garmin_profile

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the safety profile is covered. The description adds an inventory of returned data points, which is mild behavioral value, but says nothing about data freshness, whether the profile is static or user-editable, or any auth/login requirement implied by openWorldHint. Modest added value beyond the 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?

A single front-loaded sentence with the framing purpose stated first and the content inventory after the colon. Every clause carries content; the only nit is that the enumerated list is dense and slightly overlaps a sibling's territory.

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 an output schema present, the description need not explain return values, and annotations cover the read-only/idempotent nature of this zero-param call. Enough is said for an agent to call it correctly; only freshness/currency of the profile data is left unstated, which is a minor gap.

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?

The tool takes zero parameters, so the baseline is 4 and there is nothing for the description to compensate for. It correctly implies no filtering or arguments are needed to retrieve the profile.

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 resource and its contents: user context for interpreting other data (time zone/units, HR zones per sport, Fitness Age, latest weight). An agent can tell this is the profile/reference-data tool rather than an activity or measurement tool. It falls short of 5 because it is a noun phrase without a verb and does not explicitly distinguish itself from the sibling garmin_weight, which overlaps with the 'latest weight' item it lists.

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 phrase 'user context for interpreting other data' implies the use case: fetch this to ground unit conversions, time zone normalization, or zone-based interpretation of other readings. However, there is no explicit when-to-use instruction, no when-not guidance, and no sibling named as an alternative, so the routing signal is only implied.

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