icu_get_fitness_summary

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

Annotations already declare read-only, idempotent, non-destructive and open-world behavior, so the safety profile is covered. The description adds value beyond that by noting the response includes interpretation and training recommendations (not just raw numbers) and by clarifying the default scoping to the authenticated athlete with a coach override path.

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?

Three short sentences, each earning its place: metrics first, then trigger conditions, then scoping. The most load-bearing information is front-loaded and there is no filler.

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?

An output schema exists, so return values need not be explained, and the description covers purpose, when to use it, and the athlete-scoping rule. Nothing required to invoke the tool correctly is missing.

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%, so baseline is 3, but the description adds real meaning the schema's 'default: null' does not: that omitting athlete_id resolves to the authenticated athlete, and that passing it is specifically for coaches reading a managed athlete. This clarifies null-vs-value semantics beyond the schema text.

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 uses a specific verb ('Get') and resource ('athlete's fitness/fatigue/form snapshot') and enumerates the exact metrics returned (CTL, ATL, TSB, ramp rate), so an agent knows precisely what comes back. It does not explicitly differentiate from the closest sibling icu_get_fitness_chart, though the word 'snapshot' versus 'chart' implies a current-state vs time-series distinction.

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 gives concrete triggering questions ('how's my form?', 'am I overtrained?') and a category of use ('training-status checks'), which is clear context. It offers no explicit exclusions or named alternatives (e.g. get_fitness_chart for trends), so routing is left partly to inference.

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