Retrieve time spent in each power zone for a specific Garmin activity by supplying its activity ID.
Time spent in each power zone during an activity.
| Name | Required | Description | Default |
|---|---|---|---|
| activityId | Yes | Numeric id |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds only the notion that output is per-zone time, which is a modest restatement of the tool name; no auth needs, scope limits, or behavior on activities without power data are disclosed.
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 short sentence with no filler and the key concept (time in each power zone) front-loaded. It is efficient, though the odd 'in_timezones' naming is not unpacked anywhere.
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?
There is no output schema, and the description gives only the conceptual shape of the return value. It never clarifies the confusing 'timezones' element of the name (it means power-zone buckets, not time zones), which is the main thing an agent would misread.
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 100% and there is exactly one parameter (activityId), so the schema carries the burden. The description adds nothing about the identifier's form (numeric id vs string), leaving parameter semantics entirely to the schema — baseline 3.
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: time spent in each power zone during a single activity. It is distinguishable from the near-named sibling get_activity_hr_in_timezones by the word 'power', though it never explicitly contrasts itself with tools like get_power_zones or get_power_zones_for_sport.
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 no when-to-use guidance, no prerequisites, and no alternatives. An agent cannot tell from this text whether it should call get_power_zones (zone definitions) or this tool (time attribution), nor that an activityId is mandatory.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.