get_spo2_acclimation

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

Annotations already cover read-only and open-world semantics, and the description adds genuinely non-obvious behavior: a day with no data still returns the object with null fields (illustrated with 2030-01-01), which prevents the agent from misreading an empty response as an error. It also identifies the backing endpoint and DTO type for traceability. It stops short of describing pagination or field-level error behavior, so not a 5.

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?

Front-loaded with purpose, then supporting detail; every sentence carries information. The endpoint path and DTO name are somewhat implementation-flavored but are defensible for an agent that must map to Garmin's spec.

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-parameter read tool with no output schema, the description adequately covers the return payload by naming its constituent parts and the null-on-no-data case. Only minor gaps remain, such as whether partial data can occur or how units/typing are represented.

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 already 100% with a formatted date description, so the schema does the heavy lifting. The description still adds value by showing cdate as a path placeholder and demonstrating a concrete example value, reinforcing that this is a single-day lookup rather than a range query.

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 resource and scope: one day's SpO2 readings with altitude acclimation, then enumerates what the payload contains (averages, sleep and hourly series, monitoring environment). It explicitly names the nearest sibling, getSpo2Data, so an agent can tell the two apart without opening either schema.

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?

The description gives content-level context (acclimation, hourly series, environment) that lets an agent infer when this is the right call, and it flags that empty days still return an object. However, the sibling differentiation is phrased as an API path difference ("Distinct from getSpo2Data's path") rather than an explicit use-this-when/use-that-when rule, so selection still requires inference.

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