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

Annotations already establish that this is a safe, idempotent read. The description adds meaningful behavioral context beyond annotations: missing values should not be interpreted as zero, and responses must be checked for serviceAnnouncements and surfaced distinctly to the user.

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 short and front-loads the core purpose. The missing-value warning and serviceAnnouncements instruction are useful, though the service-announcement sentence is slightly operationally verbose.

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 low-complexity, single-parameter read tool with rich annotations, the description covers the core operation and two important caveats. It does not fully describe return fields, but no output schema exists and the essential usage context is present.

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 only one parameter, and the schema fully documents activityId with its source tools. The description adds no additional meaning about that parameter, so the baseline of 3 for full schema coverage is appropriate.

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 uses a specific verb, “Read,” and names the exact resource, “effort and feeling for an activity.” It is clear enough to distinguish this from general activity retrieval, though it does not explicitly name sibling tools such as garmin_get_activity_details or garmin_get_activity_laps.

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 object being read. The description gives no explicit when-to-use guidance, no when-not-to-use guidance, and no alternatives such as other activity endpoint tools.

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