get_activity_zones

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

No annotations are provided, so the description carries full burden for behavioral traits. It does not disclose any side effects, permissions, rate limits, or data availability constraints. For a read-only tool, it should at least indicate it's a safe query.

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?

Two sentences, each carrying essential information. The purpose is front-loaded, and no redundant or extraneous content exists.

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 one-parameter input and no output schema, the description adequately explains the return values (zone boundaries, time, percentage) and the use case (activity-specific zone analysis). Minor omission: no mention that zones may not exist for all activities.

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% with a clear description of activity_id. The description reinforces that the parameter identifies the activity but adds no new semantic details beyond what the schema already provides.

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 clearly specifies the tool's action (get zone distribution), the resource (activity), and the types (heart rate, pace, power). It also lists the return values (zone boundaries, time in seconds, percentage). This distinguishes it from siblings like get_athlete_zones.

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 only states what the tool does, with no guidance on when to use it versus alternatives, when not to use it, or prerequisites. Sibling tools like get_athlete_zones might be related but are not mentioned.

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