compare_activity_history

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

Annotations already mark this as read-only and non-destructive. The description adds useful behavioral context: it is a comparison across up to eight activities, uses normalized metrics and aerobic decoupling, and applies exact sport type filtering. This is meaningful beyond the annotations, though it does not describe output shape or selection criteria for 'similar'.

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 plus a concise filtering sentence. Every phrase contributes meaning, and there is no repetition of schema or annotation 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?

Given the moderate complexity (5 parameters, 3 required, no output schema), the description covers the tool's purpose, filtering behavior, and activity cap. The main remaining gap is the lack of detail on what the comparison output contains or how 'similar' activities are determined, but this is not severe for a focused comparison tool.

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%, so the description must compensate, and it does: 'over a date range' maps to startDate/endDate, 'exact COROS sport type' to sportType, 'optional name text' to nameContains, and 'up to eight' to maxActivities. It adds semantic meaning to all parameters, though it omits formats or value constraints that the schema leaves unspecified.

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 states a specific verb ('Compare'), a clear resource ('completed COROS activities'), a scope ('up to eight', 'over a date range'), and the method ('normalized summary metrics and aerobic decoupling'). This distinguishes it from sibling tools like analyze_aerobic_decoupling (single activity analysis) and list_activities (listing without comparison).

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 implies the use case: compare multiple completed COROS activities in a date range, filtered by sport type and name. However, it does not explicitly state when to prefer this over alternatives or mention any exclusions, leaving the agent to infer routing from sibling names.

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