical behavior (clinical threshold analysis), so an agent knows exactly what this returns. It does not name sibling tools to route away from, but the purpose is unmistakable against the many garmin_* health tools.

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 implied by the topic (retrieve SpO2 data with concern flagging), but there is no explicit when-to-use or when-not guidance relative to alternatives like garmin_health_summary or garmin_health_snapshot. Nothing tells the agent which tool to prefer for oxygen data versus a general health pull.

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