compare_activitiesCompare 2-5 Garmin activities side-by-side to analyze distance, duration, speed, heart rate, calories, elevation, steps, and training effect.
Compare 2-5 activities side by side: distance, duration, speed, heart rate, calories, elevation, steps and training effect.
| Name | Required | Description | Default |
|---|---|---|---|
| activityIds | Yes | Array of 2-5 activity IDs to compare (required) |
Changes observed during successful MCP inspections.
v4.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare the tool read-only, so the safety profile is covered. The description adds useful context about the comparison (side-by-side fields), but it does not disclose return format, error behavior, or any limits beyond the schema-provided range.
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 a single front-loaded sentence that states the action, the count range, and the compared metrics with no filler or repetition. Every phrase earns its place.
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 simple, read-only comparison tool with one well-documented parameter, the description is largely sufficient. It lacks an explicit output/return description, but 'side by side' plus the listed metrics makes the result reasonably predictable.
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 100%: activityIds is already described as an array of 2-5 activity IDs. The description reinforces the range but adds no new semantic information about parameter format or ID source beyond the schema.
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?
Description uses a specific verb ('Compare') with a clear resource ('2-5 activities') and enumerates the metrics involved. This distinguishes it from single-activity tools like get_activity_details and similarity tools like find_similar_activities.
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 clearly implies usage: compare a set of 2-5 activities. However, it does not explicitly state when to prefer this over alternatives such as get_activity_details or analyze_training_period, nor does it mention exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.