get_cycling_ftp

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

The annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false. The description restates 'read-only' and adds the data source (Garmin Connect), which is modest added context, but discloses nothing about scope, whether historical values are returned, or what an empty result means.

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 short sentences, front-loaded with the purpose. The only wasted material is the date-format parenthetical, which does not apply to a parameterless tool.

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?

Because an output schema exists and the tool has no parameters or annotations gap, the definition is nearly sufficient. Still, for a fitness-metric lookup it does not say whose data is returned (implicitly the authenticated user) or whether the value can be missing, which an agent needs to interpret an empty response.

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?

This tool has zero parameters, which would normally justify a baseline of 4, but the description spends a sentence on 'Dates are YYYY-MM-DD' even though no date parameter exists. That boilerplate is irrelevant here and costs it a point.

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 names a specific verb and resource: 'Return cycling Functional Threshold Power (FTP) information.' Cycling FTP is distinguishable from the nearest sibling concepts (get_lactate_threshold, get_max_metrics, get_training_status), though the description never explicitly contrasts itself with them.

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?

There is no guidance on when to use this tool versus alternatives such as get_lactate_threshold or get_max_metrics, nor any prerequisites or context about when FTP data is meaningful (for example, whether the user must have a power meter). Usage must be inferred from the name alone.

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