get_activity_power_in_timezones

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

With no annotations, the description carries full burden. It discloses output details (time spent, watt thresholds, duration) and prerequisites (power meter, FTP). It does not state side effects, but the read-only nature is implicit from the name and description, and there is no contradiction.

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 concise and well-structured: a one-sentence summary, output details, prerequisites, and parameter explanation. No redundant or vague wording.

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?

Provides essential context: what it returns, prerequisites, and parameter meaning. It does not mention error cases or what happens when no power data exists, but these are minor gaps given the tool's simplicity and the presence of related siblings with similar patterns.

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?

The single parameter activity_id is clearly explained in the Args section as 'ID of the activity to retrieve power zone data for'. Although the schema lacks description, the description fully compensates, making the parameter's meaning unambiguous.

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 states a specific action ('Get power distribution across training zones') for a specific resource ('an activity'). This distinguishes it from sibling tools like get_activity_hr_in_timezones or get_activity_splits.

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?

Provides condition 'Requires a power meter' and explains FTP basis, which tells the agent when this tool is appropriate. It does not explicitly mention when to choose an alternative, but the unique purpose is clear enough.

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