garmin_fitness

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

Annotations already mark readOnlyHint=true and destructiveHint=false, so the safety profile is known. The description adds analytical scope and dependency on a stored goal ('against the stored goal', 'projected to race day') but offers no behavioral details such as data source freshness or error conditions.

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?

Text is two sentences plus an introductory clause; front-loaded with 'Is training working', then lists outputs and use cases. Some redundancy exists: race projection/race planning and taper guidance/taper timing are repeated in the second sentence.

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?

With read-only annotation, an output schema, and a 2-parameter schema that fully documents inputs, the description provides enough context for a typical agent. It covers primary use cases and related tool, though it omits edge-case behavior when no goal is stored.

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?

Input schema covers both parameters (weeks, anchor_date) with descriptions and defaults, so description need not repeat them. Description does not mention these parameters at all, but schema coverage is 100%, so baseline 3 applies.

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 opens with 'Is training working:' and enumerates specific outputs (VO2max, efficiency trends, HR at fixed pace, long-run durability, race projection, form/taper). It distinguishes from siblings by naming a related tool for setting goals and specifying call intents like 'am I getting fitter'.

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?

'Call for 'am I getting fitter', race planning, taper timing, goal feasibility' provides explicit when-to-use guidance, and points to garmin_set_profile for goal configuration. However, it does not explicitly list exclusions or alternative analytical tools.

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