garmin_api_activity

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

Annotations already cover the safety profile (readOnly, non-destructive, open-world), and the description usefully adds that raw JSON fields are not normalized. However, the sentence about date ranges defaulting to 7 days and maxing at 31 days is irrelevant and potentially misleading for a tool whose only parameter is an activity_id, adding noise rather than behavioral clarity.

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?

It is short and front-loads the key differentiator (full details beyond the summary), which is good. But the third sentence about date ranges and pagination does not apply to this tool's schema and consumes roughly a third of the text with misleading content.

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 annotations carry the safety profile. Still, the description omits how the required activity_id is sourced and includes a date-range constraint that contradicts the single-parameter schema, leaving an agent with an incomplete and partly confusing picture.

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 description coverage is 0% for the single required parameter, and the description never mentions activity_id at all — not its type, format, or where to obtain it (e.g., from activity search or a summary listing). With no schema text to lean on, the description should have compensated and does not.

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 says this returns full activity details, explicitly noting extra fields beyond the summary tool. The resource (an activity) is clear and it is distinguishable from the summary sibling, though the retrieval verb and differentiation from garmin_api_activity_search are only implied rather than stated.

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?

'Including fields omitted from the summary tool' implies you reach for this when the summary is insufficient, and the parenthetical points at activity search as the paginated alternative. But there is no explicit when/when-not guidance and no mention of the sibling garmin_activity/garmin_activities duplicates.

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